Can I increase my testosterone levels through the foods I eat? And if so, which foods or diets work best?Many men, particularly as they age, are concerned about their levels of testosterone, the male sex hormone touted to build muscle, sex drive and vigor. But individual foods are unlikely to have an impact on testosterone levels — though drinking excessive amounts of alcohol might. If you are overweight, altering your diet to lose weight may help, since carrying excess pounds is a common cause of low testosterone. But in terms of specific foods or diets, any uptick you achieve may not have a noticeable impact on libido, energy or muscle mass.“If someone was not overweight, I wouldn’t put them on a specific diet to raise testosterone based on the data we have now,” said Alexander Pastuszak, an assistant professor of urology and surgery at the University of Utah in Salt Lake City, who co-authored a review on alternatives to testosterone therapyIn men, normal testosterone levels range from 300 to 1,000 nanograms per deciliter of blood. Ups and downs within that normal range are unlikely to have any impact on sex drive or vitality. Only when levels consistently drop below 300 points — as confirmed in two blood tests by an accredited laboratory — are symptoms like low libido, erectile dysfunction, fatigue, low mood or loss of muscle mass likely to appear, a medical condition known as hypogonadism.Starting at around age 40, men’s testosterone levels start to decline by about 1 percent per year. But the drop can vary tremendously, with some older men maintaining levels similar to healthy young men. The trajectory of falling testosterone is steeper among men who gain a lot of weight, said Dr. Shalender Bhasin, professor of medicine at Harvard and the director of the Research Program in Men’s Health: Aging and Metabolism at Brigham and Women’s Hospital..css-1xzcza9{list-style-type:disc;padding-inline-start:1em;}.css-3btd0c{font-family:nyt-franklin,helvetica,arial,sans-serif;font-size:1rem;line-height:1.375rem;color:#333;margin-bottom:0.78125rem;}@media (min-width:740px){.css-3btd0c{font-size:1.0625rem;line-height:1.5rem;margin-bottom:0.9375rem;}}.css-3btd0c strong{font-weight:600;}.css-3btd0c em{font-style:italic;}.css-1kpebx{margin:0 auto;font-family:nyt-franklin,helvetica,arial,sans-serif;font-weight:700;font-size:1.125rem;line-height:1.3125rem;color:#121212;}#NYT_BELOW_MAIN_CONTENT_REGION .css-1kpebx{font-family:nyt-cheltenham,georgia,’times new roman’,times,serif;font-weight:700;font-size:1.375rem;line-height:1.625rem;}@media (min-width:740px){#NYT_BELOW_MAIN_CONTENT_REGION .css-1kpebx{font-size:1.6875rem;line-height:1.875rem;}}@media (min-width:740px){.css-1kpebx{font-size:1.25rem;line-height:1.4375rem;}}.css-1gtxqqv{margin-bottom:0;}.css-19zsuqr{display:block;margin-bottom:0.9375rem;}.css-12vbvwq{background-color:white;border:1px solid #e2e2e2;width:calc(100% – 40px);max-width:600px;margin:1.5rem auto 1.9rem;padding:15px;box-sizing:border-box;}@media (min-width:740px){.css-12vbvwq{padding:20px;width:100%;}}.css-12vbvwq:focus{outline:1px solid #e2e2e2;}#NYT_BELOW_MAIN_CONTENT_REGION .css-12vbvwq{border:none;padding:10px 0 0;border-top:2px solid #121212;}.css-12vbvwq[data-truncated] .css-rdoyk0{-webkit-transform:rotate(0deg);-ms-transform:rotate(0deg);transform:rotate(0deg);}.css-12vbvwq[data-truncated] .css-eb027h{max-height:300px;overflow:hidden;-webkit-transition:none;transition:none;}.css-12vbvwq[data-truncated] .css-5gimkt:after{content:’See more’;}.css-12vbvwq[data-truncated] .css-6mllg9{opacity:1;}.css-qjk116{margin:0 auto;overflow:hidden;}.css-qjk116 strong{font-weight:700;}.css-qjk116 em{font-style:italic;}.css-qjk116 a{color:#326891;-webkit-text-decoration:underline;text-decoration:underline;text-underline-offset:1px;-webkit-text-decoration-thickness:1px;text-decoration-thickness:1px;-webkit-text-decoration-color:#326891;text-decoration-color:#326891;}.css-qjk116 a:visited{color:#326891;-webkit-text-decoration-color:#326891;text-decoration-color:#326891;}.css-qjk116 a:hover{-webkit-text-decoration:none;text-decoration:none;}Studies on foods or diets and testosterone levels have generally been small and the findings far from conclusive. A recent British review that pooled data from 206 volunteers, for example, found that men on low-fat diets had testosterone levels that were about 60 points higher, on average, than men on high-fat diets. Men