Being fat tied to poor heart health, despite regular exercise

People who are overweight or obese are at a higher cardiovascular risk compared with their peers with normal weight, even in people who exercise, a study shows — highlighting that exercise does not negate the harms of excess body weight on cardiovascular health.

“One cannot be ‘fat but healthy’,” said principal investigator Dr.Alejandro Lucia from the European University in Madrid, Spain.

Previously, there have been suggestions that being “fat but fit” was associated with similar cardiovascular risk as being “thin but unfit”, according to Lucia. “This has led to controversial proposals for health policies to prioritise physical activity and fitness above weight loss. Our study sought to clarify the links between activity, body weight, and heart health.”

Analysing a large cohort of 527,662 participants (mean age 42.3 years, 32 percent female) stratified based on their BMI, the researchers found that those who engaged in any levels of physical activity had a lower risk of having high blood pressure, high cholesterol, or diabetes than those with no exercise at all — and this benefit was seen across all BMI categories. [Eur J Prev Cardiol 2021;doi:10.1093/eurjpc/zwaa151] 

Furthermore, with increasing levels of physical activity, the risk of having high blood pressure or diabetes decreased more compared with no exercise, regardless of sex and BMI categories. 

“This tells us that everyone, irrespective of their body weight, should be physically active to safeguard their health,” said Lucia. “More activity is better, so walking 30 minutes per day is better than walking 15 minutes a day.”

However, for obese individuals, the risk of having hypertension (odds ratios [ORs], 4.93 vs 1.25 in men; 5.45 vs 1.30 in women), diabetes (ORs, 3.62 vs 1.56 in men; 4.18 vs 1.27 in women), and high cholesterol levels (ORs, 2.03 vs 1.16 in men; 1.36 vs 1.05 in women) remained greater despite being physically active compared with normal weight individuals who were sedentary.

Similar results were seen in overweight individuals, whom despite being active, were at greater risk of having hypertension (ORs, 1.98 vs 1.25 in men; 2.46 vs 1.30 in women) and high cholesterol levels (ORs, 1.61 vs 1.16 in men; 1.41 vs 1.05 in women) than inactive individuals of normal weight.

“Exercise does not seem to compensate for the negative effects of excess weight. This finding was also observed overall in both men and women when they were analysed separately,” noted Lucia.

“This was the first nationwide analysis to show that being regularly active is not likely to eliminate the detrimental health effects of excess body fat. Our findings refute the notion that a physically active lifestyle can completely negate the deleterious effects of overweight and obesity,” he added. “Weight loss should remain a primary target for health policies together with promoting active lifestyles … Fighting obesity and inactivity is equally important; it should be a joint battle.”