Clinically Reviewed

Health Guides

Evidence-based articles written and reviewed by Rex, RN — registered nurse with 8+ years of clinical experience.

Calories & Weight Loss

What Is TDEE? How It's Calculated

The four components of daily energy expenditure and why a single calorie number is never the full picture.

TDEE for Women: Why the Numbers Are Always Different

How the menstrual cycle shifts calorie needs by up to 300 kcal/day — and what calculators miss.

Which BMR Formula Is Most Accurate?

Mifflin-St Jeor vs Harris-Benedict vs Katch-McArdle — when each applies and by how much they differ.

How Many Calories Should I Eat to Lose Weight?

Step-by-step: finding your TDEE, choosing a safe deficit, and why the math always overestimates progress.

Why Your Calorie Deficit Isn't Working

Five evidence-based reasons weight loss stalls — TDEE error, logging mistakes, metabolic adaptation, and more.

How Long Will It Take to Lose Weight?

Why real timelines are 20–40% longer than simple math predicts — and how to set realistic expectations.

Body Composition

What Is a Healthy BMI?

WHO ranges, healthy weight by height, Asian-adjusted thresholds, and key limitations of BMI.

BMI vs Body Fat Percentage: Which Is More Accurate?

Four cases where BMI gets it wrong — and when body fat % gives a more meaningful picture.

How to Calculate Body Fat Percentage

Navy method, calipers, BIA, and DEXA — accuracy comparison and how to measure at home.

What Is My Ideal Weight?

Four clinical formulas for ideal weight — and why none of them should be treated as a fixed target.

Nutrition & Fitness

What Are Macros?

Protein, carbohydrates, and fat — what each does, how to calculate your targets, and five diet approaches compared.

How to Build Muscle: Calorie Surplus Guide

How much surplus you actually need, realistic muscle gain rates, and the muscle-to-fat ratio by bulk strategy.

How Much Water Should I Drink?

Evidence-based daily intake targets by body weight, activity level, and climate — beyond the "8 glasses" rule.