who followed a vegetarian diet tended to have the lowest levels of testosterone, about 150 points lower, on average, than those following a high-fat, meat-based diet. Still, Joseph Wittaker, the lead investigator and a nutritionist at the University of Worcester in Britain, said he would not recommend a man increase the fats in his diet unless he had low testosterone levels and symptoms of low T and was already restricting fats.Another study in the Journal of Strength and Conditioning Research tested two styles of diets in 25 fit men between the ages of 18 and 30. Calories consumed were the same, but one group ate a high-fat, very-low-carb, ketogenic-style diet, consisting of 75 percent of calories from fats, 5 percent from carbohydrates and 20 percent from protein. Men in the other group ate a more traditional Western style, low-fat diet, containing 25 percent of calories from fats, 55 percent from carbohydrates and 20 percent from protein. After 10 weeks of eating the high-fat diet, testosterone increased by 118 points, on average, while after the low-fat diet, levels declined by about 36 pointsAileen Son for The New York TimesSimilarly, a study of 3,000 men found that those who reported eating a low-fat diet had slightly lower testosterone levels — about 30 points lower — than men who ate higher-fat diets. But none of the men had low testosterone.“The moral is that healthy men who are of normal weight with no significant comorbidities are unlikely to benefit from restrictive diets,” said Dr. Richard J. Fantus, one of the study’s authors and a urologist at NorthShore University HealthSystem in Evanston, Ill.Diet studies are complicated, because changing one component of the diet, such as fat intake, alters so many other things, such as the amount of carbohydrates, protein and micronutrients consumed. It’s unclear which component of the diet may have prompted the hormonal changes, Dr. Bhasin said. Furthermore, testosterone levels may also be shaped by how much a person sleeps, or whether they are jet-lagged, or if they are eating most of their calories at night or in small meals throughout the day.Dr. Faysal Yafi, chief of the division of Men’s Health and Reconstructive Urology at the University of California, Irvine, says his patients who opt to follow specific diets tend to start exercising more and drinking less alcohol, all of which can raise testosterone levels. He suspects any links between diet and testosterone may be the result of an overall healthier lifestyle.Some men worry that eating lots of soy foods may cause their testosterone levels to fall, because soy is rich in isoflavones, which mimic the structure of estrogen. But the evidence doesn’t support their concerns, even if men eat foods like miso, tofu or soy milk at every meal. (Doctors did report one anecdotal case in which a 19-year-old man with Type 1 diabetes who followed a vegan diet containing 360 milligrams of soy daily — nine times higher than a typical Japanese diet, and 100 times higher than the typical American diet — developed low testosterone levels along with low libido and fatigue. His symptoms improved when he stopped eating the soy-heavy, vegan diet.)Long-term alcohol abuse lowers testosterone by damaging cells in both the testes, which make testosterone, and the liver, which alters testosterone metabolism. But binge drinking every now and then does not appear to have much of an impact — it lowers testosterone for only about 30 minutes, according to one study, after which levels bounce back to baseline.Obese men who have low levels of testosterone can increase levels by cutting calories and losing weight — the type of diet does not matter, studies suggest. On the opposite extreme, Dr. Bhasin said he is seeing an increasing number of men at his clinic who have body dysmorphic issues and are suffering from low libido and fatigue. Strict calorie restriction, exercising intensely and being chronically stressed can all cause testosterone levels to plummet and are likely to blame, he said.The bottom line is that for otherwise healthy men who are following a reasonably healthy lifestyle, fiddling with specific foods or the composition of the diet is not likely to make much of a difference on the testosterone score card. As Dr. Fantus of NorthShore University put it: “I don’t think there is a way to game the system to get really large increases by changing the diet.”

