The Health Trends Worth Trying—And a Few You Should Skip

Learn the science (or lack thereof) behind popular wellness crazes.

Every week, it seems, there’s a new diet, superfood, or remedy that a dewy-skinned celebrity promises will make you feel and look amazing. We can (mostly) thank Facebook and Instagram for causing wellness trends to spread like wildfire these days; the problem is that the science often lags far behind the hype. We talked to experts to find out if some of today’s hottest trends are worth trying—or if you’d be wise to stick with what’s tried-and-true.

CBD

Why it’s a trend: Short for “cannabidiol,” CBD is a chemical compound found in cannabis that has become über-popular because it won’t get you high but will, supposedly, help alleviate pain, anxiety, insomnia, PMS, and hangovers. Though CBD is in a legal gray area (check your state and local laws before purchasing), many shops and online stores sell CBD oils and powders that you can rub on your skin, vape, place under your tongue, or eat. Some cafés will even add it to your coffee (or empanada—seriously).

What science suggests: One CBD-based drug has been FDA-approved to treat two rare forms of epilepsy. But as for pain, anxiety, and all the other ailments, scientists mainly have data from animal studies—nothing that shows it treats conditions other than epilepsy in people. Even if CBD did cure everything under the sun, it’s unlikely to be effective at the tiny doses found in most over-the-counter products today, says neurobiologist Margaret Haney, PhD, director of Columbia University’s Cannabis Research Laboratory. “You need hundreds of milligrams of real CBD to even think you’re going to see an effect,” she says. “Five milligrams in your coffee is not going to do anything.” Verdict: Don’t bother with CBD products. Higher-concentration products may work, but they’re expensive and still not guaranteed. Wait until more options and research are available.

Prebiotics

Why it’s a trend: You’ve heard of probiotics: live microorganisms that have the potential to improve your gut health. Prebiotics are different. They are nondigestible types of fiber that nourish the healthy bacteria in your intestines. Celebrity nutritionists have touted prebiotics’ potential benefits.

What science suggests: Right now, the benefits of prebiotics are largely theoretical. “It’s a very promising field, but there have not been a lot of studies,” says Purna Kashyap, MD, a gastroenterologist at the Mayo Clinic in Rochester, Minnesota, and a member of the scientific advisory board at the American Gastroenterological Association’s Center for Gut Microbiome Research & Education. We don’t know which prebiotics are best for which people and which situations. The good news, says Kashyap, is that you can get potentially helpful prebiotics by eating a variety of fruits, vegetables, nuts, and seeds. Verdict: Don’t buy prebiotics from the store just yet. Nourish your gut bacteria with a varied, fiber-rich diet.

Foam rolling

Why it’s a trend: Many personal trainers claim that foam rollers release knots in your fascia, the bands of tissue that connect your muscles. In doing so, rollers supposedly ease muscle pain and improve muscle mobility and range of motion. Professional athletes swear by them: Emily Day, a member of the U.S. Olympic beach volleyball team, has written about how she rolls before weight lifting, after practices, and anytime her muscles feel tight.

What science suggests: Little research has evaluated the effects of foam rolling. For one thing, it’s difficult to study: The results may depend on the size of the roller and how much pressure is used. “Common advice I give is that it shouldn’t hurt you and may or may not help you,” says Allison Schroeder, MD, a physical medicine and rehabilitation doctor at the University of Pittsburgh Medical Center. One recent study did suggest that foam rolling for as little as 20 seconds at a time can improve range of motion. Verdict: Why not? Exercise is great for you, and foam rolling can make it feel even better.

Diets based on blood type and genes

Why it’s a trend: Popularized by naturopath Peter J. D’Adamo in his book Eat Right 4 Your Type ($10; amazon.com), blood type diets are based on the idea that your nutritional needs are determined by your blood type. Among other things, D’Adamo says that people with different blood types have different gut bacteria, which can digest certain foods better than others—so eating according to your blood type may reduce your risk for certain diseases and conditions. Testing companies, such as 23andMe, have also begun providing health advice based on people’s DNA.

