Protein and weight loss: how much do you really need?

Of all the nutrition advice you’ll hear while trying to lose weight, “eat more protein” is one of the few things doctors and dietitians almost always agree on. Agreement doesn’t make it obvious, though. How much is enough? Is more always better? And does it matter if you’re already eating less overall?

It matters more than the number on the scale suggests. Protein shapes what kind of weight you lose, not only how much. Do the kilos coming off come from fat, or from the muscle you’d rather keep? That’s the part protein has a say in. Let’s make it practical.

Why protein earns its place in weight loss

When you eat in a calorie deficit, your body has to find that missing energy somewhere. Protein’s job is to steer it toward your fat stores and away from your muscle. It does a few useful things at once.

It protects the muscle you don’t want to lose

Losing weight always means losing some tissue. The goal is for most of it to be fat. When protein runs too low, the body dips into muscle for fuel, and that’s a poor trade. Muscle keeps you strong and steadies your blood sugar, and it quietly burns energy all day. Protecting it is one of the best reasons to put protein first, and it works even better paired with some resistance work, as we cover in our beginner’s guide to strength training.

It keeps you fuller for longer

Gram for gram, protein is the most satisfying nutrient on your plate. It calms appetite hormones and blunts the hunger that tends to derail good intentions by mid-afternoon. A breakfast of eggs and beans carries you further than a bowl of sweetened cereal. That’s why a higher-protein plate makes a calorie deficit easier to hold.

It costs your body more to digest

Your body burns a slice of the energy in every meal just processing it, and protein carries the highest “tax” of the three main nutrients. The effect is modest, so it’s no licence to eat freely. Even so, a higher-protein diet nudges your daily burn in a helpful direction, for free.

Protein doesn’t decide whether you lose weight. Your overall calories do that. What protein decides is how much of what you lose is fat, and how much of your comfort and strength you keep along the way.

So how much do you need?

The amount that keeps you clear of a deficiency is not the same as the amount that supports weight loss. When you’re eating less overall, your protein needs go up, not down. You’re asking your body to hold onto muscle on fewer calories.

As a practical starting point, somewhere around 1.2 to 1.6 grams of protein per kilogram of body weight per day serves most people well during weight loss. For a rough sense of scale:

• Around 70 kg works out to roughly 85 to 110 g of protein a day.
• Around 90 kg lands nearer 110 to 145 g.

Two caveats worth flagging. If you’re carrying a lot of excess weight, base the sum on a healthier goal weight rather than your current one, so the target stays realistic. And if you have kidney concerns or any chronic condition, set your protein target with your doctor. Treat everything here as general guidance rather than a personal prescription. A clinician or registered dietitian can tailor the number to you, and it fits alongside working out how many calories you need overall.

How to actually hit your target

Numbers are easy to write and harder to eat. The trick is spreading protein across the day, roughly 25 to 40 grams per meal, rather than piling it all into supper. Here’s what that looks like with everyday South African foods:

• Eggs: about 6 g each, so two or three make a solid breakfast base.
• Chicken breast: a palm-sized portion delivers roughly 30 g.
• Lean beef or ostrich mince: a small serving lands around 25 to 30 g.
• Tinned pilchards or tuna: affordable, shelf-stable, roughly 20 to 25 g a tin.
• Maas, plain yoghurt and cottage cheese: easy 10 to 20 g add-ons.
• Beans, lentils and soya mince: budget-friendly plant options that also bring fibre.
• Biltong: a concentrated, portable top-up for when you’re short.

You don’t need to weigh everything on a scale for the rest of your life. Get a protein source onto every plate, then build the rest of the meal around vegetables and smart carbs. That does most of the work on its own. We break the framework down further in building a plate that keeps you full for longer.

Common protein mistakes to sidestep

• Back-loading it all to dinner. A protein-light breakfast and lunch leaves you hungry and grazing by 3pm. Spread it out.
• Assuming more is always better. Past a sensible target, extra protein adds little and just crowds out other foods. The calories still count.
• Leaning on sugary “high-protein” products. Some bars and flavoured drinks smuggle in a lot of sugar. Whole foods first; check the label on the rest.
• Forgetting fibre and vegetables. Protein is a lever, not the whole machine. Balance keeps you fuller and your gut happier.

A note if you’re on a medically supervised programme

If you’re losing weight with the support of doctor-led options that reduce appetite, protein matters more, not less. When you’re eating far less than usual, it’s easy to fall short without noticing, and that’s exactly when muscle is most at risk. Make the smaller amount you do eat count by leading with protein at each meal. A good programme keeps an eye on this for you. If you’d like to see how that ongoing support works, our how it works page walks through it.

The short version

Protein won’t melt fat on its own. No single food does. What it does is make almost everything else about weight loss easier. It curbs hunger and guards your strength, and it tilts the weight you lose toward fat rather than muscle. So set a sensible target and spread it across your day. Build each plate around a real protein source, and check the specifics with a clinician who knows your history. It’s one of the highest-return habits going, and you can start at your next meal.