Many people with type 2 diabetes are tempted to try dietary supplements to help control the disease, hoping to avoid medication. That’s a risky move, since there’s no convincing evidence that any supplement will help, according to the government’s National Center for Complementary and Integrative Health. Such products often contain a laundry list of herbs, vitamins, minerals, and other compounds.
In recent years the FDA and FTC have cracked down on companies selling products that make explicit or implied medical claims such as “lowers blood sugar naturally,” “can replace medicine in the treatment of diabetes,” and “for relief of diabetic foot pain,” though many persist. Not only do the supplements contain ingredients that are unproven and potentially unsafe, but people taking them may delay getting the medical treatment they really need. For more information from the FDA, go to Beware of Illegally Sold Diabetes Treatments.
Not ready for prime time
That said, the following compounds have shown some promise in research on diabetes. Still, studies have had inconsistent results or have largely been conducted on animals or isolated cells in a lab. And many questions remain about clinical efficacy, dosage, and safety.
Chromium. This essential trace mineral is important in processing carbohydrates and helps cells respond properly to insulin—the hormone that makes blood sugar available to cells. People with type 2 diabetes tend to have lower levels of chromium, so scientists have theorized that supplements of the mineral may help control the disease. But while some small clinical trials have found that chromium (usually the picolinate form) is beneficial, others have not. An analysis of data from seven trials, in the Journal of Pharmacy & Pharmaceutical Sciences in 2013, found that chromium supplements lower fasting blood sugar but do not reduce HbA1c, the best measure of long-term diabetes control. Chromium’s effect may be highly variable because of individual reactions to the mineral. Genetic and ethnic factors may play a role, along with the degree of insulin resistance a person has. For more information, see our general article about chromium supplements.
Ginseng. There are several species of this herb, which vary in their active compounds, so it’s hard to reach general conclusions about its purported benefits for diabetes (or the dozens of other conditions for which it’s promoted). Some small clinical trials have found that certain types of ginseng can help control blood sugar. The Natural Standard, which evaluates herbs and other supplements, has given ginseng a C rating (unclear or conflicting evidence) for people with diabetes. For more general information, see A Reality Check on Ginseng.
Cinnamon. Scientists have isolated substances in cinnamon bark that help control blood sugar in animal studies. But their effect in humans remains unclear. In 2012, researchers for the Cochrane Collaboration looked at 10 clinical trials (generally of poor quality) and concluded that cinnamon is no better than a placebo for the treatment of diabetes. Another analysis, in the Annals of Family Medicine in 2013, also looked at 10 trials (including some that were in the Cochrane review) and concluded that while cinnamon lowers blood sugar, it has no effect on HbA1c. The researchers cautioned that there’s not enough evidence to say who might benefit from cinnamon’s use or what an appropriate dose might be. For more general information, see Sorting Out Cinnamon Claims.
Bottom line: If you have diabetes, work closely with your doctor to control it with a healthy diet, exercise, and medication. Don’t bother with supplements, at least until more is known about their possible benefits and risks.
Also see 5 Foods that Help Fight Diabetes.