Protein is everywhere in nutrition advice — on supplement labels, in diet plans, and all over social media. Some people say 100 grams a day is the magic number. Others insist you need far less. The truth is simpler and more personal: your protein need depends mainly on your body weight, your activity level, and your age. This guide will help you calculate your own target without any guesswork.
Why Protein Matters
Protein is the building material of your body. It repairs muscle after exercise, builds enzymes and hormones, supports your immune system, and keeps you feeling full after meals. Unlike fat and carbohydrate, your body does not store protein in a reserve tank, so you need a steady supply from food every day. Too little over time can mean slower recovery, loss of muscle, and constant hunger. Too much, on the other hand, is usually just unnecessary — and it can crowd out other important foods.
The Baseline: The RDA
The Recommended Dietary Allowance (RDA) for protein is 0.8 grams per kilogram of body weight per day for sedentary adults. That is the minimum needed to avoid deficiency, not the amount for best results. For a 70 kg (about 154 lb) adult, that works out to roughly 56 grams per day. For a 90 kg (about 198 lb) adult, it is about 72 grams. To find your weight in kilograms, divide your weight in pounds by 2.2.
Think of the RDA as the floor, not the ceiling. Most people who exercise regularly, are trying to lose weight, or are over 65 benefit from eating more than this minimum.
Your Target by Activity and Age
If you are lightly active or sedentary
Aim for 1.0–1.2 grams per kilogram per day. For a 70 kg person, that is 70–84 grams. This range covers everyday life, light walking, and general health well.
If you exercise regularly or lift weights
Aim for 1.2–2.0 grams per kilogram per day. Sports nutrition guidance commonly supports 1.4–2.0 grams per kilogram for active people. For a 70 kg person training several times a week, that is roughly 98–140 grams per day. More than about 2.2 grams per kilogram offers little extra benefit for most people.
If you are losing weight
Aim for the higher end — around 1.6–2.2 grams per kilogram of body weight. When you eat fewer calories, your body is more likely to break down muscle along with fat. Extra protein, combined with strength training, helps protect your muscle so most of what you lose is fat.
If you are over 65
Aim for 1.0–1.2 grams per kilogram per day, spread across your meals. Ageing muscle responds less strongly to protein, so older adults need a bit more per meal — roughly 25–30 grams — plus resistance exercise to maintain strength and independence.
How to Hit Your Number Without Supplements
Most people can reach their target with ordinary food. Spread protein across three or four meals rather than loading it all into dinner — your body uses it better that way. A practical day for a 70 kg active adult might look like this: eggs or Greek yogurt at breakfast (15–20 g), chicken, fish, lentils, or tofu at lunch (30–40 g), a snack of cottage cheese or a handful of nuts (10–15 g), and a similar protein portion at dinner (30–40 g).
Good sources include eggs, chicken, turkey, fish, Greek yogurt, cottage cheese, milk, lentils, chickpeas, beans, tofu, tempeh, quinoa, nuts, and seeds. Animal foods tend to be higher in protein per serving, but plant sources work perfectly well when you eat a variety of them across the day.
Common Mistakes to Avoid
Skipping protein at breakfast. A breakfast of only toast or cereal leaves you short all day and often leads to evening snacking. Copying someone else's number. A 100-gram target is generous for a small sedentary person and modest for a large athlete — your weight decides your number. Ignoring total calories. Protein helps, but it cannot cancel out a large calorie surplus. Assuming you need powder. Supplements are convenient, not essential; real food usually wins on nutrition and satisfaction.
The Bottom Line
Start with your weight in kilograms, multiply by the factor that matches your life — 1.0–1.2 if you are lightly active, 1.4–2.0 if you train hard, 1.0–1.2 if you are over 65 — and spread the result across your meals. That is your personal protein target: no trends, no guesswork, just a number that fits your body.
Disclaimer: This article is for general information only and is not medical advice. People with kidney disease or other medical conditions should follow their doctor's or dietitian's guidance on protein intake.