Study: No Good Evidence Weight Loss Supplements Work

Denise Mann wrote . . . . . . . . .

Losing weight is hard, but many weight loss supplements promise to make the journey easy. Unfortunately, there’s little high-quality research to back these claims, a new study shows.

Hundreds of weight loss supplements like green tea extract, chitosan, guar gum and conjugated linoleic acid are being hawked by aggressive marketers. And an estimated 34% of Americans who want to lose weight have tried one, according to the researchers.

“The temptation is great because someone has a megaphone, but you don’t need a celebrity endorsement and/or splashy headlines to tell you how to lose weight. The medical establishment will speak loudly and clearly when there’s something to say,” said study co-author Dr. Srividya Kidambi, an associate professor and chief of endocrinology and molecular medicine at the Medical College of Wisconsin.

To find out if 14 weight loss supplements and/or alternative therapies like acupuncture do what they claim, researchers identified 315 randomized-controlled trials, which are considered the gold standard in clinical research. Of these, 52 studies were deemed unlikely to be biased. Just 16 studies showed differences in weight between participants receiving treatment and those in the placebo arm.

The weight loss in these studies ranged widely, from less than 1 pound to just under 11 pounds. Weight loss was not seen consistently for any one weight loss treatment, and many had conflicting results, with some studies showing weight loss and others showing no such effect.

The studies included in the review looked at chitosan, a complex sugar formed from the hard shells of shellfish; ephedra or caffeine; green tea; guar gum; the tropical fruit extract Garcinia cambogia; chocolate/cocoa; conjugated linoleic acid, a natural substance produced in the gut by digestion of fats; white kidney bean (Phaseolus vulgaris); and calcium plus vitamin D, among others. Alternative weight loss therapies evaluated in studies included acupuncture, mindfulness, hypnosis and meditation.

“The dietary supplement industry is a Wild West of herbs and over-the-counter pills that have a lot of claims and little to no evidence supporting those claims,” said study co-author Dr. Scott Kahan, director of the National Center for Weight and Wellness in Washington, D.C. “We all want a magic pill, but dietary supplements aren’t the magic pills that they are marketed to be.”

There are things that are proven to help you lose weight and keep it off, Kahan said.

“Support from a dietitian, nutrition education and, in some cases, medication or weight loss surgery can all aid weight loss,” he said.

The study authors issued a statement calling for tighter regulation of supplements and more high-quality studies to assess the risks and benefits of weight loss supplements. The study appears in the June 23 issue of Obesity.

Their work comes on the heels of another study that found weight loss supplements mostly ineffective. That research was presented virtually last month at the European Congress on Obesity and published in the International Journal of Obesity.

In the United States, supplements aren’t regulated in the same way that pharmaceuticals are so there is no way to know if you are actually getting what you’re paying for, said Kidambi.

Most weight loss supplements won’t cause any harm, but many peddle false promises, she said. “If supplements take the place of diet, regular exercise and behavior changes, they will harm you in the long run,” she added.

Some supplements sold online may be laced with ingredients that are harmful and banned in the United States, Kidambi noted.

Weight loss supplements can also be pricey, she said.

It’s buyer beware when it comes to weight loss supplements, agreed Dr. Louis Aronne, founder and director of the Comprehensive Weight Control Program at New York-Presbyterian Hospital/Weill Cornell Medical Center in New York City.

“There is very little research demonstrating that currently available supplements produce significant weight loss,” said Aronne, who was not involved in the new study.

Andrea Wong is senior vice president of scientific and regulatory affairs at the Council for Responsible Nutrition, a Washington, D.C.-based trade group representing the supplements industry.

Wong, who has no ties to the research, pointed out that the new study did not include all of the dietary supplements on the market today, some of which may aid in weight loss efforts.

“Consumers should be wary of products that promise to make weight loss easy and to always talk to a health care practitioner for advice on responsible supplement use and weight management programs,” she said.

Source: HealthDay

Could Fish Oil Supplements Help Fight Depression?

Robert Preidt wrote . . . . . . . . .

Fish oil supplements are often touted as good for your heart health, but a new study finds they may also help fight depression.

