Doctor Le Ba Ngoc, Head of General Internal Medicine at Tam Anh General Hospital Hanoi, states that the core objective in treating obesity today extends beyond simple weight loss to include reducing fat and preserving muscle mass.
The body mass index (BMI) is a measure of overweight and obesity based on the correlation between weight and height. While it is the most convenient and common tool for classifying body status, BMI does not reflect the body's internal composition. This means the index does not differentiate between fat mass and lean mass, or skeletal muscle mass.
"In reality, two individuals with the same BMI can have entirely different disease risks depending on their visceral fat percentage", Doctor Ngoc explains. Excessive visceral fat accumulation in the abdominal area causes metabolic disorders and leads to many dangerous health conditions. Some people with a normal BMI (18.5 - 22.9) but a waist circumference exceeding recommended limits (over 80 for women and over 90 for men) still face a high or moderate risk of disease.
According to Doctor Ngoc, individuals undergoing weight loss should ensure that muscle loss remains below 25% of their total body weight. Losing skeletal muscle mass decreases the metabolic rate, making it easy for the body to regain weight even with reduced food intake. Muscle deficiency diminishes physical strength, increases the risk of illness, and restricts mobility, especially in older adults. Low skeletal muscle mass can impair strength, is linked to insulin resistance, increases the risk of sarcopenic obesity, and raises obesity-related mortality.
To preserve muscle mass during weight loss, patients must closely coordinate nutrition and exercise. A focus on increasing protein intake in the diet is crucial for maintaining lean muscle mass. Concurrently, resistance training is necessary at least two to three times per week to stimulate muscle development. During exercise, skeletal muscles release hormones that can counteract the harmful effects of fat tissue, supporting cardiovascular protection and enhancing metabolism.
Doctor Ngoc advises those aiming for weight loss not to solely focus on the number on the scale. Instead, they should monitor fat percentage, changes in waist circumference, and body firmness to assess the effectiveness of their weight loss scientifically.
Thuy Hanh
