Updated on Nov. 22, 2021
Health experts reveal what you need to know about weight loss supplements, including the possible risks, benefits, potential side effects, and research behind them.
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There’s no magic bullet when it comes to losing weight and keeping it off. Eating a healthy diet and getting regular exercise are the keys to sustained weight loss, says Scott Kahan, MD, the director of the National Center for Weight and Wellness in Washington, D.C. Over-the-counter weight-loss products often peddle false hope, and many are unregulated and unreliable (and sometimes even dangerous).
The U.S. Food and Drug Administration (FDA) does not regulate nutritional supplements in the same way that they monitor prescription medications, so there is no guarantee that you are getting what you pay for, he notes. Even FDA-approved weight loss medications won’t deliver on their own without lifestyle changes. Also, some manufacturers, may not carry out studies in humans, and those that do, may only include a small sample group or conduct the research for a very brief period of time.
That said, there is some science suggesting a handful of weight loss supplements may confer some weight loss benefits. However, make sure you discuss the options with your doctor—as you would with any supplement—before even considering these. You’ll want to make sure these aids won’t interfere with any medications you might be taking or worsen any conditions you may have.
$23.07
MCTs or medium-chain triglycerides are found in foods like coconut oil, while long-chain triglycerides (LCT) are found in most other foods. People use medium MCTs in smoothies, coffee, salad dressings, and more. The idea is that your body can burn medium MCTs faster than longer ones, meaning that their calories are less likely to end up on your waist and thighs. MCTs may help you feel fuller longer, and they may help curb appetite so you eat less. (Check out more of the best MCT oils recommended by experts.)
One review of 13 studies in a 2015 issue of the Journal of the Academy of Nutrition and Dietetics showed that replacing long-chain triglycerides with MCTs may improve weight loss efforts, albeit modestly. Participants lost about 1.25 pounds over a three-week study period. Those who consumed MCTs also showed decreases in waist and hip circumference and the amount of total body fat, the study showed.
“Further research is required by independent research groups using large, well-designed studies to confirm the efficacy of MCT and to determine the dosage needed for the management of a healthy body weight and composition,” the researchers conclude. Dr. Kahan agrees with these conclusions.
“It makes sense that MCTs would be helpful with metabolism, but when we actually look at the evidence there is little to no high-quality studies that show a benefit for weight loss yet.” (Here are 50 things doctors wish you knew about weight loss.)
$17.88, pack of 6
High-quality tea is a great source of antioxidants and caffeine, says Sharon Zarabi, RD, CDN, bariatric program director at Lenox Hill Hospital in New York City. But, she cautions, drinking green tea does not directly burn stubborn belly fat like most pills tout.
That said, caffeine can maximize your energy for a workout. “This, coupled with a high-intensity activity, creates the perfect synergistic pow wow for burning body fat,” she says. Another weight loss plus: “Warm liquids tend to make us feel full as they sit in the stomach longer.”
As far as reducing appetite, a high-grade green tea leaves a bitter taste which can deter us from wanting to eat more.”Her advice? A cup of green tea as part of an overall healthy, low-calorie diet may fuel your workouts and help you shed those extra pounds.
$31.95
As seen on Shark Tank, these post-meal lozenges are gaining in popularity. “They help put a brake on overeating via two mechanisms,” says Julie Upton, MS, RD, and co-founder of Appetite for Health. “First, they make you mindful of what you’re eating. Second, they are designed to trigger sensory and physiological changes that can help individuals feel satisfied and reduce cravings or desires for sweets.” (Try these 13 simple tricks to stop your sugar cravings or cut sugar from your diet.)
$19.95, 240 count
The one factor that best predicts your weight loss success is… your fiber intake, according to a 2019 study in The Journal of Nutrition. Psyllium fiber is popular among keto eaters (it helps them stay regular).
One study in a 2017 issue of the Journal of the American Association of Nurse Practitioners found that people who supplemented their diet with psyllium lost about seven pounds during a six-month study, and they were less likely to gain back the weight than people on other types of fiber supplements. “This is essentially Metamucil reformulated to be a satiety supplement rather than a laxative,” says Upton. “I recommend taking it about 20 minutes before meals.”