“Using a combination of laboratory and patient research, our study has provided exciting new insight into how omega-3 fatty acids bring about anti-inflammatory effects that improve depression,” said lead author Alessandra Borsini, a postdoctoral neuroscientist at King’s College London.

Borsini said it’s been known that omega-3 polyunsaturated fatty acids have anti-depressant and anti-inflammatory effects, but exactly how that happens has been unclear.

“Our study has helped shine a light on the molecular mechanisms involved in this relationship, which can inform the development of potential new treatments for depression using omega-3 PUFA,” Borsini said in a university news release.

Previous studies have shown that people with major depression have elevated levels of inflammation, but no proven anti-inflammatory treatments for depression exist.

The patient portion of this new study included 22 people with major depression.

Once a day for 12 weeks, they were given one of two omega-3 polyunsaturated fatty acids (PUFAs) — either 3 grams of eicosapentaenoic acid (EPA) or 1.4 grams of docosahexaenoic acid (DHA).

EPA and DHA are omega-3 PUFAs found in oily fish.

Byproducts of EPA and DHA were measured in the patients’ blood before and after treatment, and their depression symptoms were assessed.

Treatment with both omega-3s was associated with a significant improvement in depression, with an average 64% drop in symptoms for the EPA group and 71% in the DHA group. It does not prove cause-and-effect, however.

The findings were published June 16 in the journal Molecular Psychiatry.

The levels of EPA and DHA used in this study can’t be achieved by eating oily fish, the researchers noted.

Senior study author Carmen Pariante, a professor of biological psychiatry, said the research has provided vital information to help shape clinical trials of therapeutic approaches with omega-3 fatty acids.

“It is important to highlight that our research has not shown that by simply increasing omega-3 fatty acids in our diets or through taking nutritional supplements we can reduce inflammation or depression,” she said. “The mechanisms behind the associations between depression and omega-3 PUFA are complicated and require further research and clinical trials to fully understand how they work and inform future therapeutic approaches.”

Source: HealthDay

Reviews Find No Evidence Weight-Loss Supplements Work

Dennis Thompson wrote . . . . . . . . .

You’re getting no real benefit from taking weight-loss supplements like garcinia cambogia, green tea extract, glucomannan, conjugated linoleic acid or chitosan, two new reviews show.

Most of the clinical trials studied didn’t show these supplements producing any weight loss among users, the researchers said. In the rare cases where people did lose weight, they didn’t drop enough pounds to have a positive impact on their health.

“The results of our systematic review highlight that taking herbal medicines or dietary supplements is not an effective weight-loss strategy,” said lead researcher Erica Bessell, a doctoral student with the University of Sydney in Australia. “We would recommend that people trying to lose weight should save their money and seek out evidence-based care instead.”

This first comprehensive review of weight-loss supplements in 16 years combined the results of 121 clinical trials involving nearly 10,000 adults, according to the researchers’ presentation on Saturday before a virtual annual meeting of the European Congress of Obesity. The results have also been published in the International Journal of Obesity and the Diabetes, Obesity & Metabolism journal.

Weight-loss supplements are a $41 billion global industry, the researchers said in background notes. Hundreds of different weight-loss supplements are sold in the United States, and estimates suggest that about 15% of Americans trying to drop some pounds have tried one.

“People pay a lot of money on it, and they may put themselves at health risk as well because there’s limited regulation of dietary supplements in the United States,” said Dr. Scott Kahan, director of the National Center for Weight and Wellness, in Washington, D.C. “The fact that they are unlikely to get any benefit at all makes the practice of using them, spending a lot of money for them and potentially putting yourself at risk something that needs to be better appreciated by the public, I think.”

Of all the supplements studied, only white kidney bean (Phaseolus vulgaris) resulted in statistically significant weight loss compared to placebo, the researchers found. However, people only lost about 3.5 pounds, not enough to make a difference for their health.

Supplements with no scientifically proven benefit included:

  • Tropical fruit extracts like garcinia cambogia, mangosteen and African mango.
  • Green tea extract.
  • Plant-based substances like yerba mate, veld grape, licorice root and East Indian Globe Thistle.
  • Chitosan, a complex sugar formed from the hard shells of shellfish.
  • Glucomannan, a soluble fiber derived from the roots of the elephant yam.
  • Fructans, which are carbohydrates found in fruits and vegetables.
  • Conjugated linoleic acid (CLA), a natural substance produced in the gut by digestion of fats.

