Medical Compass: Diabetes — Prevention and Reversal

Medical Compass: Diabetes — Prevention and Reversal

Lifestyle modifications, particularly switching to plant-based diets, are effective tools in reversing diabetes.
Antioxidants in foods may reduce diabetes risk

By David Dunaief, M.D.

Type 2 diabetes continues to be an epidemic that is monopolizing health care budgets. According to the Centers for Disease Control and Prevention, the incidence of diabetes has tripled in the last 20 years (1). We need a plan to prevent the disease and to reverse its course.

In medicine, our arsenal of drug therapies has grown considerably, but there are unpleasant side effects. Drugs have even been shown to reduce cardiovascular disease in diabetes patients, which is the number one reason that patients die.

However, there is nothing potentially more powerful with beneficial side effects than lifestyle modifications, especially diet and exercise. And when it comes to reversal, lifestyle modifications are the only potential source.

Two large observational studies, the Adventist Health Study 2 and the EPIC trial, have shown the considerable prevention abilities of diet. In terms of reversal, several studies with a plant-based diet, including one run by Dr. Neal Barnard and another that I published with Dr. Joel Fuhrman, indicate its efficacy. These are backed up by additional anecdotal stories from my clinical experience over an 11-year period.

Let’s look at the research.

Prevention of diabetes with diet

Lifestyle modifications, particularly switching to plant-based diets, are effective tools in reversing diabetes.

A recently published prospective study of the E3N EPIC trial showed considerable benefit from the antioxidant capacity of foods including fruits, vegetables and tea (2). Those who consumed the highest quintile of antioxidants reduced their diabetes risk 39 percent compared to the lowest quintile. After adjusting for weight loss, there was still a statistically significant 27 percent reduction. Interestingly, fruits had the greatest impact with a 23 percent decrease in risk, and vegetables followed with a 19 percent decrease.

This study serves two purposes: one, it shows that antioxidant capacity is important in food; and two, it demonstrates that fruit actually has beneficial effects for those at risk of diabetes. This was not solely a plant-based diet or a vegan or vegetarian diet. This is an impressive effect considering that people may have been eating many other items that may not have been beneficial in addition to fruits and vegetables.

Study participants were 64,223 women who did not have diabetes or cardiovascular disease at the beginning of the study. One of the major weakness of this trial is that the food frequency questionnaire was only used at the study’s start. This means we have to assume people continued to eat the same way throughout the study.

In the Adventist Health Study, the results of a plant-based diet were very powerful. This showed significant effects and, unlike the EPIC trial, compared people who were trying to eat healthy with those who ate either a vegan or vegetarian plant-based diet. Results showed that those who ate a vegan plant-based diet and those who ate a lacto-ovo vegetarian diet were at 62 and 38 percent, respectively, lower risk of developing diabetes than those who were eating a health-conscious omnivore diet (3). This study reaffirms how a plant-based diet is so important when it comes to preventing diabetes.

There were 15,200 men and 26,187 women in this study, and the results were as impressive in both blacks and nonblacks.

Reversal of diabetes with diet

A randomized controlled trial, considered the gold standard of trials, used drug therapy to reduce HbA1C to near nondiabetes levels; however, they could not achieve this before multiple deaths occurred (4). The reason, the researchers surmise, was polypharmacy, or too many drugs.

Fortunately, this is not the case with lifestyle modifications. In one randomized controlled trial, Barnard compared a low-fat vegan diet to the American Diabetes Association diet at the time. The results showed that with a low-fat vegan diet, HbA1C was reduced significantly more than with the ADA diet (5). This trial included 49 patients on the low-fat vegan diet and 50 patients on the ADA diet. The trial duration was 74 weeks. This trial, though small, does show substantial benefit with a low-fat vegan diet.

The benefits of a plant-based diet have been known for many decades. In a 1979 study on diabetes, results showed that insulin was significantly reduced by more than half on a high carbohydrate, high-plant fiber diet (HCF) compared to a control diet (6). This effect was seen in approximately 2.5 weeks.

Involving 20 men with type 2 diabetes who had a mean duration with diabetes of 8 years, patients were started on the control diet for seven days and then switched to the HCF diet for 16 days. This showed reversal with diet over a short period of time and reduction in medication. Thus, diet does not only have an insidious (slow) effect, but it also has an acute (immediate) effect on diseases. Of course, insulin was the gold standard of treatment at the time.

More recently, in a retrospective (backward-looking) case series with 13 men and women with type 2 diabetes, results showed that HbA1C was reduced from a mean of 8.2 to 5.8 percent over a seven-month period (7). This was an impressive 2.4 percent reduction in HbA1C, and 62 percent of patients reached normal sugar levels.

At baseline, patients were on an average of four medications, including diabetes medications. By seven months, they were able to reduce this to one medication while significantly decreasing their HbA1C. In addition, their blood pressure and triglycerides improved. These patients were following a nutrient-dense, plant-based diet. This study was performed by myself and Fuhrman using patients in his practice. The study’s weaknesses were that there was no control arm and that it was retrospective. But this does imply that there is potential for diabetes reversal.

In my clinical practice, I have seen many diabetes patients successfully reverse their disease. Let me share one anecdotal story. A 55-year-old diabetes male Caucasian patient told me that no relative had lived past 57 because they died from diabetes complications. He is currently 60 years old or, as he likes to put it, “three years past expiration date.”

When he first came to see me, he was on four diabetes medications, including insulin, plus a statin. He is no longer on any of these medications. These results were seen in only two months. He did lose weight, but at a much slower pace than the metabolic changes that took place in his body. This anecdotal story is inspirational and reinforces the research above.

In conclusion, while medications are important for the treatment of diabetes, nothing seems to trump lifestyle modifications. Diet, especially, can play both prevention and reversal roles. Even fruit plays a significant role in reducing the incidence of diabetes. Regardless of family history, as demonstrated by my patient, these results can be achieved. Whether or not you are on medications, if you have diabetes, lifestyle modifications should be adopted to get optimal results.

References: (1) (2) Diabetologia online Nov. 9, 2017. (3) Nutr. Metab Cardiovsc Dis. 2013;23(4):292-299. (4) N Engl J Med. 2008;358:2545-2559. (5) Am J Clin Nutr. 2009 May; 89(5): 1588S–1596S. (6) Am J Clin Nutr 1979 32: 2312-2321. (7) Open J Prev Med. 2012 2(3), 364-371.

Dr. Dunaief is a speaker, author and local lifestyle medicine physician focusing on the integration of medicine, nutrition, fitness and stress management. For further information, visit or consult your personal physician.