Is Red Wine Really the Cause of That Headache?

Is Red Wine Really the Cause of That Headache?

I KNOW PLENTY of people who suffer from headaches that they believe are triggered by drinking red wine—including, occasionally, me. Red Wine Headache is such a common complaint that it has both an acronym (RWH) and its very own Wikipedia page, albeit with a disclaimer noting a lack of medical evidence regarding the condition and its causes. As Dr. Alexander Mauskop, director and founder of the New York Headache Center in Manhattan, said, “We don’t know anything for sure.”

Wine-related headaches are one of the center’s most common complaints, especially among migraine sufferers, said Dr. Mauskop. He has heard many theories as to the cause. One posits that the type of oak used in the fermentation and aging of wine triggers headaches, though Dr. Mauskop couldn’t recall if French oak or American oak was said to be worse. He’s also heard theories about the sulfites in red wine as contributing factors, but he sees very few headache patients who are truly sulfite-allergic. That condition is actually quite rare, and besides, red wines have a lower concentration of sulfites overall than white wines do.

Dehydration can cause headaches, and alcohol acts as a diuretic—which means, of course, that dehydration can result from drinking both red and white wines, as well as other alcoholic beverages. A red wine headache might also signal an insufficiency of magnesium. “Alcohol is a major depleter of magnesium,” said Dr. Mauskop. He recommends that headache sufferers take 400 milligrams of magnesium per day.

Dr. Mauskop himself gets headaches from red wine occasionally. When he feels a headache coming on, he’ll sometimes take Imitrex (generic name: Sumatriptan), a drug that affects serotonin receptors, thereby relieving pain.

Oddly enough, though there is much discussion of red wine headaches, just as the Wikipedia page warned, I found very little medical research on the topic. After consulting with experts, the only study I unearthed was published three decades ago in the Lancet, the influential British medical journal.

In the 1988 study, “Red Wine as a Cause of Migraine,” six researchers served 19 members of a patient group at the Princess Margaret Migraine Clinic in London either vodka or red wine to assess whether their headaches were red wine-specific or caused strictly by alcohol. The drinks were served in dark vessels and other efforts were made to disguise their flavor as well as their color.

Some of the participants were migraine sufferers who identified themselves as red wine-sensitive, others were migraine patients who were not, as far as they knew, red wine-sensitive, and another eight participants were a control group of non-migraine sufferers. The red wine was described in the study as “Spanish” and the vodka was blended with lemon juice to dilute it to a similar alcohol level. Study participants were given 300 milliliters, equal to about 10 ounces or two typical glasses of wine.

The results were inconclusive: Some participants who claimed to be red wine-sensitive developed headaches from red wine, some did not. Some who claimed no such sensitivity did develop headaches after drinking vodka. The researchers suggested various possible explanations. Was it simply a matter of drinking too much? The study acknowledged that tyramine, another naturally occurring compound in food and wine, has been found to trigger migraines. But in this case, the tyramine level in the wine administered to participants was noted as quite low: just 2 milligrams per liter, which means each patient consumed less than 1 milligram. The conclusion: More research was needed.

‘The doctor has heard theories about sulfites in red wine, but he sees very few headache patients who are truly sulfite-allergic.’

I was curious about the potential of tyramine to trigger headaches but had little luck finding any further information on the topic. Chris Gerling, an extension associate at Cornell University’s Viticulture and Enology program in Ithaca, N.Y., noted that tyramine levels in grapes are highly variable. “It’s really hard to make a blanket statement about colors or grape varieties. Regions of the world report different findings,” he said. Mr. Gerling did note that since red wines tend to undergo malolactic fermentation more often than white wines do and often spend time in barrels where bacteria can thrive, reds have the potential to develop higher levels of tyramine.

Red wines also have higher levels of histamines, a byproduct of fermentation, than white wines. Some have cited histamines as a possible cause for headaches, though Mr. Gerling cautioned, in what was becoming a familiar refrain, “Nothing can be stated with certainty.” Phenols, compounds that give red wines some of their color, flavor and body, have also been put forward as possible headache-causing culprits—as yet another unproven theory.

So I found myself pretty much right back where I began, with lots of theories and no real answer. It wasn’t possible to identify potentially problematic wines by the high tyramine or phenol levels of the grapes or the amount of time they spent in particular barrels or even their respective histamine levels. I could stock up on magnesium and take a tablet a day, and I could drink water along with wine. I could also follow the lead of some friends who identify as red wine-sensitive and take an antihistamine tablet when I indulge.

These strategies might or might not work, Dr. Mauskop said. If I already had enough magnesium in my system, taking more wouldn’t prevent a headache. I could take a blood test to determine my magnesium level and, depending on the results, visit his office for a magnesium shot. Some of his patients do so monthly and find it helpful. But Dr. Mauskop didn’t think the antihistamine would be of much help. “Histamine release by red wine is not the main reason for headaches, otherwise antihistamines would help most people—and they don’t,” he said.

I’m not going to stop drinking red wine, even if it gives me a headache from time to time. And there is a chance that sometime in the future I might be better able to predict which wines will be more likely to make my head hurt. Dr. Morris Levin, chief of the headache medicine division and the director of the University of California San Francisco Headache Center, is working on a research project that he thinks might identify potentially problematic reds. “Wouldn’t it be great to be able to tell people which wines would be safe to drink?” he asked, rhetorically.

Dr. Levin is about to begin the process of recruiting patients, and he hopes to include 50 participants or more in the research study. Shamelessly, I petitioned him to include me. “I’m putting you on the list,” he said. While I wait to hear more, it’s given me something to feel hopeful about in the new year.


This article was originally published in The Wall Street Journal. Read the original article.

Is Eating Deli Meats Really That Bad for You?

Is Eating Deli Meats Really That Bad for You?

