Chronic disease risk factors such as abdominal obesity and circulating fatty acids have a strong association with overweight and obesity. However, there is limited evidence around abdominal obesity and fatty acids after weight loss has occurred.
Background
A high amount of fat in the abdominal area is linked to many obesity-related health problems, including insulin resistance, type 2 diabetes and metabolic syndrome. Caloric restriction is more likely to reduce visceral fat compared to other weight loss options.
There have been links made between visceral fat and serum fatty acids in overweight individuals. However, there is limited data when it comes to the changes to these after weight loss has occurred.
Researchers set out to explore the impact on abdominal fat and circulating fatty acids in overweight individuals undergoing weight loss.
The study
80 participants with high visceral fat area (VFA) were recruited into the 12 week study. They were randomized into either a mild caloric restriction (300kcal/day) group or control group. The research study took place in Seoul, Korea.
Inclusion criteria included a BMI of 25 or more and aged 20-60 years old. Exclusion criteria included pregnancy, hypertension, CVD, thyroid disease, type 2 diabetes or any medication that could affect body weight or blood sugar levels.
Participants were also excluded if they consumed more than the recommended limit of alcohol per day or had recently lost weight.
The calorie restriction group received an individualised nutritionally balanced plan from a nutritionist. They received instructions including food choices, cooking methods, food substitutions and limits on simple sugars. The control group were instructed to maintain their usual diet and physical activity for the study period.
The findings
The calorie restricted group experienced significant weight loss and reduced their BMI, waist circumference and systolic BP. They also experienced a 17.7cm² reduction in VFA. When compared to control, the group showed greater reductions in serum triglycerides, insulin and HOMA-IR.
Furthermore, after adjusting for baseline values, the calorie restricted group experienced reductions in total saturated fatty acids.
The calorie restricted group experienced a significant decrease in fat percentage and fat mass. However, there was also a significant decrease in lean body mass.
Conclusions
The researchers concluded that mild weight loss can help to reduce abdominal obesity and fatty acid profiles. The further implications include the reduction of disease risk factors, particularly VFA.
Additionally, mild caloric restriction can be sufficient to offer health benefits to overweight individuals with high VFA. The researchers suggested that eating behaviour modification of mild calorie restriction could be an effective therapy for chronic diseases such as CVD and type 2 diabetes.
However, the loss of lean body mass suggests that this intervention would be best combined with a physical activity program to maintain optimal muscle mass levels.
References
Lee, Y.J., Lee, A., Yoo, H.J., Kim, M., Kim, M., Jee, S.H., Shin, D.Y. and Lee, J.H., 2018. Effect of weight loss on circulating fatty acid profiles in overweight subjects with high visceral fat area: a 12-week randomized controlled trial. Nutrition Journal, 17(1), p.28.