By Mili Jayadeep | Science Editor
Heart disease is a huge contributor to death in the UK and across the world. It can develop over time due to a number of risk factors such as leading an unhealthy lifestyle, having diabetes and can also be associated with obesity. A new study by researchers at the University of California, Los Angeles Health Sciences report data showing lower heart disease risk in women with higher levels of body fat. It is well known that high levels of fitness, which includes men and women with higher muscle mass have superior cardiovascular health. However, it was shown according to the data collected from this study that a sex difference in better cardiovascular fitness was seen when comparing women and men with higher body fat percentage.
National health survey data was analysed and evaluated by the researchers over 15 years, which showed that in deaths related to heart disease was 42% lower in women with high muscle and fat percentage compared to those with low muscle and body fat content. This advantage was not seen in women with high muscle mass and low body fat content. This difference in risk was not as significant in males as it was in females. Also, males with a higher muscle mass and lower body fat was favoured in terms of risk reduction.
These findings presented by these researchers can be surprising to many, which may seem paradoxical to the obesity problem. It is well known that obesity is becoming an increasing problem in the western world. According to the NHS, 1 in 4 adults in the UK are considered obese. It is a problem that is also known to be associated with the prevalence of many chronic conditions such as diabetes, heart disease, stroke and certain cancers. Yet this study shows that women with higher body fat may have a lowered risk of heart disease. This could be owing to a number of factors, For instance, the fat distribution differences between men and women could affect cardiovascular disease risk. Women tend to carry fat in the leg and gluteal region whereas men carrying a high fat percentage tend to carry the fat in the abdominal region. Research shows that fat in the gluteofemoral region, more common in women may have a protective effect against cardiovascular disease. Also, the fat cell biological activity is shown to be different in men and women due to hormonal differences, which may account for the difference in protection. A hormone known as leptin responsible for appetite control may also play a role in the sex differences seen.
The findings from this study can be important in approaching cardiovascular disease treatment. The previous ongoing guidance for reducing disease risk is focused on promoting weight loss. Yet, this study highlights the importance of other existing factors and the complex interactions of different cell types, hormones and metabolic factors that can contribute to disease risk. Perhaps the best strategy for reducing disease risk would be to increase muscle mass and account for sex differences in both men and women. Further research is necessary to determine how this can be implemented for patients as a practical treatment strategy.