Q. Is eating deli meats really that bad? Does it make a difference if it’s organic, nitrate-free or uncured?

A. Meat and poultry are excellent sources of protein, B vitamins and certain minerals, but consuming even small amounts of processed meat increases the risk of colorectal cancer.

“We see a 4 percent increase in the risk of cancer even at 15 grams a day, which is a single slice of ham on a sandwich,” said Dr. Nigel Brockton, director of research for the American Institute for Cancer Research. Eating a more typical serving of 50 grams of processed meat a day would increase the risk of colorectal cancer by 18 percent, a 2011 review of studies found.

Unprocessed red meat, by comparison, increases cancer risk only at amounts greater than 100 grams a day, and the evidence for that link is limited, Dr. Brockton said, adding that the institute advises people to “limit” red meat but “avoid” processed meat.

There is some evidence suggesting an association between processed meat and stomach cancer. And a recent study found an increased risk of breast cancer among women who ate the most processed meats.

Processed meat refers to any meat, including pork, poultry, lamb, goat or others, that has been salted, smoked, cured, fermented or otherwise processed for preservation or to enhance the flavor. The category includes hot dogs, ham, bacon and turkey bacon, corned beef, pepperoni, salami, smoked turkey, bologna and other luncheon and deli meats, sausages, corned beef, biltong or beef jerky, canned meat and meat-based preparations and sauces, among others.

Many of these meats tend to be high in salt and saturated fat, though lean and low-sodium options are available.

Processed meats are often cured by adding sodium nitrite, which gives them a pink color and a distinct taste, or by adding sodium nitrite and lactic acid, which provides a tangy taste, according to The American Meat Institute. In the past, nitrates, in the form of saltpeter, were traditionally used. Nitrates or nitrites inhibit the growth of botulism and scientists suspect they may be involved in the formation of cancer-causing compounds in the body. (Vegetables also contain nitrates and nitrites, but eating them is not associated with an increased risk of cancer.)

Some products that claim to be “natural” or “organic” may say they are processed without nitrites or nitrates, and the label may say the item has “no artificial preservatives” or is “uncured.” But nutritionists warn that food manufacturers may still add vegetable powders or juices such as celery juice or beetroot juice that contain naturally occurring nitrates, which are converted to nitrites either in the food itself or when they interact with bacteria in our bodies.

The food label will state that there are “no nitrates or nitrites added,” but an asterisk will often lead to a fine-print addendum with the clarification, “except those naturally occurring in celery juice powder,” sea salt or a vegetable juice.

As a result some “natural” or “organic” roast beef and turkey breast, or other products cured with sea salt, evaporated cane juice, potato starch, or natural flavorings or seasonings, may end up with just as high a nitrite content as meats with sodium nitrite added.

Adding to the confusion for consumers is that the U.S.D.A. requires these meats be labeled “uncured” because they are produced without added nitrites or nitrates.

“The average person goes to the store and sees claims like ‘organic, ‘natural,’ or ‘no added nitrates or nitrites,’ and they assume those meats are safer, and they’re not,” said Bonnie Liebman, director of nutrition at the Center for Science in the Public Interest, a food safety advocacy group.

The bottom line: If you’re trying to avoid processed meats in order to reduce your risk of cancer, it may be hard to know whether products labeled “natural,” “organic,” “uncured,” or “nitrate and nitrite free” fall into this category or not.

The C.S.P.I. has been urging the Department of Agriculture to require labels on processed meats and poultry that identify the products and inform the public that frequent consumption may increase the risk of colon cancer. A spokeswoman for the U.S.D.A.’s Food Safety and Inspection Service, Veronika Pfaeffle, said recently that the petition, filed in Dec. 2016, is still “under review.”

Freezing Your Coffee Beans? The Experts Say You’re Doing It All Wrong

Freezing Your Coffee Beans? The Experts Say You’re Doing It All Wrong

MELBOURNE, Australia—Just before the final round of Australia’s top coffee competition, barista Tilly Sproule stocked up on a crucial ingredient. She bought nearly 20 pounds of dry ice.

She packed the ice into a box, divvied up her coffee beans into small plastic vials and inserted the tubes into the ice. Her goal was to chill her beans to below zero. She wanted them so brittle they would grind more evenly than at room temperature. It was vital, she said, to making an incredible cup of joe.

“Backstage is hilarious,” Ms. Sproule said. “There’s like five or six freezers, I think. Everyone’s on the bandwagon.”

It isn’t just about getting a better grind. Some cafes are freezing their best beans so they’ll last months or even years—far beyond the couple of weeks that roasted beans typically taste their best. Frozen-bean advocates imagine a day when coffee aficionados can behave like wine connoisseurs, poring over long coffee menus to sample numerous vintages.

Scientists say there is little research so far into how best to store frozen beans for the long term. So coffee nerds are trying to figure it out for themselves. Some roasters are trying ultralow-temperature freezers typically used by labs to store biological samples. Others use frozen-food warehouses. Some freeze unroasted beans, others roasted.

“People haven’t done this before,” says Christopher Hendon, an assistant professor of chemistry at the University of Oregon who has studied coffee. “A good analogy for this is: Imagine being the first guy ever to provide aged whiskey. Imagine saying, ‘Hey, 28 years from now, we are going to make some money.’ ”

One thing the coffee experts figured out right away: They had to do better than ordinary consumers who buy a bag of coffee at the grocery store, use some of it and just toss the rest into the freezer.

“Thirty years ago, people said, ‘Oh, freeze all your coffee and it’s better for it,’ ” says Will Young, the owner of Campos Coffee in Sydney. “But then people were doing it badly. They were doing it in open containers, frost forming on the actual bean itself. It was just really embarrassing for coffee.”

