Your online search of “safe weight loss supplements” can return misleading reviews. This post will help you sort through the facts regarding weight loss supplement safety.
As the makers of the weight loss supplement Lovidia, we wish we could say that all weight loss pills and supplements are safe.
But rather than acting as a cheerleader for the weight loss supplement industry, we want to provide you with information you can use to make an educated decision about safety concerns regarding over-the-counter weight loss supplements and pills.
Several factors you should consider in your search for safe weight loss supplements are side effects associated with specific supplement ingredients as well as health risks and dangers due to interactions with medications.
The following summary of safety concerns associated with common over-the-counter weight loss supplement ingredients is compiled from published reviews of clinical trials.
Because this post focuses on supplement safety, we do not address questions of effectiveness here, except where an ingredient has been shown in clinical trials to be truly useless. We want you to be safe, as well as warn you about weight loss supplement ingredients that are a potentially dangerous waste of money.
For more information about specific ingredients, including benefits and evidence of effectiveness and products they are used in, please refer to our post, Understanding Weight Loss Supplements, Pills, Shakes & Vitamins.
Mode of Action
Contains the stimulant synephrine believed to suppress appetite
Known Side Effects and Health Risks
Chest pain, anxiety, headache, musculoskeletal pain, increased blood pressure and heart rate
Caffeine (including from herbs such as guarana, kola nut and yerba mate)
Stimulant that affects the central nervous system to suppress appetite
Jitters, anxiety, insomnia, nausea, diarrhea, depression, racing heart, high blood pressure, impaired adrenal function, potential for addiction
Capsaicin (cayenne pepper)
Some evidence suggests spicy foods have thermogenic properties to increase fat burning and energy (calorie) metabolism
Allergic reaction, skin rash; kidney and liver damage; Stomach irritation and heartburn, especially in people with irritable bowel syndrome or stomach or intestinal ulcers
Seen in testing on rats to inhibit production of an enzyme related to fat synthesis; results not replicated in any human trials
Dizziness, dry mouth, headache, upset stomach, diarrhea, jaundice, elevated liver enzymes, liver damage, liver failure
Glucomannan/ Konjac Root
Provides fiber to create a feeling of fullness and suppress appetite
Abdominal discomfort, flatulence, diarrhea, constipation
Green Tea Extract
Contains the antioxidant ECGC that increases a hormone associated with fat burning and metabolism
Generally safe, but in high concentrations, may produce herbal hepatotoxicity leading to liver damage/liver failure
Gut Sensory Modulation
Uses food-grade nutrients to activate satiety sensors in the gut and control hunger and suppress appetite
No safety flags noted in clinical trials
Marketers claim it stimulates release of a chemical compound similar to glucose; no impact on weight loss seen in clinical trials
Increased heart rate and blood pressure, headache, dizziness, nausea, vomiting
Marketed as a fat burner/metabolism booster despite no credible clinical evidence
Chemically related to the stimulant synephrine; might cause jitters, increased blood pressure and rapid heartbeat
FDA-approved drug that blocks an enzyme that breaks down fats, leaving them undigested
Gastrointestinal issues: loose stools, oily spotting, gas w/ discharge, urgent bowel movements, poor bowel control; Possible nutritional deficiency due to interference with absorption of fat-soluble vitamins A, D, E, K
Weight loss supplements are regulated by the U.S. Food and Drug Administration as food, not as drugs. This is an important distinction because it means the FDA essentially relies on the makers of weight loss supplements to be honest both about the ingredients they contain and that those ingredients are safe.
Similarly, since the FDA does not approve individual food labels, including the “active ingredients,” “supplement facts” and “other ingredients” on weight loss supplements. Rather, “FDA regulations require nutrition information to appear on most foods, including dietary supplements. Also, any claims on food products must be truthful and not misleading, and must comply with any regulatory requirements for the type of claim.”
Again, this puts the onus on weight loss supplement makers to be clear and truthful in their labeling. As you will see later, this is not always the case.
