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Body Composition

10 articles in this pillar.

Body Composition

BMI vs. Body Fat Percentage: Which Actually Matters?

BMI is everywhere, but it can't tell muscle from fat. Here's what each measure captures, where each one misleads, and how to read them together.

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Body Composition

What Is a Healthy BMI? Understanding the WHO Categories

Where the 18.5–24.9 range came from, what the categories above and below it actually mean, and how much weight to put on the number.

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Body Composition

How to Measure Body Fat at Home (Without Calipers)

A practical guide to the U.S. Navy tape method — where to place the tape, how to avoid the common errors, and how it compares to scales and scans.

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Body Composition

Waist-to-Hip Ratio vs. BMI: Which Predicts Health Risk Better?

Where you store fat matters as much as how much you carry. What waist-to-hip ratio measures, what the WHO thresholds mean, and when it beats BMI.

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Body Composition

Why the Scale Isn't Telling You the Whole Story

Muscle and fat weigh the same but occupy different space. What that means for tracking progress, and why the scale can stall while your body changes.

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Body Composition

Ideal Weight Formulas Compared: Devine, Robinson, Miller and Hamwi

Four formulas, four different answers, all from the same height. Where they came from, why they disagree, and what to use instead of any of them.

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Body Composition

BMI by Age and Sex: Why One Table Doesn't Fit Everyone

The same 18.5–25 range is applied to a 22-year-old man and a 78-year-old woman. Where that breaks down, what the alternatives are, and why the AMA changed its position in 2023.

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Body Composition

Ideal Weight vs. Healthy Weight: Which Target Should You Use?

One is a number invented for drug dosing. The other is a range derived from mortality data. They are not the same thing, and only one of them is a sensible goal.

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Body Composition

Reading a Body Fat Percentage: What's Athletic, What's Risky

The categories, why men's and women's differ by ten points, why essential fat is a floor rather than a target, and how much to trust the number your method gave you.

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Body Composition

What Is My Body Shape? How to Measure, and What It Does Not Mean

Hourglass, pear, apple, rectangle, inverted triangle — where the categories come from, how to take the three measurements properly, and which of your numbers actually predicts anything.

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