Mr. Hendon says coffee beans need to be frozen in an airtight container to keep out excess moisture and prevent unwanted odors from contaminating the beans. More study is needed, he says, to determine how the rate of freezing and humidity affects the beans.

It helps to have a reliable freezer. Mr. Young arrived at his roastery one day last year to find a mini-freezer had stopped working. Inside was unroasted Panamanian coffee that had cost more than $100 a pound. It had been frozen for nine months. It wasn’t anymore.

The unplanned thawing, he says, left the beans tasting no better than a $6-a-pound grade. Still, some of the beans were good enough to use in the regular espresso blend he sells to cafes. That week, he says, cafe customers were “drinking some of the best coffee in the world, just a very small amount of it in each cup.”

Mr. Young upgraded to a freezer that cost about $3,000. He uses it to store ultrapremium coffee from Panama, Yemen and Costa Rica. Preserving it in a freezer just for a year would be a success. Mr. Young says unroasted beans typically start to degrade after six months, even if stored in a climate- and humidity-controlled warehouse.

George Howell, who runs his namesake coffee business in Boston, has about 200,000 pounds of unroasted beans in a warehouse used for frozen food. He also has several ice-cream freezers in his roastery to keep the more expensive beans, including a Guatemalan variety harvested back in 2012.

Still, Mr. Howell says about 10% of his frozen beans still degrade, probably because the beans weren’t properly dried after harvest.

“This has all been trial and error and just following what works,” he says. “We’re not scientists.”

Mike Cracknell, managing director of Vertue Coffee Roasters in Melbourne, tried freezing roasted coffee beans in a sandwich bag in his freezer at home. He says the coffee ended up tasting like rotten fruit. Subsequent experiments with a vacuum seal yielded better results, but he doesn’t think freezing beans will become standard practice for most roasters and cafes.

“It’s over-engineering,” he says. “When the majority of people might be enjoying their large cappuccino or their regular flat white with one sugar, there’s no need to do that.”

Such skepticism isn’t stopping some cafes. Customers at a new Sydney cafe run by ONA Coffee can order from what cafe manager Isaac Kim calls the “reserve menu.” The beans, already roasted, are stored in a freezer in single-serve, vacuum-sealed packs. Some coffee beans peak in flavor about 10 days after roasting and may start to degrade around the two-week mark, Mr. Kim says.

Carol Leong, who stopped by the ONA cafe with friends recently, said it was the first time she saw a barista take beans out of a freezer. “Just then I saw it and I was like, whoa, that’s pretty cool,” she said.

Ms. Sproule, from Tim Adams Specialty Coffee, didn’t win the Australian coffee championships, but she swears by her dry-ice technique. For optimal grinding, she says, she likes to get the beans to at least 58 degrees below zero.

At that temperature, she explains, “you get less fines and less boulders, and more like a shattered, uniform particle size.”

The winner of the contest was Matthew Lewin, who works at ONA. He said he used a portable freezer to chill his beans. At the main roasting facility in Canberra, Australia’s capital, ONA is looking to build a walk-in freezer.

Can You Get Over a Food Intolerance?

Can You Get Over a Food Intolerance?

Q. Can you desensitize yourself to a food intolerance?

A. Food intolerances, which the American Academy of Allergy, Asthma & Immunology defines as “difficulty digesting a particular food,” are different than food allergies and often resolve on their own. Food allergies involve the immune system, whereas food intolerances generally do not.

Some food intolerances are well understood. Tyramine in chocolate and cheeses, for example, can trigger migraine headaches in some people. Similarly, histamine in fish such as mackerel and tuna can cause nausea, vomiting and flushing. Sulfites in dried fruit and tartrazine in food dyes can cause asthma exacerbations.

But the cause of most food intolerances remains unknown.

In a British study of more than 10,000 patients, the foods most often associated with intolerances were chocolate, food additives, citrus fruits, fish, shellfish, milk, cheese, eggs and nuts. The most common symptoms of these intolerances were hay fever, headaches, joint pain, itching, hives and stomach discomfort.

In the largest study to date, doctors studied the electronic health records of 2.7 million patients in Massachusetts. They found that 3.6 percent had at least one food intolerance or food allergy. The list of offending foods was similar to that of the British study.

But a caveat must be noted. In both studies the investigators were unable to discriminate between food intolerances and food allergies. Because the symptoms overlap extensively, one cannot differentiate intolerance from allergy without specialized testing.

Further complicating things, some foods can cause both intolerance and allergy. Cow’s milk is a good example. It can provoke bloating and diarrhea in individuals with lactase deficiency — a food intolerance — and can cause wheezing and hives in those allergic to the beta-lactoglobulin milk protein — a food allergy.

An elimination diet, in which the potentially offending food is removed from the diet, is usually the first step in diagnosing food intolerance. While elimination diets have not been studied systematically, resolution of symptoms upon withdrawal of the food in question strongly suggests a food intolerance.

Reintroducing an offending food is often possible. The British researchers were able to do this with most of the patients in their study without provoking serious reactions. But this should be done under a doctor’s care.

Because of the complexities and potential pitfalls in the diagnosis and treatment of food intolerance, one should seek guidance from a specialist, typically an allergist or a gastroenterologist, depending on the nature of one’s symptoms.

The Trouble With Rice

The Trouble With Rice

For the past few years, Mary Lou Guerinot has been keeping watch over experimental fields in southeast Texas, monitoring rice plants as they suck metals and other troublesome elements from the soil.

If the fields are flooded in the traditional paddy method, she has found, the rice handily takes up arsenic. But if the water is reduced in an effort to limit arsenic, the plant instead absorbs cadmium — also a dangerous element.

“It’s almost either-or, day-and-night as to whether we see arsenic or cadmium in the rice,” said Dr. Guerinot, a molecular geneticist and professor of biology at Dartmouth College.

