Its Body-Composition That Matters:
The original weight-table standards were designed for insurance purposes -- not as guides for nutrition and fitness. These tables never considered body-composition. Most world-class body-builders (usually less than 8% body-fat) would be categorized "obese" by the original weight-tables.
The way to measure and determine one's fat to lean muscle proportion is to determine body-fat percentage. The body-fat percentage is the percentage of an individual’s weight that is fat.