A high intake of fruit and vegetables during early adulthood was associated with a lower risk of having calcified arterial plaque 20 years later, a benefit that was only evident in women, in the CARDIA (Coronary Artery Risk Development in Young Adults) study.
Previous studies have also found that women seem to benefit more from a diet that includes a high intake of fruit and vegetables, a disparity that "should be explored further," said Dr. Michael Miedema, a preventive cardiologist at the Minneapolis Heart Institute. He summarized the results of the study during a webcast held prior to the annual meeting of the American College of Cardiology, where he is presenting the data.
Courtesy National Cancer Institute
A high intake of fruit and vegetables during early adulthood was associated with a lower risk of having calcified arterial plaque 20 years later, a benefit that was only evident in women.
The study evaluated the association between the intake of fruit and vegetables in 2,648 people enrolled in the CARDIA study in 1985 and 1986, at an average age of 25 years, and the presence of coronary artery calcium (CAC), measured with electron-beam computed tomography, 20 years later. Participants were excluded if they consumed less than 800 kcal/day or more than 4,500 kcal/day, or if they had missing CAC scores.
Because there are fewer data in young adults, the study addressed the effect of fruit and vegetable intake during young adulthood on later cardiovascular disease risk. Previous studies have found that a diet high in fruit and vegetables is associated with a lower cardiovascular disease risk in middle-aged adults, with risk decreasing further as intake increases, a finding that has been less consistent in men, Dr. Miedema pointed out.
Fruit and vegetable intake was divided into tertiles, based on the number of servings the study participants reported consuming per day: Women in the top third ate 8-9 servings of fruit and vegetables per day, compared with 3-4 servings a day in the bottom third. The amount consumed was slightly lower in men, at 7-8 servings per day in the top third and 2-3 servings per day in the bottom third. Those in the top third had healthier behaviors, with slightly lower cholesterol and blood pressure levels, and were less likely to smoke.
After adjustment for a 2,000-calorie diet, women who consumed 8-9 servings of fruit and vegetables a day as young adults were about 40% less likely to have calcified plaque in their coronary arteries, compared with women who consumed about 3 servings of fruit and vegetables a day as young adults, Dr. Miedema said. This association was independent of age, weight, race, and lifestyle factors that included smoking, amount of exercise, and alcohol consumption.
Dr. Michael Miedema
"But in men, we did not find the same relationship," he said. Although two previous studies have also suggested that men derive fewer benefits from a diet high in fruit and vegetables, only 1,038 men were enrolled in this study, so it may have been underpowered to detect an effect in men, he added.
The results "reinforce the value of establishing healthy behaviors early in adulthood, and as we talk about population-based approaches to trying to reduce coronary vascular disease, it seems that we should probably include a focus on establishing a high intake of fruits and vegetables early in life," Dr. Miedema concluded
As for the gender difference, the message of the study should not be "that fruit and vegetable intake doesn’t matter in men," but that it is possible that a high intake of fruit and vegetables "doesn’t work quite as well in reducing heart disease risk for men as it does for women," he added. There is no biological explanation for the gender difference, which needs further study, he noted.
The CARDIA study, which is evaluating the development of cardiovascular risk factors and cardiovascular disease in healthy black and white adults, is sponsored by the National Institutes of Health. Dr. Miedema had no disclosures.