Astoundingly, even small amounts of dark chocolate polyphenols, 30 mg a day or the amount found in a quarter bar of premium dark chocolate, may protect against high blood pressure, according to an 18-week study published this year in JAMA, the flagship publication of the American Medical Association.8 In individuals with mildly elevated blood pressure (130/85 to 139/89 mmHg), those receiving dark chocolate had a small decrease in average blood pressure, by 2.9 mmHg systolic and 1.9 mmHg diastolic. The percentage of this group classified as hypertensive also decreased from 86% to 68%. The group receiving white chocolate had no significant changes.
Although these blood pressure changes may seem small, they could translate to lower rates of stroke and heart attack and improved survival. When the investigators pooled information from their own and other published studies, they found compelling evidence that cocoa helped lower blood pressure.9 Some studies showed a dose-response effect, with greater improvements accompanying intake of larger amounts of dark chocolate polyphenols.9,10
In a Japanese study, individuals with high cholesterol had improvements in beneficial high-density lipoprotein (HDL), which protects against cardiovascular disease and atherosclerosis, as well as reduction in detrimental LDL when consuming a cocoa drink daily for four weeks.
The most important thing is eat it in moderation and with a very healthy diet rich in fresh fruits, vegetables, berries and omega 3s. berries are most important because most of them especially the red and purple varieties are rich in polyphenols.