IndexBody Journal

Evidence-based articles on fat loss, body composition, nutrition, and fitness. All written and reviewed by IndexBody Editorial with citations to peer-reviewed research.

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Most Read · Body Composition
What Is BMI? Complete Guide
WHO classifications, limitations, and better alternatives explained.
Most Read · Nutrition
How Many Calories Should I Eat?
Mifflin-St Jeor equation explained with real examples.
Essential · Fat Loss
How to Calculate a Calorie Deficit
Step-by-step with real numbers. Safe vs aggressive deficit explained.
How Our Health Content Is Researched

Every article on IndexBody is written using primary sources — peer-reviewed research, clinical guidelines, and data from established public health authorities. We do not publish health claims without a corresponding citation. Our primary reference sources include:

WHO
World Health Organization — BMI classifications, physical activity guidelines, nutritional standards
NIH / PubMed
National Institutes of Health and peer-reviewed journals via PubMed
CDC
Centers for Disease Control and Prevention — healthy weight, chronic disease data
USDA / DGA
Dietary Guidelines for Americans and USDA FoodData Central

All content is educational and informational only. It is not a substitute for professional medical advice, diagnosis, or treatment. Our calculators provide estimates based on population-level formulas — individual needs vary.

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Body Composition
Body Composition
What Is BMI? Complete Guide
WHO classifications, limitations, and better alternatives.
Body Composition
BMI vs Body Fat: Which Is Better?
Why body fat % outperforms BMI for most people.
Body Composition
Body Fat % Explained
Healthy ranges by age and sex, how to measure accurately.
Body Composition
BMI for Men: Complete Guide
How BMI applies to males — visceral fat, athletes, and more.
Body Composition
BMI for Women: Complete Guide
Hormonal differences, menopause, and pregnancy considerations.
Body Composition
Healthy Body Fat by Age
ACE reference ranges for every age group and goal.
Body Composition
Waist-to-Height Ratio Guide
The single measurement that predicts disease better than BMI.