English-Chinese/Proteins provide as much energy density as carbohydrates

As a fuel, proteins provide as much energy density as carbohydrates: 4 kcal (17 kJ) per gram; in contrast, lipids provide 9 kcal (37 kJ) per gram.

作为燃料，蛋白质提供与碳水化合物一样多的能量密度：每克4千卡（17千焦）; 而脂质每克提供9千卡（37千焦）.