News Release

Health benefits of leanness blown away by cigarette smoke

American Heart Association meeting report

Peer-Reviewed Publication

American Heart Association

HONOLULU, April 25 – Although smokers tended to be leaner than nonsmokers overall, their tobacco use negated the heart-protective benefits usually associated with low-body fat, according to an analysis of 23 studies. The findings, presented today at the American Heart Association’s Asia Pacific Scientific Forum, held across race, gender, national origin and ethnicity. “There is a public perception that smoking has a health benefit in that it keeps people thinner. That perception is dead wrong,” says Daniel T. Lackland, Dr.P.H., professor of epidemiology at the Medical University of South Carolina in Charleston.

“In our analysis, the risk of death faced by smokers from heart attack and other causes was very high. The benefit of thinness was negligible by comparison. These results were fairly consistent across national, ethnic and racial lines,” he says.

Overall, men who smoked cigarettes had a 50 percent greater relative risk of dying from a heart attack compared to nonsmoking men. The numbers were even more dramatic for female cigarette smokers – they had an 80 percent greater relative risk of dying from a heart attack compared to their nonsmoking peers. Female smokers also had a higher risk of dying from other causes.

Female smokers tended to be both leaner than their cigarette-using male counterparts as well as having a higher risk of heart attack death. According to Lackland, this gender difference was unexpected, and requires further research. “We have known for some time that smokers of both genders tend to be leaner, and leanness is cardio-protective,” says Lackland. “We looked at 59 analytic groups within the 23 studies from around the world to examine whether weight control through smoking had any health benefits whatsoever as a means to reduce the risk of heart attack, or death from other causes,” he says. The researchers examined data from more than 250,000 men and women of diverse ethnic and racial groups from Asia, Europe and the United States as part of the Diverse Populations Collaboration, which is funded by the National Heart, Lung, and Blood Institute and the National Institute of Diabetes and Digestive and Kidney Diseases. The studies were conducted from 1960 to the mid 1990s. Although the weights of the individuals varied greatly by region. On average, nonsmoking males were about 5 pounds heavier than the smokers, and nonsmoking females were about 7 ½ pounds heavier than their cigarette-smoking peers.

According to the American Heart Association, smoking increases the risk of heart attack. When it is combined with other risk factors – such as high blood pressure, high cholesterol level, obesity, diabetes and a sedentary lifestyle, the risk rises exponentially.

Exactly how smoking increases the risk of heart attack is not fully understood. However, scientists do know that the ratio of high-density lipoprotein cholesterol (the “good” cholesterol) to low-density lipoprotein cholesterol (the “bad” cholesterol) tends to be lower in smokers compared to nonsmoker. This puts smokers at higher risk of developing atherosclerosis, the disease process that underlies heart attacks and strokes.

The arteries of smokers tend to be stiffer, and have more plaque, the waxy buildup of cholesterol and other elements that can “clog” the arteries. Because the diseased arteries lack elasticity, they are less likely to “give” when stressed, and the hard plaque inside is more likely to rupture and create a clot that can cause a heart attack. The reason that smokers tend to be thinner is also not well understood. Scientists propose that chemicals in tobacco suppress appetite, making a person eat smaller portions of food and take in fewer calories.

The American Heart Association recommends balancing the number of calories consumed with the amount of calories burned through physical activity and basic metabolic function to achieve and maintain a healthy body weight. A healthy diet should emphasize whole grains, low-fat dairy products, lean meats, poultry, fish, fruits and vegetables.

###

Co-authors are Youlian Liao, M.D.; Guichan Cao, M.S.; and Daniel L. McGee, Ph.D., Medical University of South Carolina, Charleston, S.C.

CONTACT:
Darcy Spitz or Carole Bullock
AHA News Media Relations
Hawaii Convention Center
Honolulu, Hawaii
Ph. (808) 792-6515

Abstract #P322


Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.