There is considerable research showing that nuts, with their high levels of unsaturated fatty acids, fiber and minerals, may help reduce the risk for cardiovascular disease.

But a large Swedish analysis published in Heart has found that the benefits are limited and depend largely on other healthy behaviors.

Researchers followed 61,364 adults for up to 17 years. They had all completed questionnaires on diet, lifestyle and other risk factors for chronic disease.

Nut consumption was associated with lowered risk for heart attack, heart failure, stroke and the irregular rapid heartbeat called atrial fibrillation, or A-fib. But people who routinely consumed nuts were on average younger and more highly educated, had lower body mass index, were more likely to be physically active, less likely to smoke, and more likely to eat fruits and vegetables.

When the researchers controlled for these factors, nut consumption was associated only with a lower risk for A-fib and had no significant effect on the other cardiovascular diseases.

DARK NEWS FOR NIGHT OWLS

Morning people may live longer than night owls, a study suggests.

Researchers studied 433,268 people, ages 38 to 73, who defined themselves as either “definite morning” types, “moderate morning” types, “moderate evening” types or “definite evening” types. They followed their health for an average of 6 1/2 years, tracking cause of death with death certificates. The study is in Chronobiology International.

They found that compared with “definite morning” types, “definite evening” types had a 10 percent increased risk of dying from any cause. Each increase from “morningness” to “eveningness” was associated with an increased risk for disease. Night owls were nearly twice as likely as early risers to have a psychological disorder and 30 percent more likely to have diabetes.

Their risk for respiratory disease was 23 percent higher and for gastrointestinal disease 22 percent higher.

The lead author, Kristen L. Knutson, an associate professor of neurology at Northwestern University, said that while being a night owl was partly genetic, people could make adjustments to sleep time.