The levels of arsenic and cadmium at the study site are not high enough to provoke alarm, she emphasized. Still, it is dawning on scientists like her that rice, one of the most widely consumed foods in the world, is also one of nature’s great scavengers of metallic compounds.

Consumers have already become alarmed over reports of rice-borne arsenic in everything from cereal bars to baby food. Some food manufacturers have stepped up screening for arsenic in their products, and agencies such as the Food and Drug Administration now recommend that people eat a variety of grains to “minimize potential adverse health consequences from eating an excess of any one food.”

But it’s not just arsenic and cadmium, which are present in soil both as naturally occurring elements and as industrial byproducts. Recent studies have shown that rice is custom-built to pull a number of metals from the soil, among them mercury and even tungsten. The findings have led to a new push by scientists and growers to make the grain less susceptible to metal contamination.

The highest levels often occur in brown rice, because elements like arsenic accumulate in bran and husk, which are polished off in the processing of white rice. The Department of Agriculture estimates that on average arsenic levels are 10 times as high in rice bran as in polished rice.

Although these are mostly tiny amounts — in the part per billion range — chronic exposure to arsenic, even at very low levels, can affect health. The F.D.A. is now considering whether a safety level should be set for arsenic in rice.

“Rice is a problem because it’s such a widely consumed grain,” said Rufus Chaney, a senior research agronomist with the U.S.D.A.’s Agricultural Research Service, who is leading a investigation of metal uptake by food crops. “But it’s also a fascinating plant.”

Like people, plants have systems for taking up and absorbing necessary nutrients. In plants, these “transporter” systems work to pull minerals such as iron, calcium, zinc and manganese from the soil.

The rice plant has a well-designed system for taking up silicon compounds, or silicate, which help strengthen the plant and give stiffness and shape to its stems. Tissues generally referred to as phloem move such water-soluble nutrients throughout the plant.

But that delivery system also inclines the plant to vacuum up arsenic compounds, which are unfortunately similar in structure to silicate. And the traditional methods of growing rice, which often involve flooding a field, encourage formation of a soluble arsenic compound, arsenite, that is readily transported by the rice plant.

“The issue with the rice plant is that it tends to store the arsenic in the grain, rather than in the leaves or elsewhere,” said Jody Banks, a plant biologist at Purdue University, who studies arsenic uptake in plants. “It moves there quite easily.”

The highest concentrations of arsenic in rice-growing regions are mostly found in parts of Asia — including Bangladesh and India — where the underlying arsenic-rich bedrock contaminates groundwater used for both drinking and irrigation of rice fields.

But arsenic at lower levels is found in all soils, including American fields. The fertile soils fanning out across the Mississippi River floodplain are up to five times as high in arsenic as other parts of Louisiana, Mississippi and Arkansas, according to studies done by the United States Geological Survey.

It’s for that reason, as well as for water conservation, that scientists have experimented with reducing the amount of water used for rice fields. But as Dr. Guerinot has found, that makes cadmium more available to the plant instead.

Other plants also take up cadmium, Dr. Chaney noted, usually by the channels normally used to acquire zinc from the soil. But the rice plant, curiously, absorbs nearly all of its cadmium through a manganese transport system. And this route — discovered by a determined group of Japanese researchers — brings a new set of complications.

While zinc is relatively common in soil, soluble manganese is less readily found. So cadmium has little competition in the rice plant’s transport system — meaning that it is accumulated with apparent enthusiasm.

The association between cadmium in rice and human disease goes back decades. Most scientists cite the identification of itai-itai (ouch-ouch) disease in Japan during the 1960s as the first recognition of this problem. The name comes from the painful effects of bone fractures, one of many health problems related to cadmium exposure.

Researchers eventually discovered that cadmium pollution from mines and other industry had spread into rice farming areas in Japan, causing the grain to be loaded with the toxic metal. A host of similar problems have occurred in China, setting off an uproar over tainted rice last year.

Scientists say that the cadmium occurring naturally in American soil is not high enough to cause acute disease. Still, because rice is such an important food crop, scientists are searching for ways to block its metal-acquiring tendencies.

There are efforts to breed rice plants that transfer more zinc and iron into the grain, which would both increase nutritional quality and reduce toxicity. There are also programs, including the experiment in Texas, that try to breed improved rice cultivars less prone to absorb toxic minerals.

And researchers have explored the idea of genetic engineering to make the plant’s transport systems more precise so that cadmium or arsenic is filtered out.

Finally, they are looking into using other plants to reduce the toxic elements in the soils themselves, a process called phytoextraction. Dr. Banks, for instance, is studying a fern that deftly pulls arsenic from the soil and stores it in the fronds.

The plant, known as a Chinese brake or ladder fern, is so talented in this regard that the Chinese have approached American scientists about the feasibility of using it to clean up contaminated soils. Of course the ferns eventually have to be incinerated or taken to a toxic disposal site.

“You definitely wouldn’t want to eat them,” said Dr. Banks.

Exercise May Help to Fend Off Depression

Exercise May Help to Fend Off Depression

Jogging for 15 minutes a day, or walking or gardening for somewhat longer, could help protect people against developing depression, according to an innovative new study published last month in JAMA Psychiatry. The study involved hundreds of thousands of people and used a type of statistical analysis to establish, for the first time, that physical activity may help prevent depression, a finding with considerable relevance for any of us interested in maintaining or bolstering our mental health.

Plenty of past studies have examined the connections between exercise, moods and psychological well-being, of course. And most have concluded that physically active people tend to be happier and less prone to anxiety and severe depression than people who seldom move much.

But those past studies showed only that exercise and depression are linked, not that exercise actually causes a drop in depression risk. Most were longitudinal or cross-sectional, looking at people’s exercise habits over a certain period or at a single point of time and then determining whether there might be statistical relationships between the two. In other words, active people might be less likely to become depressed than inactive people. But it’s also possible that people who aren’t prone to depression may be more likely to exercise. Those types of studies may be tantalizing, but they can’t prove anything about cause and effect.

