Maastricht: Nuts and peanuts, but not peanut butter, may protect against death from cancer, heart disease, respiratory disease and other major causes, new study finds. A paper published today in the International Journal of Epidemiology confirms a link between peanut and nut intake and lower mortality rates, but finds no protective effect for peanut butter. Men and women who eat at least 10 grams of nuts or peanuts per day have a lower risk of dying from several major causes of death than people who don't consume nuts or peanuts. The reduction in mortality was strongest for respiratory disease, neurodegenerative disease and diabetes, followed by cancer and cardiovascular diseases. The effects are equal in men and women. Peanuts show at least as strong reductions in mortality as tree nuts, but peanut butter is not associated with mortality, researchers from Maastricht University found.
This study was carried out
within the Netherlands Cohort Study, a study running since 1986 among
over 120,000 Dutch men and women 55-69 year old. Nut consumption was
assessed by asking about portion size and frequency of intake of
peanuts, other nuts (tree nuts) and peanut butter. The researchers from
Maastricht University analyzed the relationship with overall and
cause-specific mortality since 1986.
The associations between
nuts and peanuts intake and cardiovascular death confirm earlier results
from American and Asian studies that were often focused on
cardiovascular diseases. However, in this new study, it was found that
mortality due to cancer, diabetes, respiratory and neurodegenerative
diseases was also lowered among users of peanuts and nuts. Project
leader and epidemiologist Professor Piet van den Brandt commented: “It
was remarkable that substantially lower mortality was already observed
at consumption levels of 15 grams of nuts or peanuts on average per day
(half a handful). A higher intake was not associated with further
reduction in mortality risk. This was also supported by a meta-analysis
of previously published studies together with the Netherlands Cohort
Study, in which cancer and respiratory mortality showed this same
Peanuts and tree nuts both contain
various compounds such as monounsaturated and polyunsaturated fatty
acids, various vitamins, fiber, antioxidants, and other bioactive
compounds, that possibly contribute to the lower death rates. In
contrast to peanuts, no association was found between peanut butter
intake and mortality risk. However, besides peanuts, peanut butter
contains also added components like salt and vegetable oils. In the
past, it has been shown that peanut butter contains trans fatty acids.
The composition of peanut butter is therefore different from peanuts.
The adverse health effects of salt and trans fatty acids could inhibit
the protective effects of peanuts.