A La Carte: Dietary Supplements and Diabetes

An estimated one-third of all diabetes patients are using some form of alternative medicines. Whether this is a passing fad or the wave of the future remains to be seen, but the impacts of these therapies are still largely unknown and more studies are needed.

The estimated number of adults with diabetes who use some type of complementary and alternative medicine (CAM) now hovers at more than 33%. An evergrowing population of diabetes patients is turning to dietary supplements, herbs, and mind-body medicine to improve the outcomes of their disease and for overall good health. The trend has made fielding patients’ questions about dietary supplements a common part of the day for today’s physicians.

Brent A. Bauer, MD, director of the Complementary and Integrative Medicine Program at the Mayo Clinic, says he faces these questions almost every day — mostly centered on what are the risks and benefits of products such as cinnamon and chromium for managing diabetes.

“I always ‘back the train up’ and spend time reviewing with the patient what they are doing from a lifestyle approach first,” Bauer says. “We want to make sure they have optimized health and wellness promoting activities within each of the four key domains that have been associated with optimizing health, even at the genetic level.”

“These [domains] include nutrition, mostly a wholefoods, largely plant-based approach; daily exercise; daily practice of a formal stress management program; and maintenance of a formal support network,” Bauer continues. “Only if we have paid full attention to each of these areas, and optimized our wellness activities within each, should we consider the possible role of a supplement.”

Bauer says once that solid foundation is in place, he helps patients explore targeted, evidence-based use of a particular supplement, individualized for that specific patient’s overall condition.

While physicians, such as Bauer, in the CAM specialty may have regular dialogues with their patients on the topic, a 2010 study in Clinical Diabetes reported that at least 63% of the general population does not disclose use of CAM therapies to their physicians.

Bauer says, however, he thinks most physicians recognize that CAM is now part of the U.S. healthcare approach.

“Increasingly, we recognize that not asking about CAM use only ensures that the patient will obtain their information somewhere else, such as a doctor on a TV show, a friend, or an Internet ad,” Bauer says. “Much better for us to be directly involved in helping make sure they have solid information so that they can make an evidence-based and informed decision about the use, or not, of any supplement.”

And while the National Center for Complementary and Alternative Medicine believes there is not enough scientific evidence to show any dietary supplements can help prevent or manage diabetes, some studies have yielded positive results. Here, we take a look at some of the latest research dindings of the most common dietary supplements used to treat the disease:

A 2014 systematic review in the Journal of Clinical Pharmacy and Therapeutics of 25 randomized controlled trials concluded that evidence suggests daily doses of more than 200 µg chromium monosupplementation has favorable effects on glycemic control in patients with diabetes. Chromium monotherapy also signifi cantly reduced triglycerides and increased HDL-C levels. The improvements on glucose and triglycerides levels were evident especially with chromium picolinate. At usual doses, the supplement did not increase the risk of adverse events compared with placebo. Still, long-term benefi t and safety remain to be further investigated.

Alpha-lipoic acid
As an antioxidant, alpha-lipoic acid (ALA) has been studied for its ability to decrease high levels of oxidative stress, which contributes to high blood glucose in diabetes patients as well as other secondary complications. In a 2011 clinical trial of 102 diabetes patients, published in Diabetes Research and Clinical Practice, daily supplements of 600 mg ALA and 800 mg vitamin E supplements (alpha-tocopherol) taken together or separately for four months did not improve cholesterol levels or insulin responses.

A recent review in Nutrition Journal evaluated the available evidence of five herbs gaining popular use worldwide, including cinnamon, bitter gourd, and fenugreek. The review cautions, “herbal medicines constitute many hundreds to thousands of active and inactive ingredients, the effects of which are not known when used outside the plants’ natural use. Many trials have used large doses of naturally occurring substances, which would be many times the ordinary intake.”

Lead author Arjuna Medagama, MD, of the University of Peradeniya in Sri Lanka, tells Endocrine News most of the complementary medicines in use today have their roots in Asia.

“Most substances like cinnamon and bitter gourd rather than being prescribed as medicines are consumed as everyday accompaniments at their daily meal,” he says. “As such, the amount of active ingredients ingested are limited compared to the concentrated extracts that have been used in trials.”

“This point has not been widely acknowledged, and the trials we see today are too short and the participants are few,” Medagama adds. “Therefore, caution needs to be exerted when complementary medicines are advocated.”

Medagama says despite the fact that the evidence base for most substances are limited, cinnamon happens to be widely studied and seems to be effective when used alone in mild diabetes and in patients who have poor initial glycemic control.

“Bitter gourd, too, seems to show promise, but further research is required regarding the type of preparation that is effective. The available evidence seems to favor raw bitter gourd juice,” he advises.

In another analysis, a 2013 systemic review in the Annals of Family Medicine evaluated 10 randomized controlled studies of 543 type 2 diabetes patients who consumed daily cinnamon doses of 120 mg to 6 g for four to 18 weeks. The patients had reduced levels of fasting blood glucose, total cholesterol, and triglycerides. Cinnamon also increased levels of HDL-C. It did not, however, have any effect on hemoglobin A1C levels.

The Chinese herb known as Tianqi was found to reduce the progression of prediabetes to type 2 diabetes by almost a third (32.1%) in a recent study in the Journal of Clinical Endocrinology & Metabolism. Tianqi is a combination of 10 Chinese medicinal herbs in a capsule, with the key herb reported as Huanglian (Coptidis Rhizoma). The researchers from the University of Chicago reported that in its randomized trial of 420 patients with impaired glucose tolerance, those who received Tianqi over 12 months compared to those in the placebo group had a signifi cantly decreased incidence of type 2 diabetes — and the herbal drug was found safe to use.

Clinical trials have not proven that magnesium supplements help manage type 2 diabetes symptoms. According to a large 2007 analysis, however, people who had a diet rich in magnesium from foods (whole grains, nuts, and green leafy vegetables) and supplements had a 15% reduced risk of developing the disease.

Omega-3 Fatty Acids
As one of the most common dietary supplements taken in the U.S., omega-3s have been found useful in reducing the risk of heart disease and decreasing triglyceride levels. A 2008 systematic review, however, of 23 trials reported omega-3 fatty acids had no signifi cant changes in fasting glucose, A1C, or fasting insulin in patients with type 2 diabetes.

More to Come

As researchers around the globe continue to explore the
possibilities of dietary supplement use for treating diabetes,
patients are awaiting news of promising results.
Currently, dozens of clinical trials are recruiting diabetes
patients of different ages, disease states, and races — all
aiming to provide solid scientific evidence of the effectiveness
of alternative medicine.

You may also like

  • Insulin Titration Software Combined with CGM Enables Patients with Diabetes to Improve Time in Range

    First study to utilize CGM data with FDA-cleared, cloud-based titration software suggests significantly improved outcomes for patients while optimizing clinical resources This past summer, Glytec published the first proof-of-concept study that combines FDA-cleared remote insulin titration software and data from continuous glucose monitoring (CGM) systems. Results of the study, presented at the American Diabetes Association’s…

  • Positive Topline Results Announced in Type 1 Diabetes Clinical Trial

    A clinical trial investigating a possible novel treatment of early-onset type 1 diabetes last month met the primary endpoint assessing the safety and tolerability of a new class of microbe-based therapeutic agents. Precigen ActoBio is evaluating this therapy — AG019 ActoBiotics — as a monotherapy and in combination with teplizumab. AG019 is formulated as an…