To show causation, scientists rely on randomized experiments, during which they assign people to, for instance, exercise or not and then monitor the outcomes. Researchers have been using randomized trials to look at whether exercise can treat depression after people already have developed the condition, and the results have been encouraging.

But it would be almost impossible to mount a randomized trial looking at whether exercise prevents depression, since you would need to recruit a large number of people, convince some to exercise, others not, follow them for years and hope that enough develop depression to make any statistical analysis meaningful. The logistics involved would be daunting, if not impossible, and the costs prohibitive.

Enter Mendelian randomization. This is a relatively new type of “data science hack” being used to analyze health risks, says Karmel Choi, a postdoctoral research fellow in psychiatric genetics at Massachusetts General Hospital and the Harvard T.H. Chan School of Public Health, who led the new study.

With Mendelian randomization, scientists zero in on small snippets of genes that vary from person to person. These variants are passed out before birth and do not change afterward; they are not altered by upbringing. Thanks to large-scale genetics studies, scientists have associated many of these snippets with specific health behaviors and risks. People with certain gene variants are, for example, more likely to overeat or be physically active than people without that variant.

More recently, scientists realized that these differences in people’s DNA offered, in effect, ready-made randomized trials designed by nature, since the variants occurred in mathematically random fashion.

Because of that inherent randomization, scientists could crosscheck the numbers of people with or without a snippet related to a health risk or behavior, such as, say, a strong likelihood to exercise, against another health outcome, such as severe depression. And if a large percentage of people with the variant did not develop the condition, scientists felt they could conclude that the behavior related to that variant caused the change in risk for the other condition.

And that result is what Dr. Choi and her colleagues found when they applied Mendelian randomization to exercise and depression. To reach that conclusion, they turned first to the UK Biobank, an enormous database of genetic and health information for almost 400,000 men and women. There they identified people who carried at least one of several gene variants believed to increase the likelihood someone will be active. Most of those people were active, and few of them had experienced depression.

People without the snippets, meanwhile, tended to move less, and they also showed greater risks for depression.

Delving deeper, the scientists found that, statistically, the ideal amount of exercise to prevent depression started at about 15 minutes a day of running or other strenuous exercise. Less-taxing activities like fast walking, housework and so on also afforded protection against depression, but it took about an hour a day to have an effect.

Finally, to be sure that physical activity was affecting the risk for depression, and not the other way around, the scientists repeated the Mendelian style of analysis on a separate large genetic database. This time they looked for gene variants related to depression and whether people who carried those variants and a propensity for depression tended to be physically inactive. It turned out, they did not.

So, the researchers concluded, physical activity in this analysis lowered the risk for depression, but depression did not affect whether people exercised.

Mendelian randomization remains a mathematical exercise, of course, and in the real world, people’s lives and behaviors are shaped by more than genetics. Many factors no doubt play a role in who develops depression. The gene variants related to being active could, for instance, also and separately play some kind of antidepressant role, Dr. Choi says, adding that the intertwined genetic and behavioral linkages between exercise and mental health will require many more studies to disentangle.

But already these results do provide “strong evidence” that being physically active, whatever your genetic makeup, can help protect against depression, Dr. Choi says.

How Many Push-Ups Can You Do? It May Be a Good Predictor of Heart Health

How Many Push-Ups Can You Do? It May Be a Good Predictor of Heart Health

Could push-ups foretell the future and the state of a person’s heart?

A new study in JAMA Network Open hints that this might be the case. It finds that men who can breeze through 40 push-ups in a single exercise session are substantially less likely to experience a heart attack or other cardiovascular problem in subsequent years than men who can complete 10 or fewer. The results suggest that push-up ability might be a simple, reliable and D.I.Y.-in-your-living-room method of assessing heart health, while at the same time helpfully strengthening the triceps and pectorals.

As almost all of us know, cardiovascular disease is the most common cause of death globally. Heart attacks and strokes also lead to considerable disability, lost work time and otherwise circumscribed lives and abilities.

But avoiding or treating cardiovascular disease requires recognizing that it might have begun or is on the horizon. Many medical tests of heart health, however, such as treadmill exercise-stress testing or heart scans, are expensive and complicated and can be difficult to interpret.

Many of these tests also generally are designed to pick up heart disease after it has started, not to predict the likelihood that it might develop. Meanwhile, mathematical risk scores that evaluate information about a person’s weight, cholesterol profile, smoking history and other health data are predictive, but in a way that is broad, impersonal and abstract.

Physicians and the rest of us who rely on our hearts have had little ability to evaluate cardiovascular health and the risk for future problems in a simple, scientifically valid, personalized and visceral way.

That void prompted researchers at Harvard University, Indiana University and other institutions recently to consider the health and fitness of a group of more than 1,500 Indiana firefighters. The firefighters reported each year to a single clinic in Indiana for a medical checkup that included the standard assessments of each firefighter’s weight, cholesterol, blood sugar and other health data. They also completed a submaximal treadmill stress test that estimated their current endurance capacity.

The researchers originally were most interested in that last measurement. Plenty of past studies have linked high aerobic fitness with a reduced risk for later heart disease and vice versa. The researchers thought that they might be able to quantify how well the treadmill test predicted future heart problems by using the database of firefighters’ health information.

So, they gathered information about each man’s stress test results — few women were working as career firefighters in this group, so only men were included. They also recorded any cardiovascular problems reported to or uncovered by clinic physicians in the 10 years after each firefighter’s first appointment. The data about heart problems was fairly comprehensive, since the firefighters needed their physician’s approval to return to work after even minor heart concerns.

The researchers planned to compare stress test results to subsequent cardiovascular problems to get a sense of how prescient the treadmill testing might be.