No. The FDA doesn’t test or approve weight loss supplements, stating, “Unlike new drugs, dietary supplements are not reviewed and approved by FDA based on their safety and effectiveness. Unless an exception applies, dietary supplements that contain a new dietary ingredient (a dietary ingredient not marketed in the United States before Oct. 15, 1994) require a notification to FDA at least 75 days before marketing.”
The notification must include the information, such as evidence from clinical trials, that provides the manufacturer’s or distributor’s basis for concluding that a weight loss supplement will “reasonably be expected to be safe.”
In a warning to consumers, the FDA says it has seen “an emerging trend where over-the-counter products, frequently represented as dietary supplements, contain hidden active ingredients that could be harmful.”
This is very important when considering whether a weight loss supplement is safe because you cannot always trust the label to show all the ingredients a supplement contains.
In its warning, the FDA continues, “Consumers may unknowingly take products laced with varying quantities of approved prescription drug ingredients, controlled substances, and untested and unstudied pharmaceutically active ingredients. These deceptive products can harm you! Hidden ingredients are increasingly becoming a problem in products promoted for weight loss.
“Remember, FDA cannot test all products on the market that contain potentially harmful hidden ingredients. Enforcement actions and consumer advisories for tainted products only cover a small fraction of the tainted over-the-counter products on the market.”
In a separate warning on health risks and dangers associated with weight loss supplement ingredients, the FDA notes that “… many dietary supplements contain ingredients that have strong biological effects which may conflict with a medicine you are taking or a medical condition you may have. Products containing hidden drugs are also sometimes falsely marketed as dietary supplements, putting consumers at even greater risk.”
When public health concerns arise about a weight loss supplement after the product is on the market, the FDA will research and evaluate the product’s safety and monitor adverse events.
In rare cases, the agency may even remove a product from the market if there is overwhelming evidence it is not safe.
In the 1990s and early 2000s, a number of weight loss supplement companies were using a Chinese herb called ma huang as an ingredient in their products.
Ma huang had been used for centuries in traditional Chinese holistic medicine. Also known as ephedra, it was a natural botanical with an exotic backstory, which made it an attractive herbal weight loss supplement ingredient from a marketing standpoint.
And it was an effective ingredient, at least in one regard. Ephedra contained an amphetamine-like stimulant called ephedrine that had properties that suppress appetite.
Consumers assumed that since ephedra was from an herb, it produced safe weight loss supplements.
Then, 23-year-old Baltimore Orioles pitcher Steve Bechler died while using ephedra, helping to prompt the FDA to undertake extensive research involving more than 16,000 reports of health risks associated with products containing ephedra.
Reviews of clinical trials revealed hundreds of safety risks associated with ephedra, including high blood pressure, heart attack, stroke, seizure and sudden death. Other side effects of the herb included insomnia, nausea and vomiting.
Finally, in December of 2003, after more than 150 deaths were linked to ephedra-based products, the FDA determined ephedra was not safe for use in weight loss supplements and banned its sale. It was the first time the FDA had banned an herbal weight loss supplement ingredient for safety reasons.
As we’ve noted in other posts, many supplements sold online and in retail stores are made in China and other countries that have low standards for purity and safety. These products may contain harmful contaminants such as pesticide residues and heavy metals. To be safe, choose supplements that are sourced and made entirely within the U.S.
Also, while the FDA does not approve weight loss supplements to affirm their safety and effectiveness, it does offer one type of supplement ingredient regulatory classification: “generally recognized as safe,” commonly referred to as GRAS. An FDA-GRAS designation means an ingredient is generally recognized by qualified experts in the scientific community as safe to consume.
Weight loss supplements are never an easy answer to weight loss. Losing weight and keeping it off require a commitment to eating a healthy diet and getting regular exercise.
If you choose to take a weight loss supplement, you’ll want to take precautions to be safe.
We urge you to speak with your doctor to evaluate the potential benefits and risks of any weight loss supplement. Working together, you and your doctor can find a safe weight loss supplement for you.