Keto, low carb, balanced: macro ratios compared

What is a macro ratio?

Macronutrients are protein, carbohydrate and fat. A macro ratio tells you what percentage of your daily calories comes from each. Protein and carbohydrate give 4 kcal per gram, fat gives 9 kcal.

First set your total calorie target (see how to calculate your daily calorie needs for how), then split those calories into macros with a ratio.

Does the ratio change weight loss?

The short answer: total calories are what mainly decide. In a two-year randomized trial comparing diets with different proportions of fat, protein and carbohydrate, weight loss was similar regardless of the ratio when calories were equal. Reviews of controlled feeding studies point the same way.

So when choosing a ratio, look at these questions: How full does it keep you? What does your training look like? Most importantly, which one can you keep up for months?

Four common ratios

Swipe sideways to see the table →

General (50 : 30 : 20)

Balanced and flexible. It doesn't restrict any food group and is the easiest starting point for most people. For those with an active lifestyle, carbohydrate supplying energy is an advantage.

Fitness (40 : 40 : 20)

High protein and moderate carbohydrate. It suits people who do resistance training and want to keep or build muscle mass. Check the gram equivalent of your protein target; on very high calorie days you don't need to go above 2.2 g/kg.

Low carb (20 : 40 : 40)

It clearly reduces carbohydrate but doesn't cut it entirely. It leaves room for vegetables, legumes and some whole grains. It suits people who don't like blood sugar swings or who prefer a high-protein pattern.

Keto (5 : 25 : 70)

Carbohydrate drops to about 20–50 g a day; the body uses ketones derived from fat for energy. In the first days you may notice fatigue, headaches and the "keto flu". In some people LDL cholesterol rises. It is hard to follow in social settings and when eating out.

Which one should you choose?

• If you're unsure, start with General. After two or three weeks, adjust based on fullness and energy level.
• If you train, Fitness makes the protein target easier.
• If you think carbs leave you hungry, you can try Low carb; it is far more flexible than keto.
• Choose keto only if you know why and you will really be able to follow it.
• Whichever ratio you choose, if your average weight doesn't match your goal for two or three weeks, review total calories first, not the ratio.

When should you see a professional?

If you are pregnant or breastfeeding, have diabetes, kidney, liver or cardiovascular disease, are under 18, or have had an eating disorder in the past, work with a doctor or dietitian instead of setting your macro ratio yourself.

Sources

1. Sacks FM et al. Comparison of weight-loss diets with different compositions of fat, protein, and carbohydrates. N Engl J Med. 2009;360(9):859–873.
2. Hall KD, Guo J. Obesity energetics: body weight regulation and the effects of diet composition. Gastroenterology. 2017;152(7):1718–1727.
3. Jäger R et al. International Society of Sports Nutrition position stand: protein and exercise. J Int Soc Sports Nutr. 2017;14:20.
4. World Health Organization. Healthy diet fact sheet, 2020.

This content is for information only and is not medical advice. Last updated: October 15, 2026.