Build muscle on what actually works
The supplements that move the needle for size and strength, ranked honestly. Research-checked, no bro-science, no invented studies.
3D Body Lab
See what a BMI looks like on a 3D body. Resize muscle groups in inches or centimeters, put a 12 oz soda can next to the model for scale, and explore every muscle with exercise videos from US trainers. Free, no sign-up.
Shop by goal
Curated picks per category. Every “Check price” is an affiliate link to iHerb.
Shop every pick
Real products, one pick per category. Every “Check price” opens iHerb in your own country and currency. AINutry may earn a commission from qualifying purchases, at no extra cost to you.
Nine free tools, no sign-up
Calculators, quizzes and planners you can use right now.
New 3D Body Lab
See what a BMI looks like on a 3D body, resize muscle groups in inches or centimeters, and explore every muscle with exercise videos.
Open the 3D Body LabMacro Calculator
Your exact calories and macros to bulk, cut, or recomp, from the Mifflin-St Jeor equation.
Calculate my macrosSupplement Stack Builder
Answer 5 quick questions and get a personalized supplement stack built around your goals, diet, and budget.
Build my stackIdeal Diet Quiz
Answer 7 questions about your lifestyle and goals to find the diet approach that fits you.
Take the quizMetabolic Age Calculator
Answer 8 questions about your daily habits and get an estimate of your metabolic age.
Estimate my ageGut Health Score Quiz
Fifteen questions, about three minutes, and a free score for your gut health.
Take the gut quizGLP-1 Diet Checker
Answer 10 quick questions to see how GLP-1 friendly your diet is.
Check my dietIntermittent Fasting Schedule Generator
Pick your protocol, set your wake-up time, and get a daily fasting timeline.
Build my scheduleCircadian Nutrition Clock
Enter your schedule to see your optimal eating window.
Open the clockLatest guides
Build your stack in 60 seconds
Tell us your goal and we’ll email you a research-backed stack: the exact doses and where to buy each. Want the full 5-step version with budget and training age? Use the Supplement Stack Builder instead.
Practical nutrition guides
Start with a food log you can check, realistic uses for AI, and questions to bring to a healthcare professional.
Honest by design
What makes this different from every other supplement affiliate site.
Named studies, or we say so
Where we cite a study, it’s a real, named, peer-reviewed paper you can open. Where we haven’t added one yet, we say so instead of guessing.
Affiliate links, disclosed
A pick only makes the list if it hits an effective, studied dose. We disclose every affiliate link.
Doses that match the research
A product only makes a list if it hits the dose the studies actually used. Underdosed “clinically inspired” blends don’t count.