The advent of wearable devices that monitor our heart rhythms both excites and worries doctors.By Sean DongOn a recent Saturday, my 87-year-old mother was feeling a bit woozy, so she pressed a button on the side of her Apple watch to reveal her ECG, a recording of her heart’s electric rhythm. Thirty seconds later, three messages appeared on the watch’s screen. One showed the characteristic zigzag spikes of the ECG, or electrocardiogram. The second revealed that her heart rate, usually 80 beats per minutes, was down to only 40. The third said the results were “inconclusive,” with the advice: “Call your doctor.”My mother is a hardy octogenarian. She walks about a mile every day, works out with a trainer (currently via Zoom) three times a week and, as she often used to say, planks nearly as well as her former sorority sister, the late Ruth Bader Ginsburg.After leaving a message with her doctor’s office, she called my brother, a doctor who lives nearby, and told him she was exhausted and “just not feeling right.” He came over immediately and took her to the emergency room.There, the hospital’s electrocardiogram, which provides a more detailed readout than the watch, showed that the electrical signals in the top part of the heart were not being transmitted properly to the bottom. Her heart was beating, but too slowly. The staff rushed her to the cardiac care unit, where doctors implanted a pacemaker the next morning.When she called a longtime friend to tell her the story, the friend responded that she’d likewise had a recent smartwatch scare: her heart rate was sky-high, reaching 182. Her doctor had her wear a Holter monitor, a medical-grade portable ECG device that monitors heart rhythm continuously, for four days and advised her to keep a diary of symptoms, such as chest pain or a skipped heartbeat. She didn’t notice any, and the report from the Holter device revealed that everything was fine.The advent of smartwatches that retrieve heart physiology both excites and worries physicians. In addition to Apple, a number of companies make wearable E.C.G. monitors for home use, including Samsung, Withing, Fitbit and AliveCor. And for every story like my mother’s, in which a warning leads to the placement a potentially lifesaving pacemaker, there are many more like her friend’s, in which minor variations in heartbeats lead to needless work-ups, treatments with risky side effects and lots of unnecessary anxiety.So are these wearables worth it?Conclusive evidence about their accuracy and cost effectiveness is lacking, though an Apple-sponsored study from 2019 published in The New England Journal of Medicine suggested they may help to detect some kinds of abnormal heart rhythms, particularly in the elderly. A slew of additional studies are underway, including ones to assess whether a smartwatch can actually help to save lives, or whether mobility measures such as step count lead to fewer heart attacks and hospitalizations.Most of these at-home E.C.G. watches are designed to record heart rate and detect atrial fibrillation, the most common irregular heart rhythm, which affects up to six million Americans. A-fib, as it’s called, increases the risk of strokes, leading to 150,000 deaths and 450,000 hospitalizations a year. But doctors say that many people have an irregular heartbeat every now and then that doesn’t have clinical implications.Like many new technologies that uncover things in the body that doctors don’t yet fully understand, these devices may alert the user about an irregular heartbeat, but not all irregularities are dangerous. “It’s like we just invented the microscope and are seeing microorganisms, and we don’t know what they are,” said Dr. Harlan Krumholz, director of the Center for Outcomes Research and Evaluation at Yale. “We are seeing things, and we aren’t sure if it denotes extra risk.”Most watches wait to send an alert until there have been about five abnormal beats within an hour or so, rather than after every altered rhythm. Still, that doesn’t mean the abnormality is dangerous.“As a cardiologist, I really like at-home devices,” said Dr. Gary Rogal, medical director of cardiovascular services at RWJBarnabas Health in West Orange, N.J., whose team cared for my mother. But he clarified he likes them only for patients in whom he feels there’s an indication to look for something, such as those with an existing heart condition or a family history of heart disease. “I would never subscribe to the concept that everyone should be monitored. You’ll see stuff and it will make you crazy, but you’re probably fine.”The American Heart Association agrees that smartwatch monitors could be beneficial, even lifesaving, for some, but Dr. Mariell Jessup, the group’s chief science and medical officer, said, “we do not have enough data yet to recommend it for everyone.”Even electrocardiograms performed at a doctor’s office aren’t routinely recommended for everyone. The U.S. Preventive Services Task Force, a group of experts that advises on screening tests, says there is not enough evidence to show that routine ECGs are effective and worries about the costs, and potential dangers, of further testing. And doctors worry that as more and more people wear these devices that might spot meaningless heart arrhythmias, there could be a flood of unnecessary follow-up testing and too much treatment.“That’s what keeps me up at night,” said Dr. Joseph Ross, a professor of medicine and public health at Yale who is among a team of investigators conducting a randomized clinical trial that compares a group wearing the Apple watch to a control group wearing a smartwatch without the E.C.G. app. “If someone with an occasional abnormal rhythm that would never have caused a stroke undergoes an extensive work-up or is put on a blood thinner, the risk of a dangerous bleed or other harm outweighs the benefits of potentially preventing a stroke.”Dr. Steven Lubitz, an associate professor of medicine at Harvard Medical School and cardiologist at Massachusetts General Hospital, fears that customers will think the watches provide a safeguard for overall heart health and assume, for example, they check for signs of heart attacks, which they do not.“Your mother’s story is the hope for all of these devices. In her case, the technology led to a diagnosis of a dangerously slow heart rate,” he said. “To date, most of the tech work on heart rate has been focused on detecting A-fib. Similar rigor may be required to validate the detection of other health conditions.” We may be on the verge of entering a new era of medicine in which patients can glance at their wrists to check their emails and heart rhythms and notify their physicians if something seems awry. In the perfect health care world, cardiologists envision a day where they can prescribe a watch or other small clip-on device to high-risk patients and insurance would cover the cost. Otherwise, the advent of new technology would only help those who can afford it, exacerbating health inequities.As Dr. Ross noted, “I want to see more scrutiny, to know whether these digital devices that consumers can purchase are making our patients’ lives better.”Two weeks after her surgery, my mother was doing her one-minute planks and lifting weights with her Zoom personal trainer. Maybe, without the watch, my mother would have been OK and just felt really tired until she called her doctor on Monday. Or maybe not.