The possible association between nut and peanut consumption and mortality rate in both Caucasian and Chinese individuals was examined by Dr. Hung N. Luu from the Vanderbilt University School of Medicine and colleagues. Previous studies had found that the greater the nut consumption, the lower the risk of death from all causes, but that research had primarily been conducted in white, middle to high socioeconomic groups. Dr. Luu and associates extended the evaluation to people of lower socioeconomic status.
The researchers prospectively examined data from three cohorts, including a total of over 200,000 people. Approximately 134,000 were from two cohorts in Shanghai, China, while the rest were from the Southern Community Cohort Study in the southeastern United States, and included both caucasian and African-American participants. The data examined were of all nut and peanut consumption in the US, and of peanut only consumption in the Chinese cohorts.
Follow-up periods ranged from about 5 to 12 years in the three cohorts. When the highest versus lowest nut intake groups were compared, there were 21 and 17 percent decreased risks of death in the US and Chinese cohorts respectively. These differences were statistically significant. Most of these decreased risks were due to decreases in cardiovascular disease. In particular, the risk of death from ischemic heart disease was significantly lower in all ethnic groups included in the study, while the decreased risk from stroke was significant only in the Asian subgroups.
The study authors concluded Consumption of nuts, particularly peanuts given their general affordability, may be considered a cost-effective measure to improve cardiovascular health.
ACSH s Dr. Ruth Kava agreed: Tree nuts and peanuts can certainly be a positive component of a healthy diet. It s important to remember, however, that this type of study cannot determine causality, thus it is always possible that some other aspect of the participants lifestyles might also be responsible for the decreased risk of death. Furthermore, it s unlikely that simply adding nuts and/or peanuts to an otherwise unhealthy diet will bring about such benefits, not to mention the ever-present concern about adding the extra calories that come with over-consumption of nuts.