Then, almost incidentally, the researchers noticed that more than 1,100 of the firefighters also had completed push-up tests during their yearly exams. That testing had been bracingly analog: a clinic staffer counted how many push-ups each man could complete before his arms gave out or he reached 80 and was told he could quit showing off and stop.

Since they had the push-up data, the researchers slipped it in as a second data set in their examination of current fitness and later heart problems, categorizing the men by how many push-ups they could complete: zero to 10; 11 to 20; 21 to 30; 31 to 40; and 40-plus.

They then ran numbers.

And to their surprise, push-up capability proved to be a better predictor, statistically, of future heart problems than the treadmill tests.

Men who could complete at least 11 push-ups had less risk of developing heart problems in the following decade than those who could complete fewer than 10, they found.

This risk reduction mounted impressively at the highest level of push-up ability. Those men who could get through 40 or more push-ups had 96 percent less risk of heart problems in the next 10 years than those who quit at 10 or fewer.

The findings suggest that push-up capability might be an easy-to-use marker of cardiovascular disease risks, the researchers concluded, at least in men who resemble the firefighters.

Of course, this study was observational. It can show that more push-ups are linked with fewer heart problems, but not that arm strength directly improves heart health or whether becoming able to do more push-ups will drop the risk for heart problems over time. It also cannot tell us how the two might be linked.

But “muscular strength is one component of good fitness,” says Dr. Stefanos Kales, a professor of medicine at Harvard Medical School and senior author of the new study.

Push-up proficiency probably also indicates an interest in healthy eating, regular exercise and normal weight, he says, all of which could contribute to stronger hearts.

Best of all, push-up testing is simple, requiring only the ability to count. If that count should end before 10, however, you may want to talk to your doctor or a trainer about how to increase your fitness and strength and perhaps better protect your heart, Dr. Kales says.

What Women Find in Friends That They May Not Get From Love

What Women Find in Friends That They May Not Get From Love

SARA and I met as office drones in 1999. We became friends in a period of our lives when the demands of our jobs were just heating up, when the roots we were putting down in the city were just getting deep. In each other, we found respite, recognition, a shared eagerness to relax, take stock and talk about it all.

Many other women were doing the same things. Female friendship has been the bedrock of women’s lives for as long as there have been women. In earlier eras, when there was less chance that a marriage, entered often for economic reasons, would provide emotional or intellectual succor, female friends offered intimate ballast.

These days, marriages ideally offer far more in the way of soulful satisfaction. But they tend to begin later in life — today 20 percent of Americans ages 18 to 29 are married, compared with nearly 60 percent in 1960; the median age of first marriage for women has risen to 27 — if they marry at all. The marriage rate hit a record low in 2015, and a 2014 Pew Research Center study showed a significant number of adults had never been married and predicted that a quarter of millennials might never marry.

As women live more of our adult lives unmarried, we become ourselves not necessarily in tandem with a man or within a traditional family structure, but instead alongside other women: our friends.

Among the largely unacknowledged truths of contemporary female life is that women’s foundational relationships are as likely to be with one another as they are with the romantic partners who, we’re told, are supposed to complete us.

My relationship with Sara had a low-slung thrum of beer, cigarettes and the kind of quotidian familiarity we think of as exclusive to long-term mates, or possibly siblings. We played cards and watched award shows and baseball and presidential debates together; we shared doctors and advised each other on office politics; we gossiped and kept each other company when the exterminator came to behead the mice. (Seriously: This was the exterminator we both used, and he beheaded mice.)

Together, Sara and I had a close network of four other friends with whom we vacationed, but also maintained separate relationships with our own circles. Without realizing it, we were recreating contemporary versions of very old webs of support. The historian Carroll Smith-Rosenberg has written about women’s relationships in the 19th century that “friends did not form isolated dyads but were normally part of highly integrated networks.”

Friendships provided the core of what I wanted from adulthood — connection, shared sensibilities, enjoyment. Unlike my few youthful romances, which had mostly depleted me, my female friendships were replenishing, and their salubrious effect expanded into other layers of my life: They made things I yearned for, like better work, fairer remuneration, increased self-assurance and even just fun, seem more attainable.

Female friendship was not a consolation prize, some romance also-ran. Women who find affinity with one another are not settling. In fact, they may be doing the opposite, finding something vital that is lacking in their romantic entanglements, and thus setting their standards healthily higher.

Four years after we first met, the man Sara had been seeing was offered a job in Boston. They dated long distance for a year. But then they had to make a decision; he was intent on staying in Boston, even though it was not a city that offered her much professional opportunity.

Watching Sara wrestle with her choices was painful. It was the kind of upheaval, in our late 20s, that was messy enough to make me consider whether early marriage might have been wise after all. When we’re young, after all, our lives are so much more pliant, can be joined without too much fuss. When we get older, the infrastructure of our adulthood takes shape, connects to other lives. The prospect of breaking it all apart and rebuilding it elsewhere becomes a far more daunting project than it might have been had we just married someone at 22, and done all that construction together.

The day Sara moved to Boston, after weeks of packing and giving away her stuff, a bunch of friends closed up the U-Haul and gave long hugs and shouted our goodbyes as she drove off. When she was gone and I was alone, I cried.

Make no mistake: I believed that Sara should go. I wanted her to be happy and I understood that what we wanted for ourselves and for each other was not only strong friendships and rewarding work, but also warm and functional relationships with romantic and sexual partners; both of us were clear on our desires for love, commitment, family. Yet at the time, I was so gutted that I wrote an article about her departure, “Girlfriends Are the New Husbands,” in which I contemplated the possibility that it’s our female friends who now play the role that spouses once did, perhaps better than the spouses did.