As a bonus, psyllium fiber supplements may also help control blood sugar, insulin, and LDL (bad) cholesterol. (Here are 13 supplements and vitamins that may help with weight loss.)
$39.94, 60 count starter pack
Approved by the FDA, alli is the over-the-counter version of the prescription weight loss pill Orlistat. Orlistat helped people lose about 6.6 pounds over a year, according to a study in Drug Safety. “It prevents the body from absorbing fat in the diet by blocking the digestive enzyme lipase,” says Zarabi.
Blocking dietary fat only means your body is not absorbing fat and expels it through your bowel movements. The side effects include stomach cramps, loose, smelly, and frequent stools and loss of water weight, she says. Kahan adds that “alli works and side effects can be minimal if it’s used appropriately.”
$19.99, 120 count
Turning up in supplements like GNC Total Lean Phase 2 Carb Controller, white kidney bean extract (Phaseolus vulgaris) is a “starch blocker,” according to ConsumerLab.com, an independent testing firm in White Plains, New York. “Taking white kidney bean extract before meals may help fat loss (particularly if you eat a high starch diet) and, if combined with a sensible diet and exercise, [help] with modest weight loss,” the group notes.
The Office of Dietary Supplements (ODS) agrees that this starch blocker may help you lose some weight. “There is no substitute for a healthy diet and regular exercise,” cautions Dr. Kahan. There are FDA-approved prescription weight-loss pills that really work too, he says. “Talk to your doctor about available medications.”
$24.99, 180 count
Green coffee beans are the raw version of those you grind for your morning cup of Joe. The Office of Dietary Supplements states that they might help you lose a small amount of weight. However, they might also cause headaches or urinary tract infections. These supplements contain caffeine, and if they are taken with other sources of caffeine, they might cause side effects such as nervousness and nausea, according to the FDA. (Here are hidden sources of caffeine.)
$20.99, 180 count
Conjugated linoleic acid (CLA) is a polyunsaturated omega-6 fatty acid found naturally in dairy products and beef. Some research hints that it may confer some weight-loss benefits by breaking down fat, Dr. Kahan says. But, and this is a big but, most of the studies are in animals or test tubes, not people, so it’s too early to say that CLA supplements can definitely promote weight loss. The ODS says that it can help you lose a small amount of weight and fat and that it seems safe.
$18.93, 60 count
Apple cider vinegar can help control blood sugar and improve digestion, Zarabi says. “ACV…like most kinds of vinegar, contains acetic acid which has been touted to block the absorption of sugar in the blood and thus helps reduce the release of insulin, which is a fat-storing hormone.” Still, it’s no magic bullet. “ACV does not undo any damage of a poor diet, but research has proven that it can balance blood sugars with a proper diet.” It’s also bitter tasting which can certainly kill your appetite, she says.
$22.49, 60 count
Probiotics are hot, and supplements are flying off of shelves due to the long list of benefits linked to a healthy, well-balanced gut. “It seems quite clear that the makeup of our gut bacteria has an impact on a number of health outcomes and one of those may be weight,” says Dr. Kahan. That said, little is known about which strain, if any, is most effective for weight loss. “Without question, the most valuable thing to support your gut biome is to minimize overuse of antibiotics,” he says. “Eating a diet rich in fruits, vegetables, beans, and nuts has been shown to be associated with much healthier microbiomes,” he says.
It’s still the Wild West out there, but researchers out of the University Laval in Quebec, Canada, placed 125 overweight men and women on a 12-week weight-loss diet, followed by a 12-week period aimed at maintaining body weight. The women who took two probiotics from the Lactobacillus rhamnoses family lost more weight, compared with their counterparts who did not take probiotics. The probiotics did not affect weight loss in men, according to the study, which appeared in a 2014 issue of the British Journal of Medicine. You can look for L. rhamnoses on the label of supplements or dairy products.
