How to lose weight and keep it off, from your own numbers
The evidence on losing weight and keeping it off, a worked plan from one set of numbers, and where researchers still disagree.
Health, explained simply.
Plain answers about your body’s numbers, from calories to heart rate, with a source behind every claim.
Weight management
Calorie targets, a pace you can keep, and the numbers that show whether it is working.
10 guides
How many calories should I eat to lose weight?
There is no single number. Here is how to estimate a starting target, why it is only a starting guess, and who should not set one alone.
What is a calorie deficit?
What a calorie deficit is, how big one to aim for, how to work one out, and the limits guidelines set.
BMI explained: what it measures and who it gets wrong
Body mass index in plain terms: the formula, the ranges, a worked example and the people it misjudges.
Waist size and waist-to-height ratio
One tape measure and one division. Here is how to get the number right, what the bands mean, and what the ratio cannot tell you.
Body fat percentage: scans, scales, calipers and the Navy method
Every method is an estimate. Here is how far off each one tends to be, and how to get a number you can follow over time.
Losing weight without losing muscle
Some of the weight you lose is not fat. Here is what the research says keeps more of it, and by how much.
Why is the scale stuck? Plateaus, water and the 3,500-calorie myth
What a stall usually is, why the same plan stops working, and what the evidence says about a slowed metabolism.
How fast can you safely lose weight?
The pace health agencies recommend, what it looks like for one person, and where the evidence is still argued.
Daily weigh-ins and trend weight: how to read the scale
What moves the number from one morning to the next, what the evidence says about weighing daily, and how to find the trend.
Work out your own numbers
Nutrition
Calories, protein, fiber and macros in grams, and the apps that count them.
10 guides
Calories and macros, explained: how to set targets you can keep
The four steps from a daily burn estimate to calorie and macro targets, with the official ranges, a worked example in grams, and what the trials say about which split to pick.
The best calorie tracking apps, compared on six criteria
Cronometer, MacroFactor, MyFitnessPal, Lose It!, Cal AI and Noom, scored on criteria you can check. Dalia Health publishes this guide and makes Dalia, which is listed separately and not ranked.
What is TDEE, and how is it calculated?
Total daily energy expenditure, in plain terms: what goes into it, how calculators estimate it, and where the estimate goes wrong.
How to count macros, step by step
How macro targets are set, how calories turn into grams, and how a starting split compares with the national ranges.
How accurate are photo calorie estimates?
What studies of AI photo estimates actually found, why big plates and hidden food trip them up, and why the error that matters most is the one that always points the same way.
BMR vs TDEE vs RMR: what each number means
Three numbers for how many calories you burn, what separates them, how a lab measures each one, and which one a calorie target should start from.
How much protein do you need?
The official minimum, the higher goal in the newest Dietary Guidelines, the ranges for training and for older adults, and a worked example in grams.
High-protein foods, ranked by protein per 100 calories
Grams per serving tell half the story. Here is how 31 common foods rank when you divide protein by calories, using USDA values you can check.
Fiber: how much you need and where to get it
The daily fiber targets, why they differ between sources, and the foods that close the gap, with every food value traced to its USDA entry.
Eating for a recomp: building muscle while losing fat
Who a recomp is likely to work for, what the studies say about protein, lifting and calories, and where the researchers still disagree.
Work out your own numbers
Heart health
Resting heart rate, what moves it, and when a reading is worth a call to a clinician.
2 guides
What is a good resting heart rate?
The normal range is wide, and each person has their own usual number. Here is how to read both.
Why is my heart rate high?
Many things raise your heart rate, from exercise to fever. Here are the common causes, the medical ones, and the signs that need care now.
Sleep
How sleep cycles work and how much sleep adults need.
1 guide
Sleep cycles explained: how long they last and how to time bed
What a sleep cycle is, how many you get a night, and how a sleep calculator uses them to suggest a bedtime.
Work out your own numbers
Recovery and HRV
What heart rate variability measures, and why your own baseline matters more than a chart.
1 guide
What is HRV, and what is a good number?
Heart rate variability is the small change in timing from one heartbeat to the next. Here is what it tells you, and what it does not.
Strength training
Estimating your strength from a set you have already done, and picking loads from it.
1 guide
How to estimate your one-rep max without testing it
How a set you have already lifted turns into an estimated max, how far to trust it, and how to use it to pick loads.
Work out your own numbers
Wearables explained
What the scores on your ring, watch or app are built from, and how far to trust them.
1 guide
How apps calculate your biological age
Each app means something different by "biological age". Here is what each one measures, what research uses instead, and how far to trust the number.
Calculators that show their work
Each one shows the formula with your numbers in it, and says who the estimate is wrong for.
- BMI CalculatorBody mass index from your height and weight, with what it can and can't tell you.
- TDEE and BMR CalculatorYour daily calorie burn, at rest and with activity, from the Mifflin-St Jeor equation.
- Calorie Deficit CalculatorA daily calorie target and a goal date for the weight you're aiming for.
- One-Rep Max CalculatorYour estimated max from a set you've done, plus loads for every rep range.
- Macro CalculatorDaily protein, carbs and fat in grams, from your calorie target.
- Sleep CalculatorBedtimes or wake times that fit whole sleep cycles.