Calculating Macronutrient Ratio MIfflin-St Jeor formula, which look like this; Men: 10 x weight (kg) + 6.25 x height (cm) – 5 x age(y) + 5 Women: 10 x weight (kg) + 6.25 height (cm) – 5 x age (y) – 161 For instance, the men weight is 80kg, height is 168cm and 38 years old Men: 10 x 80 (kg) + 6.25 x 168 (cm) – 5 x 38(y) + 5 = 800 + 1050 – 190 + 5 = 1665 You can see that he should be eating 1,665 calories per day.