A meta-analysis of 10 clinical trials published last year in the European Journal
of Clinical Nutrition found that consuming polyphenol-rich dark chocolate or
cocoa products may reduce total and LDL cholesterol levels (low-density lipoprotein
cholesterol is associated with increased risk of heart disease), but had no effect
on HDL cholesterol levels (high-density lipoproteins supporting protection against
heart disease). The researchers reported that short-term consumption of dark chocolate
reduced total cholesterol by 6.23 mg/dL and LDL was reduced on average by 5.9 mg/dL.
They also noted that the effect appeared to be greater when cocoa polyphenols were
consumed from dark chocolate rather than a cocoa beverage.
Last year, an article in Current Cardiovascular Risk Reports stated that recent
meta-analyses show strong evidence that high-flavonoid cocoa intake lowers
systolic (SBP) and diastolic blood pressure (DBP). One study showed that dark
chocolate (50–70% cacao), compared to cocoa-free controls, or high-flavanol cocoa
compared to low-flavanol cocoa, lowered blood pressure (−3.2 mmHg SBP, −2.0 mmHg DBP).
The results were consistent across dose, quality, duration of trials and population
demographics, thus indicating that the results may have important implications
for public health. In addition, according to another meta-analysis published
in the Archives of Internal Medicine, cocoa consumption reduced hypertension in
an amount equivalent to antihypertensive medications. The researchers at the
University Hospital of Cologne stated that cocoa's hypertensive effects are
clinically noteworthy since similar results are achieved with monotherapy of
beta-blockers or angiotensin-converting enzyme (ACE) inhibitors.
According to a randomized, clinical study published in the Journal of the
American Dietetic Association, overweight and obese women who followed an
energy-restricted dietary pattern that included energy-controlled and
portion-controlled sweet snacks achieved body weight loss over a short-term
period. All participants who followed this reduced-calorie diet and incorporated
a dark chocolate snack or a non-chocolate snack maintained an energy deficit,
lost a significant amount of weight and saw an improvement in body composition.
The researchers stressed the importance of increased education about controlling
sweet snack portions and how they contribute to overall daily energy intake.