How much protein should I eat per day?

Healthy sedentary adults need at least 0.8 g per kg of body weight to avoid deficiency. For active people aiming to preserve muscle while losing fat or build muscle, 1.6 to 2.2 g per kg is well-supported by the literature. Older adults benefit from the higher end to counter age-related muscle loss.

Are carbs really bad for you?

No. Carbohydrates are the body's preferred fuel for high-intensity activity and the brain's primary fuel under normal conditions. Refined carbs (white bread, sugar-sweetened drinks) are linked to worse health outcomes, but whole-food carbs (vegetables, legumes, whole grains, fruit) are not. Low-carb diets work for some people because they reduce calorie intake — not because carbs are inherently harmful.

What is a keto macro split?

Ketogenic eating restricts carbs to roughly 5% of calories (typically under 50 g per day) so the body switches to producing ketones from fat for fuel. We model keto as 70% fat, 25% protein, 5% carbs. Keto is well-studied for refractory epilepsy and shows mixed evidence for weight loss; it is not appropriate for everyone, especially people with kidney issues or pancreatitis history.

How do I know if my macros are working?

Give a plan 4–6 weeks. Track weight weekly (averaged across days), strength performance (in the gym), and energy/hunger levels. If weight is moving in the wrong direction or energy crashes, adjust calories first by 100–200 kcal, then macro composition. Avoid changing variables every few days — the signal-to-noise ratio is too low.

Should I weigh my food?

Most people benefit from 4–8 weeks of careful weighing to learn portion sizes accurately, then transition to estimates and only weigh occasionally for calibration. If weighing food triggers anxiety or rigid thinking, stop and work with a dietitian.

Can I just eat the percentages without tracking grams?

Yes. Start with the gram targets and use them to plan a few standard meals — say, breakfast, lunch, two snacks, and dinner. Once you know what hits the targets, you don't need to track every meal. Tracking is a learning tool, not a permanent practice.

Macro Calculator — Protein, carbs, fat

Macro Calculator

Daily protein, carbs, and fat targets · pick a split that fits your goal

Implements a published clinical formula — see citation

Maintained by TheHealthTools team. Not medical advice.

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Macro split

Picking the right macro split

Macronutrient ratios matter less than total calories for weight change and total protein for body composition. Within those two constraints, the right split is the one you can stick to. We offer four presets:

Balanced (30/40/30): default for most adults. Plenty of protein, room for whole-food carbs, sustainable fat.
High protein (40/35/25): best for fat loss and active individuals trying to preserve muscle.
Low carb (35/20/45): works for people who prefer fewer carbs but don't want to be in ketosis.
Keto (25/5/70): very low carb, ketosis-targeting. Effective for some — not recommended for endurance athletes, pregnancy, or kidney disease.

Protein per kg of body weight is the lever most worth thinking about. Sedentary people need at least 0.8 g/kg. Active people and those losing fat benefit from 1.6–2.2 g/kg. Older adults benefit from staying at the higher end to counter sarcopenia.

Frequently asked questions

For weight loss, the most important macro is protein — it preserves muscle mass during a calorie deficit and is the most filling per calorie. A high-protein split (40% protein, 35% carbs, 25% fat) at a 500 kcal deficit is a defensible default for most adults. Carbs and fats can be tuned to preference.