A large new European study finds that simply eating a lot of fruits and vegetables may not be enough to stave off the weight gain that often comes with age - except for people who recently quit smoking.

Researchers found that of nearly 374,000 adults in 10 European countries, who were followed for five years, those who ate the most fruits and vegetables were no less likely to gain weight once other factors - like calorie intake and exercise habits - were taken into account.

The results, reported in the American Journal of Clinical Nutrition, are not an excuse to skip the fruits and veggies, however.

Plant foods are full of nutrients that may help ward off chronic diseases like heart disease and some cancers, note the researchers, led by Anne-Claire Vergnaud of Imperial College London in the UK.

And in some past studies that assigned overweight people to eat more fruits and vegetables, the diet change has seemed to help.

But the current findings do point to the importance of overall lifestyle in maintaining weight as one ages.