Good news for nut producers – and consumers: the findings the largest study of its kind suggest that eating walnuts, other tree nuts and/or peanuts regularly can protect significantly against the development of cardiovascular and coronary heart diseases.
Analysis of pooled data from more than 210,000 respondents across a trio of longitudinal studies indicated that those who ate five or more servings of nuts a week had a 14 percent lower risk of developing cardiovascular disease (CVD) and a 20 percent lower risk of developing coronary heart disease (CHD), compared to those who reported eating no nuts, or nearly no nuts.
The study, published in the November 2017 issue of the Journal of the American College of Cardiology, adds considerable weight to the growing body of scientific research backing the health benefits of nut consumption.
According to Marta Guasch-Ferré, PhD, a research fellow in the department of nutrition at Harvard T.H. Chan School of Public Health and lead author of the study, “Our findings support recommendations of increasing the intake of a variety of nuts, as part of healthy dietary patterns, to reduce the risk of chronic disease in the general population”.
Methodology and key findings
Dr Guasch-Ferré and her team analysed data from a trio of large-scale surveys to ascertain the potential benefits of eating nuts – walnuts, other tree nuts, the nut-like legume, peanuts, and peanut butter – with regard to a person’s risk of developing cardiovascular problems and associated health events.
Peanut and peanut butter consumption were included in the analysis because their fatty acid and nutrient profile is similar to those of tree nuts.
They ascertained respondents’ nut consumption using the ‘food frequency questionnaires’, conducted at the beginning of each of the studies and updated every four years.
In all, there were 14,136 documented cases of cardiovascular disease (CVD), including 8,390 cases of coronary heart disease (CHD) and 5,910 of stroke.
Some number-crunching revealed that consuming a serving of walnuts one or more times a week was linked with a 19 percent lower risk of developing CVD and a 21 percent lower risk of developing CHD in the ensuing years.
Peanuts or tree nuts were less potent in their effects but upping consumption brought their benefits closer to those of walnuts, the researchers found, particularly when it came to tree nuts and coronary heart disease.
Those respondents who reported eating peanuts or tree nuts twice or more weekly cut their risk of developing CVD and CHD by 13 percent and 15 percent, respectively; and their risk of developing CHD by 15 percent and an impressive 23 percent, respectively, compared to those who never or nearly never ate nuts.
The researchers found no significant links between regular consumption of all nuts, or peanut butter, or tree nuts, and a person’s risk of stroke; they did observe, however, that eating peanuts and/or walnuts appeared to have a protective effect against stroke.
Further research directions
In an accompanying editorial comment, Emilio Ros, MD, PhD, of the Endocrinology and Nutrition service at Barcelona’s Hospital Clínic and an investigator with CIBEROBN, a research network attached to Spain's Instituto de Salud Carlos III, noted that while the study’s consistent findings strongly suggest a link between nut consumption and heart-disease protection, more research is needed.
“Ideally, further investigations should test the effects of long-term consumption of nuts supplemented into the usual diet on hard cardiometabolic events,” Ros advised.
“In the meantime, raw nuts, if possible unpeeled and otherwise unprocessed, may be considered as natural health capsules that can be easily incorporated into any heart-protective diet to further cardiovascular well-being and promote healthy aging.”
Source: Food Navigator