Historically, friendships between women provided them with attention, affection and an outlet for intellectual or political exchange in eras when marriage, still chiefly a fiscal and social necessity, wasn’t an institution from which many could be sure of gleaning sexual or companionate pleasure.

Because these relationships played such a different role from marriage in a woman’s life, it was quite realistic for commitments between women to persist as emotionally central after the marriages of one or both of them. Even the happiest of married women found something in their associations with other women that they did not have with their husbands. As Elizabeth Cady Stanton, devotedly wed and mother of seven, once said of her activist partner, Susan B. Anthony, “So closely interwoven have been our lives, our purposes, and experiences” that when separated, “we have a feeling of incompleteness.”

SIX months after she moved to Boston, Sara came back.

She came back because the relationship she’d traveled to Boston for wasn’t fulfilling. More important, she came back because the life she’d left in New York — her work, her city, her friends — was fulfilling. She came back for herself. She says now that it was a New York job listing that was the beacon: “It was telling me to return to the life that fed me, my circle of friends, to return to myself.” I was sad that her relationship hadn’t worked out, but happy that she had built a life on her own that was satisfying and welcoming enough to provide her with an appealing alternative. And I was thrilled to have her back.

But divides can creep in between friends just as easily as they do in marriages. Maybe because she was nursing painful wounds as she rebuilt her New York life, and was resistant to simply falling back into her old patterns; maybe because, after the pain of having to say goodbye, I was gun-shy about giving myself over so completely, our friendship was never again quite as effortless as it had once been. “It was a rough re-entry,” she said recently of that time. “I knew of course that your life had continued while I was gone and that your circles of friends had expanded, but I was sad that we couldn’t slip right back into the space where we had left off.”

Then, a couple of years after her return, it was I who fell in love, I who suddenly couldn’t go out multiple nights a week with my girlfriends, because I had met a man with whom — for the first time in my life — I wanted to spend those nights.

When I met Darius, I was stunned by how much time I wanted with him, and also by the impossibility of living my social life as I had before. And once I took out the constancy of communication with my female friends, the dailiness and all-knowingness, the same-boatness, the primacy of our bonds began to dissipate.

We have no good blueprint for how to integrate the contemporary intimacies of female friendship and of marriage into one life. In this one small (but not insignificant) way, I think, 19th-century women were lucky, with their largely unsatisfying marriages and segregation into a subjugated and repressed gender caste. They had it easier on this one front: They could maintain an allegiance to their female friends, because there was a much smaller chance that their husbands were going to play a competitively absorbing role in their emotional and intellectual lives.

Sara says now that she was surprised to see me disappear so completely into a relationship, after having known me for years as the one who didn’t have (or need) a stable romantic partnership. I was the one who was far more into my work and my friends, the one who was so rarely in a relationship that I’d already begun planning to have a child on my own, the one who was familiar with the turning away of friends toward traditional relationships. Now hereI was, making that turn myself. “I was happy for you,” Sara told me. “But it felt like we’d switched roles; I woke up one morning as the independent feminist and you were the girl who was so into her boyfriend.”

The worrywarts of the early 20th century may have been right about the competitive draw of female friendship, about the possibility that it might inhibit or restrain a desire for marriage, especially bad marriages. But the real consequence of having friendships that are so fulfilling is that when you actually meet someone you like enough to clear the high bar your friendships have set, the chances are good that you’re going to really like him or her. That’s what happened to me.

For many women, friends are our primary partners through life; they are the ones who move us into new homes, out of bad relationships, through births and illnesses. Even for women who do marry, this is true at the beginning of our adult lives, and at the end — after divorce or the death of a spouse.

There aren’t any ceremonies to make this official. There aren’t weddings; there aren’t health benefits or domestic partnerships or familial recognition. There has not yet been any satisfying way to recognize the role that we play for one another. But, as so many millions of us stay unmarried for more years, maybe there should be.

The Value of Childhood Crushes

The Value of Childhood Crushes

When my daughter was in preschool, she came home one day starry-eyed and breathless, gushing about a 4-year-old in her class. “I love him,” she swooned. “Sooo much.” Downplaying her theatrics, I tried changing the subject. She changed it back. I was baffled. That kind of love isn’t for children — is it?

As classroom Valentine’s Day card exchanges give parents an opening to talk to kids about crushes, here is some expert insight into children’s early inklings of romance, and tips on how to respond.

Believe Them
Do children really fall in love? Amanda Rose, a professor of psychology at the University of Missouri who focuses on friendships and peer relationships in childhood and adolescence, has researched romantic interests in children as young as third and fifth grade, half of whom report having a boyfriend or girlfriend — a percentage that goes down with age. The difference, she said, is that the younger children are less likely than adolescents to have reciprocal romances. An elementary school-age child might never be aware of being a classmate’s object of affection.

“What we’re capturing with those younger kids is probably crushes,” Dr. Rose said. And although there’s little research about crushes for children younger than third grade, many adults recall infatuations at those young ages — and we see them in our children.

Dr. Rose likens young kids’ crushes to other types of pretend play such as playing house or ambulance driver: It is a kind of practice.

“In research on children’s social and cognitive development, those activities are discussed as very important in terms of trying out, at a very rudimentary level, adult roles,” she said. “I could see crushes as very similar.”

Deborah Roffman, a human sexuality educator and author based at the Park School in Baltimore, said crushes are “a normal part of development, when kids start to see each other in ways that are a little bit different. I really do believe that they get a little zing in their heart.”

“I clearly recall falling in love with my second-grade teacher,” said Greg Smallidge, an independent sexuality educator based in Seattle who trains teachers and works with students in schools and community programs. But for parents, he said, “to appropriately allow our kid this normal thing is challenging because it does dip into our fears.”

“Parents are more confused than ever about what’s truly age-appropriate,” Ms. Roffman said.

Sex, of course, is not for children. But love and romance can be for anyone.