“Though most supplements were safe for use in the short-term,” Bessell said, “very few were found to produce clinically meaningful weight loss. Those that were found to result in weight loss had only been investigated in one or two trials. Many trials were assessed to have a high risk of bias, and the design and conduct of the trials was often inadequately reported. Thus, there is currently no evidence to recommend any of these supplements for weight loss.”

The largest proven risk from these supplements is to your pocketbook, the researchers added. But not in all cases.

In 2004, the U.S. Food and Drug Administration banned the sale of ephedra, a weight-loss supplement derived from an evergreen shrub used in Chinese and Indian medicine, due to serious safety risks that included heart attack, seizures, stroke and sudden death, according to the National Center for Complementary and Integrative Health.

Another supplement that poses safety problems are fructooligosaccharides, which at high doses have been found to cause severe gastrointestinal symptoms, Bessell noted.

However, dietary supplements are not regulated by the FDA, Bessell and Kahan noted. The agency only steps in when consumers complain.

“Any product can be marketed, and the FDA can only remove products from the market if there is evidence that the product is unsafe or if the product label is misleading in terms of listed ingredients or claims of benefit,” Bessell said.

Experts say some safety concerns regarding supplements arise from the fact that what’s on the label might not be what’s in the capsule you swallow.

According to Kahan, “Because of deregulation of the supplement field, we don’t even know that what’s on the package is actually in the supplement. That’s where harm can occur with any of them.”

There’s also the potential that a supplement might react to one of the prescriptions you’re taking, Bessell added.

“The possibility of drug interactions may be present with some supplements, so health professionals and consumers should be aware of this,” Bessell said.

“At the most basic level,” Kahan said, “consumers need to be aware this is a situation of caveat emptor. People often believe inappropriately that if it’s being marketed that it’s safe, that the FDA has approved it or signed off on it, and that’s not the case in terms of dietary supplements.”

Andrea Wong, Ph.D. is senior vice president of scientific and regulatory affairs at the Council for Responsible Nutrition, which represents the supplements industry. Commenting on the new study, she said consumers should make decisions on supplements on a case-by-case basis.

“There are safe, beneficial weight management dietary supplements on the market, along with supplements that help to fill nutrient gaps for consumers who do not get all the nutrients they need from food alone, especially when they are limiting calories or engaging in strenuous exercise,” Wong said. “Individuals should look for evidence supporting the specific weight management product they are considering, rather than rely on review articles that group together numerous disparate products and make sweeping conclusions about the effectiveness of an entire category.”

At the same time, Wong said, “CRN reminds consumers to be wary of products that make claims that seem too good to be true and to always talk to a healthcare practitioner for advice on responsible supplement use.”

Source: HealthDay

Could High-Dose Fish Oil Raise Odds for Atrial Fibrillation in Heart Patients?

Amy Norton wrote . . . . . . . . .

Many people take fish oil to protect their heart, but a new study suggests that prescription versions may raise the risk of a common heart rhythm disorder.

At issue are prescription-strength omega-3 fatty acids, which are naturally found in fish oil. The medications are often prescribed to people with very high triglycerides, a type of blood fat linked to increased risk of heart attack and stroke.

According to the American Heart Association, prescription omega-3s can lower triglycerides by 20% to 30% in most people.

But the medications are also controversial, because their ultimate benefits for the heart are unclear.

Now the new study — an analysis of five past clinical trials — suggests caution is in order. Overall, trial patients given omega-3s were over one-third more likely to develop atrial fibrillation (a-fib) than those given a placebo. The fish oil doses taken ranged from 0.84 grams to 4 grams per day.

A-fib is a common heart rhythm disorder, or arrhythmia, in which the heart’s upper chambers begin to quiver chaotically instead of contracting effectively.

A-fib is not immediately life-threatening, but it’s “not benign,” either, said Dave Dixon, one of the researchers on the study and an associate professor at Virginia Commonwealth University (VCU), in Richmond.

Over time, Dixon said, a-fib can lead to complications like heart failure or stroke.

