Certain compounds in cocoa, called flavanols, may help
sharpen the aging brain. A new
study in Hypertension, an
American Heart Association journal, showed that consuming cocoa flavanols every
day may improve mild cognitive impairment (MCI)—an age-related decline in
memory that sometimes worsens into Alzheimer’s disease.
In the study, 90 older adults with MCI drank a daily
beverage spiked with varying amounts of cocoa flavanols. After eight weeks, those
who consumed higher-flavanol drinks showed improvement on tests of memory, mental
processing speed, and general mental ability. Their overall health improved as
well, shown by drops in blood pressure and insulin resistance.
Past research had found strong evidence for a link between
brain health and flavanol consumption in healthy individuals. “However, our
study is the first to address the relationship between cocoa flavanols and
cognitive function in the context of MCI,” says lead author Giovambattista
Desideri, MD, of the University of L’Aquila in Italy.
Cocoa—the source of chocolate—may affect brain health several
ways. Previous studies suggest that flavanols may increase the number and
strength of connections between brain cells. They may also reduce the loss of
brain cells due to degenerative disease.
Plus, this study suggests that cocoa flavanols may decrease
insulin resistance—the body’s ability to respond to and use the hormone. Insulin resistance is an early step on the path toward type 2 diabetes. There’s
also mounting evidence
for a link between insulin resistance in the brain and the mental decline of Alzheimer’s
disease. Dr. Desideri says, “Alzheimer’s disease is even referred to by some as
type 3 diabetes.”
Cocoa beans are used to make chocolate and powdered cocoa. But
different varieties of cocoa beans contain differing levels of flavanols to
start with. Then they go through various types of roasting and processing
before being made into finished foods. Along the way, they may be combined with
other ingredients, such as whole milk and sugar, which add calories.
Ultimately, the flavanol content and calorie count of chocolate products
can vary widely. The chocolate and cocoa you find on supermarket shelves differs from the drink used in this study as well. “In order to limit calorie intake in the current study, we
used not chocolate, but rather a lower-calorie, nutritionally balanced product
rich in cocoa flavanols,” Dr. Desideri says.
Tips for Chocolate
If you choose to eat chocolate, the National Institutes
of Health (NIH) recommends picking the darkest variety you can find. The
darker the chocolate, the more cocoa solids it contains—and that’s where
researchers think the healthy compounds are found. In contrast, milk chocolate
contains fewer of these solids, and white chocolate contains none at all. If
you drink hot chocolate, the NIH suggests making it with unsweetened cocoa,
water or skim milk, and little added sugar.
Even dark chocolate packs about 155 to 170 calories per ounce, so consume
it sparingly. And, sadly, it’s wise to forgo the
extra calories that come from the fillings in truffles or that dollop of whipped cream on hot chocolate.