A study reported by Duck-Chul Lee in the Journal of American College of Cardiology, 2012 of 3148 men and women over a 6 years period. The study found that there was an increase in high blood pressure by 4% per year, high cholesterol by 3% per year and metabolic syndrome by 2% per year.
Those who gain weight but keep up with fitness level managed to counter the negative effect of weight gain.
It is best if the overweight people can reduce weight and increase fitness at the same time. But this can prove to be difficult for some. So stay fit and active irrespective of your weight if you want to reduce the risk of heart disease.
Healthy but sedentary people can take up moderate exercise such as brisk walking. This applies to overweight and sedentary people but it is better to check with your physician first before starting.
Ultimately, it is critical to maintain or increase in fitness to reduce the risk of heart disease.