Wine — yes, wine — may have benefits

By David Dunaief, M.D.

Soda has a lot of sugar, with 39 grams per 12-ounce can. Not surprisingly, soda is associated with increased risk of diabetes. However, the drink with the lowest amount of sugar is wine, red or white. Even more surprising, it may have benefits in reducing complications associated with diabetes. Wine has about 1.2 grams of sugar in five ounces. I know what you’re thinking: These different drinks are based on different quantities; however, per ounce, soda has the most and wine has the least.

Why is this important? Well, it wouldn’t be if diabetes were going the way of the dodo bird. Instead, the prevalence of diabetes has continued to climb over three decades in the United States at an alarmingly rapid rate to its current level of 12 to 14 percent (1). The even scarier news is that more than one-third don’t know they have diabetes. The number of patients with prediabetes (HbA1C of 5.7-6.4 percent) is greater than one in three in this country.

So where do we stand? Only recently did the United States Preventive Services Task Force (USPSTF) and the American Diabetes Association (ADA) converge on screening guidelines. However, originally, the USPSTF recommended that asymptomatic patients not be screened for diabetes since the evidence is inconclusive and screening may not improve mortality. Now they give the evidence a grade of B, which means there is a moderate amount of evidence, not even a grade of A. ADA guidelines suggest testing those who are overweight and who have one or more risk factors for diabetes and all of those who are over 45 (2, 3).

It turns out that, for those with diabetes, cardiovascular risk and severity may not be equal between the sexes. In two trials, women had greater risk than men. In one study, women with diabetes were hospitalized due to heart attacks at a more significant rate than men, though both had substantial increases in risk, 162 percent and 96 percent, respectively (4). This was a retrospective (backward-looking) study. The same result was found in a second study (5). In this meta-analysis (a group of 19 studies), there was a 38 percent greater increased risk of cardiovascular events in women than men. The latter was presented as a poster, not fully published data.

What may reduce risks of disease and/or complications? Fortunately, we are not without options. Several factors may help. These include timing of blood pressure medications, lifestyle modifications (diet and exercise) and wine.

Diet trumps popular drug for prevention

All too often in the medical community, we are guilty of reaching for drugs and either overlooking lifestyle modifications or expecting that patients will fail with them. This is not only disappointing, but it is a disservice; lifestyle changes may be more effective in preventing this disease. In a head-to-head comparison study (Diabetes Prevention Program), diet plus exercise bests metformin for diabetes prevention (7). This study was performed over 15 years of duration in 2,776 participants who were at high risk for diabetes because they were overweight or obese and had elevated sugars.

There were three groups in the study: those receiving a low-fat, low-calorie diet with 15 minutes of moderate cardiovascular exercise; those taking metformin 875 mg twice a day; and a placebo group. Diet and exercise reduced the risk of diabetes by 27 percent, while metformin reduced it by 18 percent over the placebo, both reaching statistical significance. While these are impressive results that speak to the use of lifestyle modification and to metformin, this is not the optimal diabetes diet.

Wine is beneficial, really?

Alcohol in general has mixed results. Wine is no exception. However, the CASCADE trial, a randomized controlled trial, considered the gold standard of studies, shows wine may have heart benefits in well-controlled patients with type 2 diabetes by altering the lipid (cholesterol) profile (6).

Patients were randomized into three groups, each receiving a drink with dinner nightly; one group received five ounces of red wine, another five ounces of white wine, and the control group drank five ounces of water. Those who drank the red wine saw a significant increase in their “good cholesterol” HDL levels, an increase in apolipoprotein A1 (the primary component in HDL) and a decrease in the ratio of total cholesterol-to-HDL levels compared to the water drinking control arm. In other words, there were significant beneficial cardiometabolic changes.

White wine also had beneficial cardiometabolic effects, but not as great as red wine. However, white wine did improve glycemic (sugar) control significantly compared to water, whereas red wine did not. Also, slow metabolizers of alcohol in a combined red and white wine group analysis had better glycemic control than those who drank water. This study had a two-year duration and involved 224 patients. All participants were instructed on how to follow a Mediterranean-type diet.

Does this mean diabetes patients should start drinking wine? Not necessarily, because this is a small, though well-designed, study. Wine does have calories, and these were also well-controlled type 2 diabetes patients who generally were nondrinkers.

Drugs — not diabetes drugs — show good results

In the May 11, 2017 column I wrote that taking blood pressure medications at night may control blood pressure better than only taking these medications in the morning. Well, it turns out this study also shows that taking blood pressure medications has another benefit, lowering the risk of diabetes (8). There was a 57 percent reduction in the risk of developing diabetes in those who took blood pressure medications at night rather than in the morning.

It seems that controlling sleep-time blood pressure is more predictive of risk for diabetes than morning or 48-hour ambulatory blood pressure monitoring. This study had a long duration of almost six years with about 2,000 participants.

The blood pressure medications used in the trial were ACE inhibitors, angiotensin receptor blockers and beta blockers. The first two medications have their effect on the renin-angiotensin-aldosterone system (RAAS) of the kidneys. According to the researchers, the drugs that blocked RAAS in the kidneys had the most powerful effect on preventing diabetes. Furthermore, when sleep systolic (top number) blood pressure was elevated one standard deviation above the mean, there was a 30 percent increased risk of type 2 diabetes. Interestingly, the RAAS blocking drugs are the same drugs that protect kidney function when patients have diabetes.

We need to reverse the trend toward higher diabetes prevalence. Diet and exercise are the first line for prevention. Even a nonideal diet, in comparison to medication, had better results, though medication such as metformin could be used in high-risk patients that were having trouble following the diet. A modest amount of wine, especially red, may have effects that reduce cardiovascular risk. Blood pressure medications taken at night, especially those that block RAAS in the kidneys, may help significantly to prevent diabetes.

References: (1) JAMA 2015;314(10):1021-1029. (2) uspreventiveservicestaskforce.org. (3) Diabetes Care 2015;38(Suppl. 1): S1–S94. (4) Journal of Diabetes and Its Complications 2015;29(5):713-717. (5) EASD 2015; Poster #269. (6) Ann Intern Med. 2015;163(8):569-579. (7) Lancet Diabetes Endocrinol. Online Sept. 11, 2015. (8) Diabetologia. Online Sept. 23, 2015.

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 www.medicalcompassmd.com or consult your personal physician.