First Published Saturday, 21 March 2009
More Reasons to Eat Dark Chocolate
Can eating dark chocolate help lower your blood pressure? Studies reported in the Archives of Internal Medicine and Journal of the American Medical Association suggest the answer is “yes!”
Cocoa-rich dark chocolate may be as good at lowering blood pressure as some medications, according to two studies. But tea — green or black — doesn’t seem to have any significant effect.
A meta-analysis looked at 10 trials that studied the effects of polyphenol-rich tea and cocoa on blood pressure levels. The tea studies revealed no significant effect on blood pressure. But the cocoa studies found that people who ate 50–100 g of dark chocolate a day for two weeks had an average blood pressure decrease of 5/3 mm Hg.
In the second study, cocoa lowered blood pressure in 44 adults with untreated pre-hypertension or mild hypertension who received 6 g a day of dark chocolate or a matching amount of polyphenol-free white chocolate for 18 weeks.
Those eating dark chocolate had an average drop in blood pressure of 3/2 mm Hg, without any change in weight or cholesterol levels. This is one dietary change most people won’t have trouble making.
But beware: Chocolate is high in calories and eating too much can cause weight gain, which could undo cocoa’s blood pressure–lowering effect. So stick with the 6-g dose (0.25 oz) used in the second study; it was nearly as effective and contains only 30 calories.
[These studies were reported in the Archives of Internal Medicine (Volume 167, page 626) and the Journal of the American Medical Association (Volume 298, page 49).]
Another Reason To Go Easy on the Salt Shaker
You know that cutting back on salt is good for your blood pressure, but now there’s evidence it also prevents heart attack and stroke and death from cardiovascular disease.
Blood pressure levels tend to increase with higher intakes of sodium. By limiting your salt intake, you may be able to lower your systolic blood pressure by 2-8 mm Hg.
Salt added to foods during cooking and at the table makes up only about 10% of the sodium consumed in the typical American diet. A much larger proportion of the salt we consume comes from the sodium in processed foods like cold cuts; canned vegetables, meats, and soups; frozen dinners; cheeses; salad dressings; snack foods (such as potato chips); and fast food. Thus, reducing your salt intake means not only avoiding the saltshaker while cooking and at meals, but also reading food labels and choosing foods that are low in sodium.
And now there’s even more reason to go easy on the salt shaker, according to a study reported in the journal BMJ (volume 334, page 885). Researchers followed more than 3,100 adults with prehypertension. Participants who cut their sodium intake were 25% less likely to suffer a cardiovascular event (heart attack, stroke, or need for angioplasty or bypass surgery) or die of cardiovascular disease than those who stuck with their regular, often salt-laden diets. The findings come from two clinical trials that involved men and women 30-54 years old with high-normal blood pressure.
The participants were randomly assigned to either follow their usual diets or learn how to cut salt from their meals; those in the latter group lowered their sodium intake by 25-35%. During the five-year follow-up period, which began 10-15 years after the trials ended, the salt reducers had fewer heart attacks, strokes, and heart procedures, as well as a lower death rate.
Bottom line: These new findings show that the benefits of salt reduction extend beyond lowered blood pressure. So it’s even more important to follow experts’ advice on sodium: no more than 2,300 mg per day, and less than 1,500 mg if you have high blood pressure. Since processed foods are a major sodium source, always read product labels and opt for low-sodium versions whenever possible.