BMI Calculator

Reaching and Keeping a Healthy Weight

If your BMI sits outside the healthy range, the first useful step is to remember what that number is and is not — a screening signal, not a diagnosis, and blind to muscle, fat distribution and everything else that matters. Read understanding BMI before drawing conclusions from it.

If a conversation with your provider confirms that losing weight would genuinely benefit your health, what follows is the part most weight-loss content gets wrong: the difficulty is not knowing what to do, it is doing it for long enough that it stops being a project.

A realistic rate of change

Guidance consistently converges on 1–2 lbs (roughly 0.5–1 kg) per week, achieved through a moderate daily deficit of about 500–750 calories. That is deliberately unexciting, and it is the rate with the best evidence for being sustained.

Faster loss is achievable and mostly counterproductive: more of the loss comes from muscle, adherence collapses sooner, and the regain is well documented. A 5–10% reduction in body weight is enough to produce meaningful improvements in blood pressure, blood glucose and lipids — which is a far more useful target than a number on a chart.

What has the best evidence

• A moderate, sustained calorie deficit — the mechanism behind every diet that works, whatever it is branded as.
• Adequate protein, which preserves muscle during weight loss and is the most satiating macronutrient.
• Resistance training two to three times a week. Protein gives your body the material to keep muscle; training gives it the reason. Together they change what you lose, not just how much.
• Aerobic activity, with about 150 minutes a week of moderate intensity as the usual guideline — as much for cardiovascular and mental health as for the calorie cost.
• Sleep. Short sleep reliably increases appetite and cravings, and it is the most commonly ignored lever.
• Self-monitoring. Logging food, even imperfectly and briefly, is one of the more consistent predictors of success — largely because it makes the invisible visible.
• Whole foods over ultra-processed ones, which tends to reduce intake without deliberate restriction.

Things worth ignoring

• "Fat-burning" supplements. Effects are small to nonexistent, the category is poorly regulated, and some products have been withdrawn for undeclared ingredients.
• Detoxes and cleanses. Your liver and kidneys do this already. What you lose is water and food volume.
• Spot reduction. You cannot choose where fat comes off. Targeted exercise builds muscle in that area; it does not preferentially burn the fat over it.
• Eliminating a whole food group without a medical reason. It usually works by accidentally cutting calories, and it rarely lasts.

Measuring progress without a scale

Weight fluctuates by several pounds a day on fluid alone, so a single reading tells you very little. More informative signals:

• Waist circumference, which often changes while weight stalls
• How clothes fit
• Strength and stamina in training
• Energy, sleep quality and mood
• Blood pressure and lab results at your next check-up
• The trend across several weeks rather than any single day

When to involve a professional

Speak to a healthcare provider or a registered dietitian if you have diabetes, heart disease, kidney or liver disease, thyroid problems or are pregnant; if you take medication that affects weight or appetite; if you have a history of disordered eating; if weight has changed substantially without you trying; or if repeated genuine efforts have not worked. That last one is a clinical signal, not a character flaw — and it is often where an underlying cause is found.