How this works
We start from your calorie target (see the calorie calculator for how that’s set).
Protein is set at 1.2 g per kg when maintaining and 1.6 g per kg when losing or gaining, capped at 35% of energy.
Fat is set at around 30% of energy — within the UK guideline of no more than 35% — and never below 0.6 g per kg.
Carbohydrate makes up the rest, which usually lands close to the UK recommendation of about half your energy from carbohydrate. Fibre is set at 30 g, the UK recommendation for adults.
Energy from each gram: protein 4 kcal, carbohydrate 4 kcal, fat 9 kcal (UK labelling conversion factors).
This tool gives general information, not medical advice. If you have a health condition, are pregnant, or are worried about your eating or weight, please speak to your GP or a registered dietitian.
Questions people ask
Do I need to hit my macros exactly?
No. Being roughly in range over the week matters far more than hitting exact grams each day.
Is low-carb better for weight loss?
Weight change depends mainly on overall energy balance. The best split is one you can keep up and that includes plenty of fibre, fruit and vegetables.
Why is fibre included?
UK guidance recommends 30 g of fibre a day for adults, and most people eat less than that. Fibre also helps meals feel more filling.
Sources
- SACN (2015). Carbohydrates and Health
- SACN (2019). Saturated fats and health
- Regulation (EU) No 1169/2011 as retained in UK law, Annex XIV: conversion factors for energy
- Mifflin MD, St Jeor ST et al. (1990). A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr 51(2):241–247