Tasty treat found effective in small bites; big candy firms seek permission to sell inferior chocolate
by Craig Weatherby
When it comes to heart health, chocolate has racked up many positive research results, thanks to its unsurpassed bounty of antioxidant polyphenols, of the same type (catechins) found in tea.
But the newest is even more encouraging because it shows that truly minor amounts of the antioxidant-rich confection can lower blood pressure to small but significant extents.
What do blood pressure
Both numbers in a blood pressure reading represent pressure measured as millimeters of mercury (mm Hg).
The higher (systolic) number represents the pressure while the heart contracts to pump blood to the body. The lower (diastolic) number represents the pressure when the heart relaxes between beats.
The systolic pressure is always stated first. For example: 118/76 (118 over 76); systolic = 118, diastolic = 76.
According to the American Heart Association, a blood pressure reading below 120/80 mmHg (millimeters of mercury) is considered optimal for adults.
A systolic pressure of 120 to 139 mmHg or a diastolic pressure of 80 to 89 mmHg is considered "prehypertension" and needs to be watched carefully.
A blood pressure reading of 140 over 90 or higher is considered elevated (high).
Researchers at the University Hospital of Cologne in Germany recruited 44 adults with pre- hypertension (blood pressure ranging from 130/85 to 139/89) or stage one hypertension (blood pressure ranging from 140/90 to 160/100).
Hypertension is defined as having a systolic/diastolic blood pressure reading greater than 140/90, and this common condition kills more than seven million people worldwide every year.
The researchers assigned the volunteers randomly to one of two groups:
- Group 1 ate 6.3 grams (just over one-quarter oz) of dark chocolate—containing 30 calories—daily.
- Group 2 ate the same amount of polyphenol-free white chocolate daily.
At the end of the 18-week study, those who consumed dark chocolate enjoyed smal but clinically significant reductions in systolic and diastolic blood pressure: declines of 2.9 and 1.9 mm Hg (millimeters of mercury) respectively.
And the dark chocolate group showed no changes in body weight, blood fat/cholesterol levels, or blood sugar (glucose) levels.
As the researchers wrote, “Although the magnitude of the blood pressure reduction was small, the effects are clinically noteworthy… it has been estimated that a 3-mm Hg reduction in systolic BP would reduce the relative risk of stroke mortality by eight percent, [risk] of coronary artery disease mortality by five percent, and [risk] of all-cause mortality by four percent” (Taubert D et al 2007).
Affirming the reliability of the results, the blood pressure reductions recorded in this trial approximate those seen in an epidemiological study involving elderly men who ate cocoa habitually.
The rate of hypertension in the dark chocolate group dropped from 86 to 68 percent, indicating that some participants in the dark chocolate group enjyoed reductions above the group average.
The blood pressure reductions in the dark chocolate group were accompanied by a sustained increase in blood levels of S-nitrosoglutathione, which indicates that the benefits stemmed from increased production of vaso-dilating (artery-opening) nitric oxide.
The German team put it this way: “Data in this relatively small sample of otherwise healthy individuals with above-optimal blood pressure indicate that inclusion of small amounts of polyphenol-rich dark chocolate as part of a usual diet efficiently reduced blood pressure and improved formation of vaso-dilative nitric oxide” (Taubert D et al 2007).
Confirming that the polyphenols in the dark chocolate were responsible for the observed benefits, the group that ate polyphenol-free white chocolate showed no changes in blood pressure.
Candy makers seek to cheapen chocolate quality
Major confectioners have asked the Food and Drug Administration let them replace cocoa butter in chocolate with cheaper, possibly less healthful fats and still call the resulting product “chocolate.”
Their motivation is simple: greed. The change would let them to use fewer cocoa beans, thereby saving money, and to sell off the cocoa butter for use in cosmetics, thereby making money.
In 2003, the European Union ruled that companies in member states could substitute five percent of cocoa butter with oils that resemble it chemically, but had to label the products “contains vegetable fats in addition to cocoa butter”. The French call it “cocholat,” a derogatory term derived from their word for pig, “cochon.”
Last year, the Grocery Manufacturers Association added new guidelines for chocolate to a huge petition covering more than 200 foods that would degrade food standards to “permit maximum flexibility in the food technology used to prepare the standardized food” and allow “any alternative process that accomplishes the desired effect.”
This proposal, if accepted by the FDA, would set no limit on how much cocoa butter can be substituted nor restrictions on which fats could be used in place of cocoa butter.
Serious chocolate makers have rallied in opposition, but we wouldn’t bet against the well-connected food giants.
We can only hope that discerning chocoholics will reject the fake, and we pledge never to sell anything but the real thing!
- Taubert D, Roesen R, Lehmann C, Jung N, Schomig E. Effects of low habitual cocoa intake on blood pressure and bioactive nitric oxide: a randomized controlled trial. JAMA. 2007 Jul 4;298(1):49-60.
- Engler MB, Engler MM, Chen CY, Malloy MJ, Browne A, Chiu EY, Kwak HK, Milbury P, Paul SM, Blumberg J, Mietus-Snyder ML. Flavonoid-rich dark chocolate improves endothelial function and increases plasma epicatechin concentrations in healthy adults. J Am Coll Nutr. 2004 Jun;23(3):197-204.