Lowering your calorie intake, without exercise, can help you lose weight and lower your risk of cardiac disease.
We have all heard the mantra that exercise is required to lose weight. There are just as many people that stay the same for lowering you cardiac risk level. We know that abdominal fat or central obesity is a major risk for insulin resistance and diabetes and thus also increases your risk of cardiac disease, but does a loss of abdominal fat also lower your risk no matter what method of weight loss you take.
A new study released in September of 2018 and published in the European Journal of Clinical Nutrition look at this very question. The study, “Exercise training and/or diet on a reduction of intra-abdominal adipose tissue and risk factors for cardiovascular disease”, looked at whether diet and/or exercise that resulted in abdominal weight loss would also result in a reduction in coronary risk levels. Simply, the researchers looked to test the effects of weight loss with and without aerobic and resistance exercise training on the intra-abdominal adipose tissue and risk factors for cardiovascular disease. The coronary risk factors of each participant were evaluated before and after weight loss. The researchers enrolled nearly 125 overweight premenopausal women were randomly assigned to three different groups: diet only (Diet); diet and aerobic training; or diet and resistance training. The researchers implemented the treatment program until a BMI of less than 25 kg/m2 was reached. They used computerized tomography was used to measure intra-abdominal fat levels and blood lipids to measure cardiac risk reduction. Evaluations were made before and after weight loss.
So what did they find? The researchers observed significant reductions of intra-abdominal fat, total cholesterol, low-density lipoprotein cholesterol, triglycerides, and LDL-C/HDL-C. They also found a corresponding increase in high-density lipoprotein following weight loss with and without exercise.
The bottom line: Caloric reduction which leads to significant weight loss will result in a lower cardiac risk with or without exercise. I would argue that the risk reduction appears to tied to a reduction in insulin resistance and central body fat. It would appear that all methods are equally effective for reducing coronary risk factors as long as they reduce abdominal body fat. I am not going to say that exercise is not needed or helpful. It is clear that exercise has a role base don prior research. More studies are needed.