Eating nuts significantly reduces a person's chances of dying from heart disease or cancer, research has shown.
Scientists found that the more nuts people ate, the less likely they were to die over a period of 30 years.
A daily handful of nuts cut death rates from any cause by a fifth, reduced those related to heart disease by nearly 30%, and lowered the chances of dying from cancer by 11%.
Regular nut-eaters also enjoyed the added benefit of being slimmer than those who avoided nuts.
The findings, drawing on data on almost 120,000 US men and women, suggests that nutty folk who adopt squirrel-like eating habits may be onto something.
"The most obvious benefit was a reduction of 29% in deaths from heart disease - the major killer of people in America," Dr Charles Fuchs, from the Dana-Farber Cancer Institute in Boston, who led the study published in the New England Journal of Medicine, said.
"But we also saw a significant reduction - 11% - in the risk of dying from cancer."
Nut-eaters tend to be more health conscious than average members of the public.
The study found they were leaner, less likely to smoke, and more likely to exercise, take vitamin supplements, and consume fruits and vegetables.
But all these factors were taken into account by the researchers, who used statistica l techniques to isolate the independent association between nut consumption and mortality.
"In all these analyses, the more nuts people ate, the less likely they were to die over the 30-year follow-up period," co-author Dr Ying Bao, from Brigham and Women's Hospital in Boston, said.
All-cause death rates were reduced by 11% in people who ate nuts once a week, 13% in those who ate them two to four times a week, and 15% when nuts were consumed five to six times a week.
Individuals with a daily nut habit were 20% less likely to die over three decades.
The researchers examined health data from two large American lifestyle studies conducted among health workers, the Nurses' Health Study and the Health Professionals' Follow-up Study.
Participants in both filled in detailed food questionnaires every two to four years and the progress of their health was monitored.
As part of the research they were asked to estimate how often they consumed nuts in a serving size of one ounce - equivalent to a handful.
Although the study was unable to single out the "healthiest" nut, it showed that the effect on death rates was similar for "tree nuts", such as walnuts, hazelnuts, cashews, almonds, Brazil nuts, pecans and pistachios, and peanuts, which are not true nuts but beans.
Several previous studies have linked nut consumption with health benefits, such as reducing the risk of heart disease, diabetes and bowel cancer.
But this was the first large scale study of the impact of nut consumption on mortality, the authors said.
The scientists, who received a research grant from the International Tree Nut Council as well as the US National Institutes of Health, said it was not possible to prove a causal link between eating nuts and living longer.
But they wrote: "Our data are consistent with a wealth of existing observational and clinical trial data in supporting the health benefits of nut consumption for many chronic diseases.
"In addition, nutrients in nuts such as unsaturated fatty acids, high-quality protein, fibre, vitamins, minerals, and phytochemicals, may confer cardioprotective, anti-carcinogenic, anti-inflammatory, and antioxidant properties."