Last Updated: November 3, 2021

Your weight is the result of your body’s fight against gravity. The ideal weight-loss diet will maximize fat loss and minimize fat-free mass loss.


Mass is a measure of how much matter is in an object. Unlike its weight, the mass of an object is constant. If an object’s mass is 1 gram on Earth, its mass is 1 gram on the Moon.

An object’s weight is its relative mass. Unlike mass proper, weight is affected by gravity: it will be different on Earth and on the Moon; it can even vary on Earth (a given object is slightly heavier at sea level than at the top of a mountain, and at the equator than at the poles).

For our purpose, however, mass and weight and pretty much interchangeable. The “weight” in “water weight” and the “mass” in “fat mass” are matters of convention. When “weight” is used alone, it refers to body weight.

Examine Database: Weight
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