In the context of energy balance, approximately how much body fat mass could be gained if a person consumes a surplus of 400 kcal, assuming $3500\mathrm{kcal}$ is equivalent to about 1 lb of body fat?

• A. About 1 lb (≈ 454 g)
• B. About 2 lb (≈ 907 g)
• C. About 0.5 lb (≈ 227 g)
• D. About $\frac{400}{3500}$ lb (≈ 0.11 lb, about 50 g)

Answer: (D)

Verified step by step guidance

1. Understand the relationship between energy surplus and body fat gain: 3500 kcal is approximately equivalent to 1 pound of body fat.
2. Identify the given energy surplus: 400 kcal.
3. Set up the proportion to find the amount of body fat gained from the surplus: body fat gain (in pounds) = \frac{energy surplus (kcal)}{3500 \text{ kcal/lb}}.
4. Substitute the given values into the formula: body fat gain = \frac{400}{3500} \text{ lb}.
5. Interpret the result to understand that a 400 kcal surplus corresponds to about 0.11 lb (approximately 50 g) of body fat gained.