Cracking the coconut oil craze
If you Google “coconut oil,”
you’ll see a slew of stories touting the alleged health benefits of this solid
white fat, which is easy to find in supermarkets these days. But how can
something that’s chock-full of saturated fat — a known culprit in raising heart
disease risk — be good for you?
Coconut does have some unique
qualities that enthusiasts cite to explain its alleged health benefits. But the
evidence to support those claims is very thin, says Dr. Qi Sun, assistant
professor in the Department of Nutrition at the Harvard T.H. Chan School of
Public Health.
“If you want to lower your risk
of heart disease, coconut oil is not a good choice,” he says. It’s true that
coconut oil tends to raise beneficial HDL cholesterol more than other fats do,
possibly because coconut oil is rich in lauric acid, a fatty acid that the body
processes slightly differently than it does other saturated fats.
Coconut oil’s effect on cholesterol
But there’s no evidence that
consuming coconut oil can lower the risk of heart disease, according to an
article in the April 2016 Nutrition Reviews. The study, titled
“Coconut Oil Consumption and Cardiovascular Risk Factors in Humans,” reviewed
findings from 21 studies, most of which examined the effects of coconut oil or
coconut products on cholesterol levels. Eight were clinical trials, in which
volunteers consumed different types of fats, including coconut oil, butter, and
unsaturated vegetable oils (such as olive, sunflower, safflower, and corn oil)
for short periods of time. Compared with the unsaturated oils, coconut oil
raised total, HDL, and LDL cholesterol levels, although not as much as butter
did.
These findings jibe with results
from a study by Dr. Sun and colleagues in the Nov. 23, 2016, issue of The
BMJ, which examined the links between different types of saturated fatty
acids and heart disease. Compared with other saturated fats (like palmitic
acid, which is abundant in butter), lauric acid didn’t appear to raise heart
risk quite as much. But that’s likely because American diets typically don’t
include very much lauric acid, so it’s harder to detect any effect, Dr. Sun
notes.
Tropical diets are different
Coconut oil proponents point to
studies of indigenous populations in parts of India, Sri Lanka, the
Philippines, and Polynesia, whose diets include copious amounts of coconut. But
their traditional diets also include more fish, fruits, and vegetables than
typical American diets, so this comparison isn’t valid, says Harvard Medical
School professor Dr. Bruce Bistrian, who is chief of clinical nutrition at Beth
Israel Deaconess Medical Center.
Some of the coconut oil available
in stores is labeled “virgin,” meaning that it’s made by pressing the liquid
from coconut meat and then separating out the oil. It tastes and smells of
coconut, unlike the refined, bleached, and deodorized coconut oil made from the
dried coconut meat used in some processed foods and cosmetics. Virgin coconut
oil contains small amounts of antioxidant compounds that may help curb
inflammation, a harmful process thought to worsen heart disease. But to date,
proof of any possible benefit is limited to small studies in rats and mice,
says Dr. Bistrian.
Unsaturated fats
In contrast, there’s a wealth of
data showing that diets rich in unsaturated fat, especially olive oil, may
lower the risk of cardiovascular disease, Dr. Sun points out. The evidence
comes not only from many observational studies (like those in the
aforementioned BMJreport) but also a landmark clinical trial from
Spain, which found that people who ate a Mediterranean-style diet enhanced with
extra-virgin olive oil or nuts had a lower risk of heart attack, stroke, and
death from heart disease than people who followed a low-fat diet.
Of course, there’s no need to completely
avoid coconut oil if you like the flavor. Some bakers use coconut oil instead
of butter in baked goods, and coconut milk is a key ingredient in Thai cooking
and some Indian curry dishes. Just be sure to consider these foods occasional
treats, not every day fare.