What is the 4 4 9 rule?

What is the 4 4 9 rule? This simple guideline is commonly used in nutrition to estimate how many calories come from carbohydrates, protein, and fat.

The 4-4-9 rule is a quick way to estimate calories from macronutrients: each gram of carbohydrate provides about 4 calories, each gram of protein about 4 calories, and each gram of fat about 9 calories. To estimate a food’s calories, multiply grams of carbs by 4, protein grams by 4, fat grams by 9, then add the totals. For example, a meal with 50 g carbs, 30 g protein, and 15 g fat has roughly 455 calories using this approach. The rule is an approximation, because fiber, sugar alcohols, and processing can slightly change actual usable energy. Nutrition labels may not match this formula perfectly, but the rule is accurate enough for planning and tracking.

To apply this rule to your own meals and daily target, use our calorie calculation tool to estimate how many calories you need based on your personal details.

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