Understanding safety concerns
Limited research also makes it difficult to judge the safety of a weight-loss supplement. And a product isn't necessarily safe simply because it's natural.
Ephedra, or ma huang, is an herbal stimulant that was once used in weight-loss products. In 2004, the FDA banned ephedra because of possible adverse effects, including mood changes, hypertension, irregular heart rate, stroke, seizures and heart attacks.
Bitter orange is a currently available herbal stimulant that is often called an "ephedra substitute" and is used in some weight-loss supplements. The active ingredient in bitter orange has chemical properties and actions that are similar to ephedra and may be associated with similar adverse effects. Because of limited research and the use of bitter orange in multi-ingredient supplements, the safety of the product isn't well-understood.
Researching before you buy
It's important to do your homework if you're thinking about trying over-the-counter weight-loss pills. General information about many dietary supplements is available at the website of the National Center for Complementary and Alternative Medicines.
The Natural Medicines Comprehensive Database summarizes research regarding dietary supplements and herbal products. Although the database is only available by subscription, you may be able to access it through a public library.
The following table shows common weight-loss pills and what the research shows about their effectiveness and safety.
|SOURCES: JAMA, 2014; GLAXOSMITHKLINE CONSUMER HEALTHCARE, 2014; NATIONAL INSTITUTES OF HEALTH OFFICE OF DIETARY SUPPLEMENTS, 2014; NATURAL MEDICINES COMPREHENSIVE DATABASE, 2014; GASTROENTEROLOGY RESEARCH AND PRACTICE, 2011; JOURNAL OF THE INTERNATIONAL SOCIETY OF SPORTS NUTRITION, 2013.
|Alli — nonprescription version of orlistat
||Decreases absorption of dietary fat
||Modest benefit, less effective than prescription-strength orlistat (Xenical)
||Loose stools, oily spotting, frequent or hard-to-control bowel movements; reports of rare but serious liver damage
|Bitter orange (Citrus aurantium)
||Increases calories burned, suppresses appetite
||Possible modest benefit; very little data
||Increased heart rate and blood pressure; reports of anxiety, stroke, irregular heartbeat, heart attack
|Chitosan (from exoskeleton of shellfish)
||Blocks absorption of dietary fat
||Probably ineffective; few well-designed studies
||Uncommon: upset stomach, nausea, gas, increased stool bulk, constipation
|Chromium (essential mineral)
||Increases lean muscle mass, decreases appetite, increases calories burned
||Uncommon: watery stools, headache, weakness, insomnia, nausea, vomiting, constipation, dizziness, hives
|Conjugated linoleic acid (derived from dairy products and beef)
||Reduces body fat
||Possible modest benefit
||Upset stomach, nausea, constipation, loose stools; may decrease good cholesterol and increase bad cholesterol
|Green coffee extract
||Reduces absorption of sugar (glucose), increases calorie and fat metabolism
||Possible modest benefit
||Excessive use: anxiety, agitation, insomnia, nausea, irregular heartbeat
|Green tea extract
||Decreases fat absorption, increases calorie and fat metabolism
||Possible slight benefit
||Long-term use with high doses: insomnia, agitation, dizzinesss, nausea, vomiting, bloating, gas, diarrhea; reports of liver damage
|Guar gum (derived from Indian cluster bean)
||Blocks absorption of dietary fat, increases feeling of fullness
||Abdominal pain, gas, diarrhea
|Hoodia (succulent plant)
||Probably ineffective; insufficient data
||Headache, dizziness, nausea, vomiting; possible increase in heart rate and blood pressure
||Increases fat metabolism
Including your doctor in your weight-loss plans
If you're considering weight-loss pills, be sure to talk with your doctor, especially if you have health problems, take prescription drugs, or are pregnant or breast-feeding. It's important to get advice on possible interactions with your current use of medicine, vitamins or minerals.
Your doctor can offer advice on losing weight, provide support, monitor your progress or refer you to a dietitian.
Dec. 19, 2014
See more In-depth
- Dietary supplements for weight loss. National Institutes of Health Office of Dietary Supplements. http://ods.od.nih.gov/factsheets/WeightLoss-HealthProfessional/. Accessed Nov. 13, 2014.
- Hensrud DD (expert opinion). Mayo Clinic, Rochester, Minn. Nov. 28, 2014.
- Yanovski SZ, et al. Long-term drug treatment for obesity: A systematic and clinical review. JAMA. 2014;311:74.
- Lopez HL, et al. Eight weeks of supplementation with a multi-ingredient weight loss product enhances body composition, reduces hip and waist girth, and increases energy levels in overweight men and women. Journal of the International Society of Sports Nutrition. 2013;10:22.
- Bitter orange. Natural Medicines Comprehensive Database. http://www.naturaldatabase.com. Accessed Nov. 23, 2014.
- Alli. GlaxoSmithKline Consumer Healthcare, L.P. http://www.accessdata.fda.gov/drugsatfda_docs/label/2014/021887Orig1s006lbl.pdf. Accessed Nov. 26, 2014.
- Bitter orange. National Center for Complementary and Alternative Medicine. http://nccam.nih.gov/sites/nccam.nih.gov/files/Herbs_At_A_Glance_Bitter_Orange_06-13-2012_1.pdf. Accessed Nov. 26, 2014.
- Chitosan. Natural Medicines Comprehensive Database. http://www.naturaldatabase.com. Accessed Nov. 23, 2014.
- Chromium. Natural Medicines Comprehensive Database. http://www.naturaldatabase.com. Accessed Nov. 23, 2014.
- Conjugated linoleic acid. Natural Medicines Comprehensive Database. http://www.naturaldatabase.com. Accessed Nov. 23, 2014.
- Onakpoya I, et al. The use of green coffee extract as a weight loss supplement: A systematic review and meta-analysis of randomised clinical trials. Gastroenterology Research and Practice. 2011:382852.
- Green coffee extract. Natural Medicines Comprehensive Database. http://www.naturaldatabase.com. Accessed Nov. 23, 2014.
- Green tea extract. Natural Medicines Comprehensive Database. http://www.naturaldatabase.com. Accessed Nov. 23, 2014.
- Guar gum. Natural Medicines Comprehensive Database. http://www.naturaldatabase.com. Accessed Nov. 23, 2014.
- Hoodia. Natural Medicines Comprehensive Database. http://www.naturaldatabase.com. Accessed Nov. 23, 2014.