How Much Protein Do I Need? Complete Guide

Protein is the most talked-about nutrient in fitness and nutrition — and for good reason. It builds and maintains muscle, keeps you fuller than carbohydrates and fat, and plays a vital role in nearly every function in your body. With Kalori's photo-based calorie tracking, you can easily keep track of your protein intake.

But how much protein do you actually need? The answer depends on your weight, activity level, and goals. Calculate your personal macro targets with our macro calculator.

Short answer: 1.6–2.2 g per kg of body weight

For most physically active people, the research-based recommendation is:

Example: A 75 kg person who exercises and wants to build muscle should eat 120–165 g of protein per day (75 x 1.6 to 75 x 2.2).

The Norwegian Directorate of Health recommends that 10–20% of energy intake comes from protein for adults (source).

Why is protein so important?

Muscle building and maintenance

Protein is the building block of your muscles. When you exercise, you break down muscle fibres that are then repaired and built back stronger — provided you get enough protein. Without sufficient protein, you can train as hard as you want without seeing results. The International Society of Sports Nutrition (ISSN) recommends 1.4–2.0 g of protein per kg of body weight for physically active individuals (source).

Satiety

Protein is the most satiating nutrient. Research shows that a higher protein intake can reduce total food intake by 10–25%, simply because you feel fuller.

This makes protein a powerful tool for weight loss — you eat less without having to "starve" yourself.

Thermic effect

Your body uses energy to digest food. Protein has the highest thermic effect — your body uses about 20–30% of protein calories just to digest it. By comparison, only 5–10% is used for carbohydrates and 0–3% for fat.

Muscle preservation during weight loss

When you are in a calorie deficit, your body will burn both fat and muscle. A high protein intake minimises muscle loss and ensures that most of the weight you lose comes from fat.

High-protein foods

Here are some of the best protein sources:

Animal sources

Vegetarian and vegan sources

How to get enough protein every day

1. Include protein in every meal

Spread your protein intake evenly throughout the day — 20–40 g per meal is optimal for muscle building. Three main meals plus one protein-rich snack covers the needs of most people.

Breakfast: Eggs + toast, or Skyr with nuts Lunch: Chicken or salmon salad Dinner: Fish or meat with vegetables and rice Snack: Cottage cheese, protein bar, or nuts

2. Use simple protein-packed foods

Short on time? These foods give you plenty of protein with minimal effort:

• Skyr or Greek yoghurt (buy 1 kg tubs)
• Boiled eggs (boil 6 on Sunday evening)
• Cottage cheese
• Protein bars (choose ones with at least 20 g protein)
• Shrimp (pre-cooked from the store)

3. Track your protein intake

Most people overestimate how much protein they eat. Use a calorie tracker like Kalori to log your food intake — then you can see exactly how much protein you are actually getting.

Track your protein intake automatically: Take a photo of your food with the Kalori app, and AI calculates protein, calories, and macros for you. Download for free.

Protein timing and distribution

How you distribute protein across the day matters almost as much as how much you eat. Research on muscle protein synthesis (MPS) suggests there is a per-meal ceiling — roughly 0.4 g per kg of body weight (about 25–40 g for most adults) — beyond which extra protein in a single sitting contributes less to muscle growth.

That makes the practical recommendation: 3–5 evenly spaced meals of 25–40 g protein each rather than two large servings. A 75 kg person hitting 150 g/day might split it as 35 g breakfast / 40 g lunch / 40 g dinner / 35 g snack.

Around training: the "anabolic window" is wider than the old 30-minute rule suggests. Studies show that consuming protein within roughly two hours of resistance training is sufficient — total daily intake matters far more than precise timing. Before sleep: 30–40 g of slow-digesting protein (such as casein from cottage cheese or Skyr) provides amino acids overnight and may improve recovery.

Protein quality: not all protein is equal

Two foods with the same gram of protein can deliver different building blocks. Protein quality is measured by how well a food's amino acid profile matches human needs and how digestible it is.

The current gold-standard score is DIAAS (Digestible Indispensable Amino Acid Score), which is gradually replacing the older PDCAAS scale. A score of 1.0 or higher means the protein supplies all essential amino acids in adequate proportions.

Complete vs. incomplete proteins

A complete protein contains all nine essential amino acids in adequate amounts. Most animal proteins are complete. Most plant proteins are not — but a few are: soy, quinoa, buckwheat, and hemp seeds all qualify as complete plant proteins.

For other plant sources, combining is the answer:

• Rice + beans (the classic) — rice is low in lysine, beans are low in methionine; together they form a complete profile
• Hummus + whole-grain pita — chickpeas + wheat
• Peanut butter + whole-grain bread — legume + grain
• Lentils + rice — same principle

You don't need to combine within a single meal — eating varied sources across the day is enough for most adults to hit the full essential amino acid profile.

Can you eat too much protein?

For healthy individuals, it is very difficult to eat "too much" protein from regular food. Research suggests the body can handle up to 3–4 g/kg without issues.

The myth that high protein intake damages your kidneys only applies to people who already have kidney disease. Healthy kidneys handle a high protein intake without problems.

Exception: If you have known kidney disease, you should consult your doctor about recommended protein intake.

Protein supplements — are they necessary?

No. You can meet your protein needs with regular food alone. But protein powder can be a practical supplement:

• After a workout when you do not have time for a full meal
• In smoothies to boost the protein content
• When you struggle to hit your protein target from food alone

Tip: Choose a protein powder with a short ingredient list and at least 80% protein.

Frequently asked questions

What happens if I don't eat enough protein?

Prolonged low protein intake can lead to muscle loss, weakened immune function, fatigue, and slower recovery after exercise. During weight loss, low protein leads to more muscle loss and less fat loss.

Do women need as much protein as men?

Yes, per kg of body weight the recommendations are the same. Since women generally weigh less, the absolute number is lower, but the ratio is the same.

How much protein after a workout?

20–40 g of protein within 2 hours after exercise is a good guideline. But total daily intake matters more than the exact timing.

Can I build muscle without protein supplements?

Absolutely. Protein powder is just a convenient supplement. Chicken, fish, eggs, dairy, and legumes provide all the protein you need.

Should I eat protein before or after a workout?

Timing matters less than your total daily protein intake. That said, research suggests it is beneficial to eat 20–40 g of protein within a couple of hours after exercise to support muscle building and recovery. Whether you eat it right before or right after your workout makes little difference — what matters most is hitting your daily protein target.

Sources

1. Norwegian Directorate of Health (Helsedirektoratet). Kostrådene og næringsstoffer (Dietary guidelines and nutrients). https://www.helsedirektoratet.no/faglige-rad/kostradene-og-naeringsstoffer
2. Jäger R, et al. International Society of Sports Nutrition Position Stand: Protein and exercise. JISSN (2017). https://jissn.biomedcentral.com/articles/10.1186/s12970-017-0177-8
3. Morton RW, et al. A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. British Journal of Sports Medicine (2018). https://pubmed.ncbi.nlm.nih.gov/28698222/
4. Leidy HJ, et al. The role of protein in weight loss and maintenance. American Journal of Clinical Nutrition (2015). https://pubmed.ncbi.nlm.nih.gov/25926512/
5. Helms ER, et al. A systematic review of dietary protein during caloric restriction in resistance trained lean athletes. International Journal of Sport Nutrition and Exercise Metabolism (2014). https://pubmed.ncbi.nlm.nih.gov/24092765/