Understanding Ideal Weight Formulas
Calculating "ideal" weight is not about trying to achieve a specific number for aesthetics, but rather finding a range that is statistically associated with good health and longevity. Different formulas have been developed over the years for different purposes.
The 4 Major Formulas
- Robinson (1983): Originally developed for the layout of recommended weights in the Metropolitan Life Insurance Company tables. It is often used as a general standard.
- Miller (1983): Derived from the Robinson formula but adjusts for body frame size assumptions, often resulting in slightly higher estimates.
- Devine (1974): The most widely used formula in medical settings, particularly for calculating drug dosages (like antibiotics) that are distributed in lean tissue.
- Hamwi (1964): A simple "rule of thumb" formula used for decades in nutrition counseling: 106 lbs for 5ft + 6 lbs per inch for men, and 100 lbs for 5ft + 5 lbs per inch for women.
Limitations
None of these formulas account for body composition (muscle vs. fat) or bone density. An athlete with high muscle mass may be classified as "overweight" by these formulas despite having low body fat. Conversely, someone with low muscle mass and high body fat might be considered "ideal". Always use these numbers as a guideline in conjunction with other metrics like Body Fat Percentage and Waist-to-Hip Ratio.