Protein is the nutrient your body uses to build and repair muscle, and to make enzymes, hormones and immune cells. You need some every day, because your body does not store protein the way it stores fat or carbohydrate.
The question is how much. The answer depends mostly on three things: your body weight, how active you are, and whether you are trying to build muscle, lose fat or simply stay healthy.
Key points
- The official minimum is 0.8 g of protein per kg of body weight (0.36 g per lb).
- Active people usually do better with 1.2–1.6 g/kg.
- To build muscle, aim for 1.6–2.2 g/kg. When losing fat, 1.6–2.4 g/kg protects muscle.
- Adults over 65 need at least 1.0–1.2 g/kg.
- Spread your protein across three to five meals.
The short answer
| Situation | Grams per kg | Grams per lb | Example: 70 kg (154 lb) |
|---|---|---|---|
| Minimum for sedentary adults | 0.8 | 0.36 | 56 g |
| Regular exercise | 1.2–1.6 | 0.55–0.73 | 85–110 g |
| Building muscle | 1.6–2.2 | 0.73–1.0 | 110–155 g |
| Losing fat while training | 1.6–2.4 | 0.73–1.1 | 110–170 g |
| Adults over 65 | 1.0–1.2 or more | 0.45–0.55 | 70–85 g |
For your own numbers, including protein per meal, use the protein calculator.
Why the RDA is a minimum, not a target
The Recommended Dietary Allowance (RDA) of 0.8 g/kg is the amount that covers the basic needs of almost all healthy, mostly sedentary adults. It was set to prevent deficiency, not to support training, muscle growth or healthy aging.
For anyone who exercises, research consistently finds benefits at higher intakes. The International Society of Sports Nutrition recommends 1.4–2.0 g/kg a day for most exercising people.
How much protein to build muscle
A large 2018 meta-analysis of 49 studies found that protein intake boosted muscle gains from resistance training up to around 1.6 g/kg a day, with little extra benefit above that on average. Because people differ, the researchers suggested that going up to 2.2 g/kg covers nearly everyone.
So for muscle growth:
- 1.6 g/kg (0.7 g/lb) is a strong target for most people.
- 2.2 g/kg (1 g/lb) is a sensible upper end if you want to be sure.
Protein alone does not build muscle, though. It supplies the building blocks; resistance training provides the signal to grow. Read more in how much protein you need to build muscle.
How much protein when losing fat
In a calorie deficit, your body is more likely to break down muscle for energy. Eating more protein helps you keep it. It also keeps you fuller and burns slightly more energy during digestion than carbs or fat.
Most people losing fat do well with 1.6–2.4 g/kg a day. Very lean athletes in a hard diet may benefit from even more, measured against their lean mass.
Protein needs as you get older
From around age 65, muscles respond less strongly to each serving of protein, a process called anabolic resistance. Expert groups recommend at least 1.0–1.2 g/kg a day for healthy older adults, and 1.2–1.5 g/kg for those who are active or recovering from illness. Getting 25–30 g of protein at each main meal helps.
Body weight or lean mass?
Protein needs follow muscle, not fat. For most people, using total body weight works fine. If you carry a lot of body fat, total weight gives an inflated number. Two simple fixes:
- Use your goal weight instead of your current weight.
- Use an adjusted body weight, which is what our calculator does automatically when your BMI is 30 or higher.
How to spread protein across the day
Your daily total matters most, but distribution helps. Around 0.4 g/kg per meal, or roughly 25–40 g, across three to five meals is a practical pattern that keeps muscle building active throughout the day. See how much protein to eat per meal for details.
Can you eat too much protein?
In healthy adults, high-protein diets have not been found to harm kidney function. A 2018 meta-analysis found no difference in kidney function between people eating higher and lower amounts of protein. The practical limit is your plate: very high protein leaves less room for carbohydrates that fuel training and for fibre-rich plants.
If you have kidney disease, protein needs are different and should be set with your doctor.
Getting enough protein from food
Build each meal around a protein source: meat, fish, eggs, dairy, tofu, tempeh or legumes. Protein powder is a convenient top-up, not a requirement. The macro calculator shows how your protein fits with carbs and fat.