Washington, March 3
Eating peanuts may lower your risk of dying from a heart attack, US and Chinese researchers said Monday.
Researchers
at Vanderbilt University and the Shanghai Cancer Institute examined the
association of nut consumption with mortality among low-income and
racially diverse populations and found that intake of peanuts was
associated with fewer deaths, especially from heart disease.
While
research has previously linked nut consumption with lower mortality,
those studies focused mainly on higher-income, white populations. This
study, published in the US journal JAMA Internal Medicine, was the first
to discover that all races -- blacks, whites and Asians alike -- could
potentially increase heart health by eating nuts and peanuts.
"Peanuts
are not nuts but legumes," Xinhua cited senior author Xiao-Ou Shu,
associate director for Global Health at the Vanderbilt-Ingram Cancer
Center (VICC) and professor of Medicine in the Department of
Epidemiology, as saying.
"However, peanuts contain many nutrients
and phytochemicals that are similar to nuts. For individuals who can't
afford tree nuts, peanuts may serve as a substitute," Shu said.
The
results were based on three large ongoing cohort studies. Participants
included more than 70,000 Americans of African and European descent from
the Southern Community Cohort Study (SCCS), who were mostly low-income,
and more than 130,000 Chinese from the Shanghai Women's Health Study
(SWHS) and the Shanghai Men's Health Study (SMHS).
For
participants in the SCCS, deaths were determined by linking with the
National Death Index and Social Security Administration mortality files,
and for participants in the SWHS and SMHS, by linking with the Shanghai
Vital Statistics Registry and by conducting home visits. In total, more
than 14,000 deaths were identified, with a median follow-up of 5.4
years in the SCCS, 6.5 years in the SMHS, and 12.2 years in the SWHS.
They
found a 17-21 percent reduction in total mortality and a 23-38 percent
reduction in cardiovascular mortality for individuals who ate the most
nuts or peanuts compared to those who ate the least nuts or peanuts.
"We
cannot conclude that peanuts per se were responsible for the reduced
mortality observed despite that we have very carefully adjusted for
possible confounders. Randomised clinical trials are needed to establish
a causal connection," Shu said.
However, the data from this new
study reinforced earlier research suggesting health benefits from eating
peanuts and nuts, she noted.
Because peanuts are much less
expensive than tree nuts, as well as more widely available to people of
all races and all socioeconomic backgrounds, Shu said that increasing
peanut consumption may provide a potentially cost-efficient approach to
improving cardiovascular health.
In a related editor's note,
Mitchell Katz, director of the Los Angeles County Department of Health
Services and a deputy editor of JAMA Internal Medicine, wrote: "Of
course, peanuts are not really nuts (they are legumes since they grow in
bushes, unlike tree nuts), but who cares if they help us to live longer
at an affordable price."
Currently, the American Heart
Association recommends eating four 43-gram servings of unsalted, unoiled
nuts a week. However, nutrient-rich nuts are also high in calories, so
don't eat too many if you're watching your weight, the researchers said.
