While there have been numerous studies in recent years touting the health benefits of nuts and peanuts, new research published online March 2 in JAMA Internal Medicine (2015; doi:10.1001/jamainternmed.2014.8347) provides a few “firsts.”
Researchers at Vanderbilt University and the Shanghai Cancer Institute followed over 200,000 people from various low-income and racially diverse populations and found that overall mortality during the study was 21% lower, and cardiovascular deaths were 38% less frequent, in those who regularly consumed nuts (about half of which were peanuts) compared with those who did not. Other major studies have linked peanut and nut consumption with lower mortality in higher-income white populations. This is the first study to demonstrate that black, white and Asians from predominantly lower socioeconomic, high-risk groups could benefit from eating nuts, peanuts and peanut butter.
The authors analyzed three large study groups involving 71,764 low-income black and white men and women living in the southeastern United States and 134,265 Chinese men and women living in Shanghai. In both the U.S. and Chinese study groups, men consumed more peanuts than women did. In the U.S. group, about 50% of the nut/peanut consumption came from peanuts, and in the groups from China, only peanut consumption was assessed.
Study results indicated that nut intake was associated with reduced risk of total mortality and cardiovascular disease death in all three groups. In the U.S. study group, total mortality risk was 21% lower for participants who ate the most peanuts. In the Chinese groups, death risk reduction associated with high nut intake was 17% in a combined analysis. An association between high nut intake and reduced risk of ischemic heart disease was seen for all ethnicities.
“We found consistent evidence that high nut/peanut consumption was associated with a reduced risk of total mortality and CVD mortality. This inverse association was observed among both men and women and across each racial/ethnic group and was independent of metabolic conditions, smoking, alcohol consumption and BMI. We observed no significant associations between nut/peanut consumption and risk of death due to cancer and diabetes mellitus. . . . We cannot, however, make etiologic inferences from these observational data, especially with the lack of a clear dose-response trend in many of the analyses. Nevertheless, the findings highlight a substantive public health impact of nut/peanut consumption in lowering CVD mortality given the affordability of peanuts to individuals from all SES [socioeconomic status] backgrounds,” the study concluded.