New Orleans, LA, Nov. 8, 2004 -- Young adults who maintain their weight over time, even if they are overweight, have lower risk factor levels for heart disease and are less likely to develop metabolic syndrome in middle age than those whose weight increases, according to the results of a large multi-center study funded by the National Heart, Lung, and Blood Institute of the National Institutes of Health and presented at the annual meeting of the American Heart Association.
Metabolic syndrome is a clustering of risk factors that increases a person's risk of heart disease. After 15 years, only 3.6 percent of the study participants who had maintained their weight had developed metabolic syndrome, compared to 18 percent of those whose weight had increased.
"Young U.S. adults have a major problem with weight gain during these years. The minimum goal for every young adult is to try to prevent weight gain, even if he or she is overweight," said NHLBI Acting Director Barbara Alving, M.D.
The Coronary Artery Risk Development in Young Adults (CARDIA) study followed over 5,000 men and women for 15 years. Selection of study participants who were initially aged 18 to 30 was balanced for sex, race, and education. CARDIA evaluated participants at four clinical centers -- in Birmingham, AL, Chicago, IL, Minneapolis, MN and Oakland, CA. This study included data for 2,475 adults who attended every exam but excluded those who were underweight or very obese at the start of the study.
The study examined the relationship over time between weight and several cardiovascular disease risk factors: high blood pressure, high glucose (sugar) levels which can indicate risk for diabetes, high triglyceride levels, low levels of good cholesterol, and a large waist. Metabolic syndrome is defined as having at least 3 of these risk factors.
Investigators found that on average as body mass index, an indicator of obesity, increased, adverse changes in these cardiovascular disease risk factors occurred. Over the 15 years of the study, these changes produced substantial differences in risk factor levels.
Normal-weight men who maintained their weight had only a 1 mg/dL rise per year in triglycerides (harmful fat in the blood) compared to a 4 mg/dL per year increase in those who had gained weight. After 15 years, that translates into a total increase in triglycerides of 60 versus 15 mg/dL in those who gained compared with those who maintained stable weight. Normal weight women showed almost no increase in triglyceride levels when they maintained their weight, compared to an almost 2 mg/dL rise per year for those whose weight had increased.
Of the adults studied, more than 80 percent had gained weight over the years and had negative changes in heart disease risk factors, compared to 18 percent who had maintained their current weight and showed no significant change in risk factors for heart disease.
"Regardless of whether you are overweight or normal weight in young adulthood, it's really important, at a minimum, not to gain any more weight. That's a critical part of the message," said Donald Lloyd-Jones, M.D., Sc.M. CARDIA investigator and assistant professor of preventive medicine and of medicine at Northwestern University Feinberg School of Medicine. "Weight stabilization may be easier to achieve than significant weight loss for many people, and there are clear benefits to maintaining stable weight," he concluded. Lloyd-Jones presented the results at the AHA's annual conference.
"The best approach for maintaining weight is to ensure that one's physical activity level is high enough to balance the number of calories consumed," said Catherine Loria, Ph.D., a nutritionist and epidemiologist with NHLBI.
To interview Dr. Loria, contact the NHLBI Communications Office at (301) 496-4236 or e-mail email@example.com.To interview Dr. Lloyd-Jones, contact Elizabeth Crown at (312) 503-8928 or at firstname.lastname@example.org.
- Coronary Artery Risk Development in Young Adults (CARDIA) study
- Aim for a Healthy Weight Website: