How much protein do I need? Targets by age and goal

By the DieticiansWorldwide.com editorial team · 17 October 2026 · Weight management & GLP-1

The baseline: what official guidelines say

Every major authority sets a protein figure for healthy adults, and they are remarkably close. The differences come from rounding, the data each committee used and how they define "enough".

• United States and Canada: the Recommended Dietary Allowance (RDA) for adults 19 and over is 0.80 g per kg of body weight a day, which works out at 56 g for a reference man and 46 g for a reference woman. Protein should provide between 10% and 35% of energy (Health Canada, Dietary Reference Intakes).
• European Union: the European Food Safety Authority set a Population Reference Intake of 0.83 g per kg a day for adults, including older adults, in 2012 (EFSA).
• United Kingdom: the Reference Nutrient Intake is 0.75 g per kg a day, set by the government's advisory committee in 1991. A 60 kg adult therefore needs 45 g and a 74 kg adult 55.5 g. The "reference intake" printed on UK food labels is 50 g (British Nutrition Foundation, nutrition requirements).

These are not minimums for survival or ideal targets for muscle. They are set to cover the needs of nearly all healthy people who are not trying to change their body composition. EFSA reports that average adult intakes in Europe are often at or above its reference figure, at 67 to 114 g a day for men and 59 to 102 g for women.

So, how much protein do you need in a day? If you are a healthy adult under 65 who is not trying to build muscle or lose weight, 0.75 to 0.83 g per kg covers you, and you probably already eat that much.

How to work out your own number

Multiply your weight in kilograms by the target for your situation.

The protein calculator linked at the end of this guide does the arithmetic for you. Two adjustments are worth knowing:

1. If you carry a lot of body fat, multiplying your full weight by a high target overestimates what you need, because fat tissue uses little protein. The 2025 GLP-1 advisory notes that a target based on lean mass, 1.5 g per kg of fat-free mass, is more accurate when body composition is known. Without a scan, ask a dietitian which weight to base your target on.
2. Energy matters too. Protein is used to build and repair tissue only when you eat enough overall. Check your energy needs with our calorie calculator.

Protein for older adults

The biggest argument about protein concerns people over 65. Muscle becomes less responsive to protein with age, and illness speeds muscle loss.

The most quoted target comes from an international expert panel set up by the European Union Geriatric Medicine Society. Its 2013 PROT-AGE paper advises an average of 1.0 to 1.2 g per kg daily for over-65s in general, rising to at least 1.2 g per kg for those who are active and to 1.2 to 1.5 g per kg for the many older people living with an acute or long-term illness. The panel excluded one group from these higher figures: older people whose kidney function is severely reduced (an eGFR below 30) and who are not yet on dialysis (Bauer and colleagues, PROT-AGE position paper, 2013).

Official reference values have not moved: EFSA's 0.83 g per kg applies to older adults too. The two positions answer different questions. Reference values aim to prevent deficiency in healthy people; PROT-AGE aims to help older people keep muscle and function. For an older person who is eating less, losing weight or recovering from illness, the higher figure is the more useful target.

Protein works best with movement. The PROT-AGE group recommends both endurance and resistance exercise at levels that are safe for the individual. If you or a parent are finding stairs, chairs or carrying shopping harder, our guide to sarcopenia explains how muscle loss is assessed and treated.

Protein for building muscle and for athletes

If you train with weights or play sport, you need more than the reference figure, but probably less than gym culture suggests.

The International Society of Sports Nutrition (ISSN) says that 1.4 to 2.0 g per kg a day "is sufficient for most exercising individuals" for building and maintaining muscle (Jäger and colleagues, ISSN protein position stand, 2017). How much extra muscle does that buy? A 2018 meta-analysis that pooled 49 trials found that protein supplements added an average of 0.30 kg of fat-free mass over training alone, and intakes above about 1.6 g per kg a day gave no further gain in fat-free mass (Morton and colleagues, British Journal of Sports Medicine, 2018).

Read together, these suggest a practical range of about 1.4 to 1.6 g per kg for most people who lift, with little extra muscle to be gained above that. Higher intakes are used by some athletes cutting weight: the ISSN says 2.3 to 3.1 g per kg may be needed to keep lean mass in resistance-trained people eating in an energy deficit. Those figures are for trained athletes under supervision, not a general target.

Supplements that support muscle are not substitutes for protein. Creatine, for example, supplies no protein and does not reduce your needs; our guide to creatine monohydrate explains what it does.

Protein when losing weight and on GLP-1 medicines

When you eat less, a share of the weight you lose comes from lean tissue. Protein and resistance training are the two tools with the best evidence for limiting that.

Because GLP-1 medicines such as semaglutide and tirzepatide blunt hunger, eating enough protein can become a daily struggle. Guidance written jointly in 2025 by four US lifestyle, nutrition and obesity societies points out that, while the general RDA is 0.8 g per kg, "higher targets, such as 1.2-1.6 g/kg/d, have also been proposed during active weight reduction", or an absolute target of 80 to 120 g a day (Mozaffarian and colleagues, American Journal of Clinical Nutrition, 2025). It also reports that in the STEP 1 trial of semaglutide, about 38% of the weight lost was lean body mass, and recommends strength training at least three times a week.

Is the protein boom overdone?

Partly. There are two honest positions:

• For most healthy adults under 65, the evidence that eating far above the reference intake improves health is weak. If you eat a varied diet, you probably meet your needs already, and high-protein bars, cereals and drinks add cost more than benefit.
• For specific groups, the case for more is strong: older adults, people who are ill or recovering, people losing weight, especially quickly or on medicines, and people training to build muscle.

So the boom is overdone as a message for everyone, and underdone for the groups who need it most, who are often eating too little rather than too much. Our guides to GLP-1 weight loss and to whether creatine helps with weight loss cover muscle protection during weight loss in more detail.

Pregnancy, breastfeeding and children

Needs rise in the second half of pregnancy. The North American RDA rises to 1.1 g per kg a day, or 71 g for the reference woman, in the second half of pregnancy, and to 1.3 g per kg during breastfeeding. EFSA instead adds fixed amounts on top of the adult figure: 1 g a day in the first trimester, 9 g in the second and 28 g in the third, and 19 g a day in the first six months of breastfeeding. The UK adds 6 g a day in pregnancy and 11 g a day in the first six months of breastfeeding.

Children need slightly more per kilogram than adults because they are growing. The North American RDA is 0.95 g per kg for ages 4 to 13 and 0.85 g per kg for ages 14 to 18, and EFSA's values for children and adolescents range from 0.83 to 1.31 g per kg depending on age. Protein powders and shakes are rarely needed for children unless a doctor or dietitian advises them.

When you may need less protein

Chronic kidney disease is the main exception to "more is fine". In 2020 the US National Kidney Foundation's KDOQI guideline, produced with the Academy of Nutrition and Dietetics, recommended 0.55 to 0.60 g per kg a day for metabolically stable adults with stage 3 to 5 kidney disease who are not on dialysis and do not have diabetes, and 0.6 to 0.8 g per kg for those with diabetes. People on dialysis usually need more, about 1.0 to 1.2 g per kg (International Society of Renal Nutrition and Metabolism commentary on KDOQI, 2021).

Other situations where you should get advice before following high-protein advice include liver disease and rare inherited conditions that affect how the body handles protein.

Is 100 g of protein too low?

It depends entirely on who you are. Here is what 100 g a day means at different body weights:

• 55 kg: about 1.8 g per kg, at the upper end of the athlete range.
• 70 kg: about 1.4 g per kg, enough for most people who lift weights.
• 90 kg: about 1.1 g per kg, comfortably above the reference intake and around the PROT-AGE target for older adults.
• 130 kg: about 0.77 g per kg of total weight, which may still be adequate for someone with a lot of body fat if their target is based on lean or adjusted weight.

For most adults, 100 g is not too low. It falls inside the 80 to 120 g absolute range mentioned in the 2025 GLP-1 advisory. It may be too low for a large, heavily training athlete, and it is too high for some people with kidney disease.

How to spread protein across the day

How you split your protein may matter almost as much as the total, especially for older adults and people who train. The ISSN suggests about 0.25 g of high-quality protein per kg of body weight per meal, or 20 to 40 g, every three to four hours. For a 70 kg person that is roughly 18 to 20 g, or more after training.

In practice:

• Breakfast is often the weak meal. Eggs, yoghurt, milk, beans or fish raise it more than toast or cereal alone.
• Include a protein food at every meal rather than relying on one large evening portion.
• Use snacks if appetite is small. Our high-protein snacks guide lists options with protein and fibre per serving.
• Mix plant and animal sources. Beans, lentils, tofu, nuts and seeds count, and combining different plant foods across the day covers the essential amino acids.
• Read the label for grams of protein per serving, not per 100 g, when comparing products.

What about protein powder?

People often ask which protein powders to buy. We do not recommend brands, but the principles are simple: a powder is a convenience, not a requirement. It is useful when appetite is low, as on GLP-1 medicines, when you train hard and cannot reach your target from food, or when you need a portable option. Look for a clear protein content per serving, a short ingredient list, and independent testing if you compete. Our protein powder guide covers whey versus plant proteins and recent testing for heavy metals.

When to get personal advice

General targets suit most people. A dietitian adds value when your situation is complicated: you are older and losing weight, you have kidney, liver or bowel disease, you take a GLP-1 medicine and cannot eat much, you are pregnant, or you are an athlete managing weight. For support with weight loss specifically, start at our weight management hub; otherwise you can book a session with a registered dietitian for a target that fits your health and goals.

Try the free protein calculator