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Plain-English guides on GLP-1 medications, body composition, and keeping your muscle while you lose weight.
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AI nutritionist: what ChatGPT gets right and wrong about your diet
AI nutritionist tools and ChatGPT promise personal diet advice. What they are genuinely good at, where they fall short, and how to get more out of them.
Read guideCan ChatGPT calculate your BMI and body fat?
ChatGPT can usually work out BMI, but body fat is where it guesses. Here is what it gets right, where it goes wrong, and how to get numbers you can trust.
Read guideChatGPT for health: what it is good at, and where it is risky
Hundreds of millions of people ask ChatGPT health questions every week. A clear-eyed guide to where it genuinely helps, where it is risky, and how to use it safely.
Read guideHow to use ChatGPT for weight loss: prompts that work
ChatGPT is a strong weight loss thinking partner once you feed it real numbers. The prompts that actually work, and how to make it track your progress.
Read guideThe best ChatGPT meal plan prompts (with a free template)
ChatGPT can build a meal plan in seconds, but a generic one ignores your calories and protein. The prompts and a reusable template that produce a plan you will actually follow.
Read guideWill you lose muscle on Ozempic or Mounjaro?
GLP-1 medications cause real weight loss, but a large share can be muscle. Here is why it happens and how to protect your lean mass.
Read guideWeight vs body composition: look beyond the scale
The scale only tells you total weight. Body composition shows whether you are losing fat or muscle, which is what actually matters.
Read guideHow much protein on a GLP-1 medication?
Appetite drops on GLP-1 medications, which makes protein hard to hit. Here is a simple target and practical ways to reach it.
Read guideOzempic vs Mounjaro: what is the difference?
Both drive serious weight loss, but they are not the same drug. Here is how semaglutide and tirzepatide differ, and what it means for your body.
Read guideWhat happens to your weight when you stop a GLP-1?
Many people regain weight after stopping a GLP-1 medication. The muscle you kept on the way down is a big part of whether it stays off.
Read guideWhat is FFMI, and why it beats BMI for muscle
FFMI scales your lean mass to your height, so unlike BMI it does not penalise muscle. Here is what it means and how to read it.
Read guideBody fat percentage explained
What body fat percentage means, what counts as healthy for women and men, and how the common methods of measuring it compare.
Read guideWhy BMI is flawed (and still useful)
BMI cannot tell muscle from fat and ignores age, sex and fat distribution. Here is what it gets wrong, and how to use it well anyway.
Read guideWaist-to-height ratio: the simplest health check
One measurement and one rule of thumb. Why waist-to-height ratio is a better quick health screen than BMI for many people.
Read guideBMI for women and men: what is different
The BMI formula and categories are the same for everyone, but body composition is not. Here is what that means for reading your number.
Read guideBMI categories explained
Underweight, normal, overweight, obese: what each BMI category means, where the cut-offs come from, and how to read them sensibly.
Read guideBMI vs body fat percentage: which should you trust?
BMI and body fat percentage measure different things. Here is when each is useful and why body fat usually wins for understanding your health.
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