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Protein · Answer
For healthy adults in South Africa, whey becomes too much only when total daily protein climbs well above about 2.0–2.2 g per kg or causes stomach trouble. ISSN guidance is 1.4–2.0 g/kg a day and benefits plateau near 1.6 g/kg, so most people need one or two scoops (about 25–50 g). With kidney disease, follow medical advice.
The question is really about total protein, not whey alone. The ISSN recommends 1.4–2.0 g of protein per kg of body weight a day for people who train. A meta-analysis of 49 trials found muscle benefits plateau near 1.6 g/kg a day (95% interval 1.03–2.20), with about 2.2 g/kg as a practical upper bound. Beyond that you pay for extra protein and risk digestive trouble without extra muscle. Short-term higher intakes up to 2.3–3.1 g/kg may help trained people keep lean mass while cutting.
| Body weight | Daily target at 1.4–2.0 g/kg | If food supplies 70% | Whey needed |
|---|---|---|---|
| 60 kg | 84–120 g | 59–84 g | about 25–36 g (one scoop) |
| 75 kg | 105–150 g | 74–105 g | about 31–45 g (one to two scoops) |
| 90 kg | 126–180 g | 88–126 g | about 38–54 g (up to two scoops) |
One scoop is typically 20–27 g of protein. A practical rule of ours: let powder supply no more than about a third of your protein and let food supply the rest. That is a guideline, not a regulatory limit.
Not for muscle. Trommelen and colleagues (2023) found 100 g of protein after exercise produced a longer anabolic response than 25 g. But large servings tend to cause bloating and loose stools, especially with concentrate, milk or sugar alcohols (why whey bloats).
Under-18s, pregnant women and anyone on medication should meet protein needs through food first and ask a professional before adding powder (can teenagers take whey).
Persistent diarrhoea, swelling or rash, dark urine, flank pain, or any liver or kidney diagnosis: stop and see a doctor. Take stock of total daily protein, not scoops, using how much protein per day. For a tub, see the best whey protein in South Africa.
Educational information, not medical advice. Speak to a doctor, pharmacist or registered dietitian before using supplements if you are pregnant or breastfeeding, under 18, taking medication, or living with kidney, liver or heart disease. Prices were observed in October 2026 and are not offers.