Validate Them
As a writer on sex education, I often speak in schools. I’ve met parents who cringe in talking about how their preschool- or elementary school-age child has enacted romantic behaviors with other kids, for example, by holding hands, talking about kissing or naming a classmate they plan to marry. They often suspect the behavior is problematic.

That’s in contrast to what I’ve observed of the Dutch approach to sex education, which emphasizes healthy relationships and normalizes early flutterings of children’s hearts.

When I researched school sex ed in the Netherlands, one of the world’s most sexually healthy and gender-equal countries, I found that Dutch speakers use the term verliefd zijn — “being in love” — with equal credence for children, teenagers and adults.

For Americans, being “in love” is usually reserved for older teenagers and adults. We use trivializing terms like “puppy love” or “boy crazy” for younger adolescents, and it’s arguable we have no everyday language at all for the romantic thoughts of small children.

Instead of brushing aside young children’s crushes, Ms. Roffman suggested simply reflecting back to the child that you are listening: “Oh, so you have some special feelings for that person.” That can invite the child to open up.

Dr. Rose suggests finding a middle ground between underreacting and overreacting, even if a child’s infatuation seems trifling. “Maybe you also think it’s silly that they don’t like broccoli, but that’s how they feel, and as little humans their feelings deserve to be respected.”

Acknowledging and age-appropriately supporting kids’ crushes (“How’s Sarah doing? Oh, you got to sit by her? That must have been fun!”) can be a valuable early opportunity, she said, to open trustworthy lines of communication with our kids about love, relationships and, eventually, healthy sexuality.

Dr. Rose cautioned against teasing. Asking kids of any age about whether they have a boyfriend or girlfriend may send unintended messages about gender issues or sex, or make them feel too embarrassed to open up about love in the future. As a neutral conversation opener, you might ask if your child’s classmates talk about having crushes.

Model Respect
It can be especially important for boys to hear that it is good to have tenderhearted feelings. Research shows that American boys want intimacy and romance at the same rate as girls — but by admitting to that, they risk being seen as unmasculine.

With regard to the #MeToo movement, Dr. Rose said, we also can respond to children’s crushes by showing consideration for the object of their affection. It is an opportunity to reinforce an age-appropriate lesson about consent, even if the level of touching in the relationship amounts to nothing more than holding hands.

When engaging kids in conversation about the apple of their eye, Ms. Roffman suggests trying not to lead with questions that are gender-stereotyping or superficial (“Is she cute?”). Instead, she said, try asking, “What do you like about that person? What do you notice about them? What’s their personality like?” Kids also need to know that it’s normal to have crushes on someone of the same sex or gender.

Expect Things to Fizzle
Dr. Rose said it’s helpful to learn young to deal with breakups. “It’s the beginning of trying to experience what those emotions feel like and learning how to manage them. If you have a crush and he says something not very nice to you, or he ignores you, then that is a first opportunity for a 10-year-old to process, well, how do you manage those feelings?”

If families allow children to have play dates with their crushes, Mr. Smallidge said, they should help select activities suitable for the children’s age. Spending time together with a crush can be as simple as playing together at the park or getting ice cream, just as children would do with other friends.

One option, of course, is to do nothing at all about a crush except to savor it. “That is so safe,” Mr. Smallidge said. “That’s such a delicious feeling. One of the messages that would be nice for kids to hear is that they don’t have to do anything about crushes. A crush has its own value because it opens us up and it’s exciting. And most of them, I would say, end there.”

Loneliness Is Bad for Your Health. An App May Help.

Loneliness Is Bad for Your Health. An App May Help.

Loneliness is bad for your health. Social isolation is associated with a significantly increased risk of premature death. And the problem resists fixing; solitary people who participate in experiments meant to nudge them into joining groups tend to have high rates of recidivism. According to a study published this month in Proceedings of the National Academy of Science, however, it might be possible to reduce loneliness by using cellphones to teach a particular type of meditation.

Researchers from Carnegie Mellon University and several other institutions recruited 153 men and women who considered themselves stressed out — the study was slightly mischaracterized to disguise a primary concern, loneliness. Next, the volunteers completed questionnaires: They were asked about their social networks, their interactions with others and their feelings of loneliness, if any. Their baseline levels of sociability were established through texts that prodded them to answer questions about what they were doing and with whom. This monitoring lasted three days.

The subjects were then randomly divided into three groups and given an app for their phones. The app gave the control group general techniques for coping with stress. Another group was taught mindfulness through the meditative method of paying close attention to the moment and focusing on breathing and other sensations. The third group received those and additional instructions: Take note of and say “yes” aloud to all sensations, a process that trained the subjects to be attentive and approach what the researchers dubbed “equanimity.” Every day for two weeks, the subjects were tasked with using their app for 20 minutes and practicing for another 10 minutes. Afterward, they filled out the questionnaires again and went through another three days of monitoring.

Little changed for those in either the control group or the one taught attention-only mindfulness. But the subjects whose training included acceptance and equanimity were measurably more sociable. Their daily routines, after using the app for two weeks, typically included several more interactions with people that lasted at least a few minutes, and their questionnaires showed a decline in their feelings of loneliness.

Because loneliness, like mindfulness, is a subjective state, it’s difficult to make definitive conclusions about why and how a focus on acceptance prompted greater sociability. But David Creswell, an associate professor of psychology at Carnegie Mellon who conducted the study with the lead author, Emily Lindsay, believes that “the equanimity piece is key.” The poise it teaches, he says, may help people become less self-judgmental, less self-conscious, more amenable to interacting with others.

“People who are lonely usually feel bad about themselves because they are lonely, making it harder for them to put themselves in social situations,” Creswell says. A certain kind of mindfulness might help people “care less about feeling bad.” They might attend the party they would otherwise skip.