How does the basal metabolic rate (BMR) in children compare between boys and girls?

How does the basal metabolic rate (BMR) in children compare between boys and girls?

• A. It is slightly higher in boys than in girls at all ages
• B. It is slightly higher in girls than in boys at all ages
• C. It is about the same in boys and girls at all ages
• D. It is higher in girls during adolescence only

Answer: (A)

BMR in children tracks closely with body size and lean mass. Boys generally have more lean body mass and, especially after puberty, greater muscle mass than girls. Muscle tissue uses more energy at rest than fat tissue, so the resting energy expenditure is a bit higher. This leads to a modest but consistent difference: boys tend to have a higher BMR than girls at all ages. The idea that girls would have higher BMR, that it’s the same, or that the difference only appears during adolescence doesn’t match the typical pattern observed, where the advantage in boys persists across childhood and adolescence due to body composition and growth factors.

BMR in children tracks closely with body size and lean mass. Boys generally have more lean body mass and, especially after puberty, greater muscle mass than girls. Muscle tissue uses more energy at rest than fat tissue, so the resting energy expenditure is a bit higher. This leads to a modest but consistent difference: boys tend to have a higher BMR than girls at all ages. The idea that girls would have higher BMR, that it’s the same, or that the difference only appears during adolescence doesn’t match the typical pattern observed, where the advantage in boys persists across childhood and adolescence due to body composition and growth factors.