Which of the following statements is true?

• A. Fats contain more energy per gram than carbohydrates.
• B. Fats can act as the building blocks for new muscle tissue when the body lacks protein.
• C. Especially when at rest, fats provide less than 25% of the total energy we use.
• D. All of the above are true.

Answer: (A)

Verified step by step guidance

1. Understand the energy content of macronutrients: Fats provide approximately 9 kcal per gram, while carbohydrates and proteins provide about 4 kcal per gram. This makes fats more energy-dense than carbohydrates or proteins.
2. Analyze the role of fats in muscle tissue synthesis: Fats are not used as building blocks for muscle tissue. Proteins are the primary macronutrient responsible for muscle repair and growth, as they provide amino acids necessary for this process.
3. Evaluate the energy contribution of fats at rest: At rest, fats typically provide a significant portion of the body's energy needs, often exceeding 25% of total energy expenditure. This is because the body relies on fat stores for energy during low-intensity activities.
4. Review the statement 'All of the above are true': Since the second and third statements are incorrect based on the analysis above, the option 'All of the above are true' cannot be correct.
5. Conclude which statement is true: Based on the analysis, the first statement, 'Fats contain more energy per gram than carbohydrates,' is the correct answer.