Written by Greg Arnold, DC, CSCS. Dark chocolate, because of the high flavanol content in cocoa beans, is significantly superior to white chocolate in decreasing blood pressure and improving fasting blood sugar in study participants with type two diabetes.
According to the American Diabetes Association, in 2012, 29.1 million Americans had diabetes, with 95% of these cases being type 2 diabetes 1. Two of the complications of type 2 diabetes is high blood sugar and high blood pressure, the latter of which costs our healthcare system $46 billion per year 2.
As a result, finding ways to help control blood sugar and maintain a healthy blood pressure is extremely important. Fortunately, research suggests that dark chocolate may be a beneficial food for diabetics. A 2015 study 3 involved 60 subjects (24 men, 36 women) aged 49 to 67 and diagnosed with type 2 diabetes for between 4 and 11 years. They were given either 25 grams of dark chocolate (83% cocoa solids = 32 subjects) or 25 grams of white chocolate (28 subjects) per day for 8 weeks. Before and after the study, blood samples were obtained and weight and blood pressure were measured. The 25 grams of dark chocolate provided 143 calories and 450 milligrams of antioxidants called flavonoids each day.
After 8 weeks, the following results were noted:
| Dark Chocolate | White Chocolate | p-value | |
|---|---|---|---|
| Diastolic BP (mmHg) | 7% decrease (85.15 to 79.21) | 0.2% increase (86.96 to 87.14) | 0.002 |
| Systolic BP (mmgHg) | 4.7% decrease (137.03 to 130.62) | 0.8% decrease (137.32 to 136.25) | 0.004 |
| Fasting blood sugar (mg/dL) | 5.7% decrease (138.06 to 130.21) | 2.9% increase (134.89 to 138.89) | 0.019 |
No significant differences were noted between the groups for weight (p = 0.770), total cholesterol (p = 0.454), HDL cholesterol (p = 0.414), LDL cholesterol (p = 0.340), insulin (p = 0.141), or HbA1C (p = 0.552).
When suggesting how the dark chocolate elicited these benefits, the researchers pointed to studies showing that flavanols, a type of flavonoid present in cocoa beans, have been shown to relax blood vessels 4 by increasing nitric oxide levels in the blood vessels 5. They went on to conclude that “consuming high-polyphenol chocolate improved cardiovascular risk indices by decreasing systolic and diastolic blood pressure in patients with diabetes and hypertension”. Their study highlights “the potential of flavanol-containing diets, and underscores their potential health care benefit for reducing the risk of cardiovascular events in diabetic patients.”
Source: Rostami A. High-cocoa polyphenol-rich chocolate improves blood pressure in patients with diabetes and hypertension. ARYA Atheroscler. 2015 Jan;11(1):21-9.
© 2014 Isfahan Cardiovascular Research Center & Isfahan University of Medical Sciences
Posted November 10, 2016.
Greg Arnold is a Chiropractic Physician practicing in Hauppauge, NY. You can contact Dr. Arnold directly by emailing him at PitchingDoc@msn.com or visiting his web site at www.PitchingDoc.com.
References:
- Association AD. Statistics about diabetes: Overall numbers, diabetes and prediabetes. Retrieved February 2016; 2017. Available at, 15.
- CDC. High Blood Pressure Facts. 2016; Overview of high blood pressure. Available at: https://www.cdc.gov/bloodpressure/facts.htm. Accessed April 26, 2017, 2017.
- Rostami A, Khalili M, Haghighat N, et al. High-cocoa polyphenol-rich chocolate improves blood pressure in patients with diabetes and hypertension. ARYA atherosclerosis. 2015;11(1):21.
- Fisher ND, Hughes M, Gerhard-Herman M, Hollenberg NK. Flavanol-rich cocoa induces nitric-oxide-dependent vasodilation in healthy humans. J Hypertens. 2003;21(12):2281-2286.
- Leikert JF, Rathel TR, Wohlfart P, Cheynier V, Vollmar AM, Dirsch VM. Red wine polyphenols enhance endothelial nitric oxide synthase expression and subsequent nitric oxide release from endothelial cells. Circulation. 2002;106(13):1614-1617.
