Shedding the extra pounds will immediately benefit your heart, and it doesn't matter if you exercise more or eat less to fight the flab.
The finding was based on a study, led by Sandor J. Kovacs, Ph.D, M.D., director of the Cardiovascular Biophysics Laboratory and professor of medicine, which analysed a group of healthy, overweight but not obese, middle-aged men and women.
"If individuals want to do something that's good for their heart, then my message to them is lose weight by the method they find most tolerable. They're virtually guaranteed that it will have a salutary effect on their cardiovascular system," Kovacs said.
In the study, the researchers used ultrasound imaging (echocardiography) to measure the diastolic or filling phase of the cardiac cycle because it is a crucial indicator of heart health.
The study participants were non-smokers between ages 50 and 60 and had (Body Mass Indexes) between 23.5 and 30, making them high normal BMIs to overweight.
None of the participants had diabetes, coronary artery disease, stroke, hypertension, cancer or lung disease. Before enrolling in the study, all were relatively sedentary, they exercised less than 20 minutes a day or twice a week.
Twelve participants, including four men and eight women, were in the calorie restriction group, in which volunteers reduced the amount of calories they ate between 12 percent and 15 percent. Their physical activity did not change.
Thirteen participants, including six men and seven women, were in the exercise group and increased their exercise to burn the caloric equivalent of the other group's caloric reduction. The exercise group exercised about six days a week for an hour each session walking, running, cycling or doing elliptical training. Their caloric intake did not change.
At the end of the yearlong study, both the calorie restriction and exercise groups of volunteers lost 12 percent of their weight and 12 percent of their body mass index (BMI), a measurement considered to be a fairly reliable indicator of the amount of body fat.
In both groups, participants' hearts responded to this weight loss by gaining the ability to relax more quickly, recovering some of the elasticity characteristic of younger heart tissue. Those in the calorie restriction group achieved slightly more reduction of heart stiffness.
Kovacs said that he feels the study offers encouragement for those who are overweight.
"One reason that it's hard to get people to change their behaviour and lose weight is that we warn them about consequences of being overweight that might occur sometime in the future — we say if your BMI is too high, eventually you'll develop heart disease, diabetes or hypertension. But now we can tell them, lose weight and right away you can have better cardiovascular health," Kovacs said.
The study is published in the American Journal of Physiology.