What science suggests: In a 2018 study in the Journal of Nutrition, researchers found that people who ate diets supposedly aligning with their blood type were no less at risk of cardiometabolic disease than those who didn’t. Evidence suggested that “the theory behind this diet is not valid,” they concluded. Yoni Freedhoff, MD, founder and medical director of the Bariatric Medicine Institute in Ottawa, Ontario, agrees: These custom diets are “super nonsense at this point,” he says. Verdict: Forget it. To eat healthier, focus on having more veggies and less sugar.

Essential oils

Why it’s a trend: Who doesn’t want an all-natural, amazing-smelling health boost? According to Google Trends, interest in the aromatic plant products known as essential oils has climbed over the past ve years. They’re now used as massage oils, flavor enhancers, and ingredients in foods and personal-care products. Essential oil companies claim their products relieve stress, improve sleep, and promote the health of the heart and immune system.

What science suggests: Unfortunately, few clinical trials have tested the health effects of essential oils, and the ones that have “are usually quite flimsy,” in that they are small and poorly designed, says Edzard Ernst, MD, PhD, a complementary medicine researcher at the University of Exeter in England. Verdict: Enjoy their aromas all you want, but “do not expect them to cure major illnesses,” says Ernst. One possible exception: Several small trials suggest that capsules containing peppermint oil, taken at least twice a day, can improve symptoms of irritable bowel syndrome. So if you have IBS, talk to your doctor about trying them. Also, essential oil diffusers provide a more fire-safe way than scented candles to add fragrance to a room.

Meditation

Why it’s a trend: Between 2012 and 2017, the use of meditation by Americans more than tripled, according to the Centers for Disease Control and Prevention’s National Health Interview Survey. Gyms and yoga studios now offer it; progressive companies, such as Google and Nike, provide office meditation sessions for employees; smartphone apps can guide you through sessions at home. Many celebs, including Katy Perry, Oprah Winfrey, and Kristen Bell, say that meditation keeps them feeling great.

What science suggests: Clinical trials suggest that meditation—which involves trying to experience the present moment and observing and acknowledging your thoughts and feelings—can help treat or ease a number of ailments, including anxiety, depression, insomnia, and high blood pressure. “The health benefits of meditation have been proven time and again,” says licensed clinical psychologist Dana Harron, PsyD, director of Monarch Wellness & Psychotherapy in Washington, D.C. It’s unclear how meditation achieves these feats, but some research suggests it changes the brain over time. Verdict: If meditation can help you sleep better, keep you calmer, and make you happier, what’s not to love?

Blue-light-blocking glasses

Why it’s a trend: Some claim that the short-wavelength blue light we’re increasingly exposed to from our devices is damaging our eyes, and that glasses that block it will keep our eyes healthier. According to the American Macular Degeneration Foundation, research suggests that blue light may contribute to retinal damage and increase the risk of age-related macular degeneration, a leading cause of vision loss in people ages 50 and older.

What science suggests: In a 2017 review of three clinical trials, researchers in the U.K. and Australia analyzed whether people who wore blue-light-blocking glasses had less eye fatigue and better vision over time than people who didn’t. Their conclusion: Nope. It’s “a big urban myth,” says ophthalmologist and retina surgeon Abdhish R. Bhavsar, MD, a clinical spokesperson for the American Academy of Ophthalmology. Verdict: Skip the glasses. That said, some research suggests blue light can make it harder to fall asleep, so if you struggle with insomnia, avoid TV and devices right before bed, turn on nighttime settings if you have them, or consider blue-light-blocking glasses when you use devices in the evening.

Intermittent fasting

Why it’s a trend: Intermittent fasting is exactly what it sounds like: not eating for an extended period of time, from half a day to several days. Fasters claim it’s fabulous for weight loss, slows aging, and prevents chronic diseases. Celebs like Chris Pratt, Halle Berry, and Kourtney Kardashian have reportedly been on board.

What science suggests: In a 2018 clinical trial, researchers compared the 5:2 style of fasting—in which you eat normally for five days and then eat no more than 400 calories a day for two days—with a more traditional diet. After a year, the intermittent fasters lost as much weight as the traditional dieters. And no research shows that fasting prevents disease. “It appears intermittent fasting is just as good or as bad as any other diet,” says Freedhoff. Among people who are vulnerable to or have a history of disordered eating, the extreme restriction involved in this diet could pose risks. Verdict: Give intermittent fasting a shot if you want to—and your doctor gives the OK—but don’t expect miracles.