Exactly how prescription-strength omega-3 could contribute to a-fib is unclear, according to Dixon.

However, the increased risk was fairly consistent across the trials — more consistent, in fact, than heart benefits were, said co-researcher Salvatore Carbone, an assistant professor at VCU.

In all five trials, there were more a-fib cases among omega-3 patients than placebo patients, though the difference in risk was not statistically significant in all studies.

But when the researchers pooled the results of all five trials, there was a clear result: Omega-3 patients were 37% more likely to develop a-fib than placebo patients were.

In contrast, only one trial showed that an omega-3 product could cut the risks of other heart conditions.

In that trial, dubbed REDUCE-IT, patients using a product called Vascepa (icosapent ethyl) saw their risk of “cardiovascular events” drop by 25%. That included heart attack, stroke and death from cardiovascular causes.

Even in that study, though, a-fib risk rose among omega-3 users, by 35%.

Why has only one trial found heart benefits? Again, it’s not yet clear, Dixon said.

But, he added, Vascepa is different from the fish oil products tested in the other trials. It contains only one omega-3, called EPA, while the other products contain a combination of EPA and DHA.

And in the REDUCE-IT trial, Dixon said, higher levels of EPA in patients’ blood correlated to lower cardiovascular risks.

That hints, he said, that focusing on EPA might be “the way to go in the future.” But the conflicting findings on the benefits of omega-3s — along with the potential risk of a-fib — highlight the need for more studies, the researchers said.

The analysis was published in the European Heart Journal — Cardiovascular Pharmacotherapy.

Findings on the heart benefits of fish oil have indeed been “inconsistent,” said Linda Van Horn, a member of the heart association’s nutrition committee and a professor at Northwestern University Feinberg School of Medicine, in Chicago.

And that includes low-dose, over-the-counter fish oil supplements.

“There are limited and inconsistent data regarding the benefit or risk of taking fish oil supplements,” Van Horn said.

So the heart association recommends eating two servings of fish a week instead. Van Horn said that fatty fish, such as salmon, trout, albacore tuna and herring, are the best sources of omega-3s.

The trials in the current analysis tested prescription-strength omega-3s. But Carbone said he would be cautious about over-the-counter fish oil supplements, too.

“We don’t know if over-the-counter products could have these same effects,” he said.

Over-the-counter fish oil is considered a dietary supplement, so it is not regulated by the U.S. Food and Drug Administration as a drug would be, Dixon pointed out.

Both he and Carbone said it’s best to talk to a doctor or pharmacist before starting any fish oil product — and that people on prescription omega-3s should speak with their doctor before stopping.

Source: HealthDay

Study: Fish Oil, Vitamin D Won’t Prevent Atrial Fibrillation

For people hoping to prevent the heart rhythm disorder known as “a-fib,” new research shows that taking vitamin D or fish oil supplements won’t help.

A-fib, also known as atrial fibrillation, affects more than 33 million people worldwide and is the most common type of abnormal heart rhythm. It can cause symptoms that affect a person’s quality of life, result in blood clots that can cause a stroke, and also lead to heart failure.

For the study, the researchers examined whether taking vitamin D supplements or omega-3 fatty acids found in fish oil might affect different kinds of a-fib, and whether some patients would be more likely to benefit or be harmed by the supplements.

Overall, the results were mostly consistent across the different types of a-fib and patient groups, according to lead author Dr. Christine Albert and colleagues. Albert is chair of the cardiology department at Smidt Heart Institute in Los Angeles.

The study, published March 16 in the Journal of the American Medical Association, follows a presentation by Albert at an American Heart Association conference last year.

“Our recommendation remains the same,” she said in a JAMA Network news release. “We do not support taking fish oil or vitamin D supplements to prevent atrial fibrillation.”

However, “unlike other recent trials that found increased risks of atrial fibrillation with higher-dose omega-3 fatty acid supplements, our study did not find a significantly increased risk of atrial fibrillation with one gram of fish oil per day, which is good news for individuals taking low-dose fish oil for other health conditions,” Albert said.

Her team also found that vitamin D supplements at 2,000 international units per day did not increase a-fib risk.

Source: HealthDay