Which protein powder is best for women?
The same plain whey or soy powder men use. No type of protein is made just for women. UK women eat about 67 g a day, over the 45 g guide. Check one number first.
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What is the best protein powder for women?
A plain whey powder, or soy if milk doesn’t suit you. A tub sold for women holds the same proteins as one sold for men.
Whey seems to be the most studied powder for weight training. It’s also quick to digest and mixes easily. In 9 trials, soy gave similar gains in strength and muscle to whey and other animal proteins, in people doing weight training.
| Powder | What trials found | Suits you if |
|---|---|---|
| Whey | Seems the most studied for weight training. Digests fast. | Milk suits you. |
| Casein | Digests slowly. In men, 30 to 40 g before bed raised overnight muscle building. | You want a shake at night. |
| Soy | Similar strength and muscle gains to whey in 9 trials. | You avoid milk. |
| Pea, rice or hemp | Research is limited so far. | You avoid milk and soy. |
Sources: ISSN; Messina 2018
Do women respond differently? A review of 49 trials saw no clear difference between men and women. Its authors add that far fewer trials have looked at women.
So ignore the “for women” label and pick by what you eat: whey if milk suits you, soy if it doesn’t.
Do women need protein powder?
Check the number that matters most: how much protein you eat now.
The UK guide for adults is 0.75 g per kg of body weight a day. For a 60 kg woman that’s 45 g. On average, UK women eat about 67 g.
So the British Nutrition Foundation says most of us don’t need protein supplements. If you train hard with a busy week, a shake can be a handy top-up. Food is still the better first choice.
Do you need a scoop? Four quick checks
- 1
Add up a day
Check food labels for grams of protein.
- 2
Compare
UK guide: 0.75 g per kg. At 60 kg, that’s 45 g.
- 3
Lift weights?
In trials, extra muscle levelled off at about 1.6 g per kg.
- 4
Still short?
One scoop of 20 to 40 g can close the gap.
Sources: BNF; Morton 2018; ISSN
Think of a fuel tank. Once it’s full, more fuel won’t make the car go faster.
Past about 1.6 g per kg a day, food and shakes together, the 49-trial review found no extra muscle on average in people lifting weights. If you already eat that much, a scoop won’t add muscle.
Working out your own number? See how much protein a day and protein to build muscle.
How much protein should a scoop have?
The International Society of Sports Nutrition (ISSN) suggests 0.25 g of protein per kg of body weight per dose, or 20 to 40 g. Space doses 3 to 4 hours apart.
At 60 kg, 0.25 g per kg is 15 g. That’s their advice for people who train, not a UK guideline.
- Below 20 gBelow 20 g. May match 0.25 g per kg if you’re under 80 kg.
- 20 up to 40 gISSN dose for one serving.
- Above 40 gAbove the ISSN range.
Source: ISSN
A tub with 15 g a scoop can be one ISSN dose if you weigh about 60 kg. If you’re heavier, plan for more. Compare the price per 20 g of protein, not per tub.
Will it help you get stronger? Trials in women alone found no clear gain in maximum strength from extra protein. The ISSN calls the effect in men and women small to modest.
The training does the most work, so see weight training for women.
Is whey protein OK for women, including in pregnancy?
Yes, unless milk is a problem. Whey comes from milk, and cows’ milk is one of the most common food allergies. Soy and peas are on that list too.
Bloated or loose after milk? You may react to lactose, the sugar in milk. See dairy-free protein powder for options.
Pregnant? The UK guide adds 6 g of protein a day. Breastfeeding adds 11 g while your baby is 0 to 6 months, then 8 g.
Some fitness supplements contain caffeine. In pregnancy, the NHS says to have no more than 200 mg of caffeine a day.
Over 50? The guide rises to 46.5 g a day, and older adults may need more. See protein after 40.
What to look for on the label
Five checks before you buy a protein powder
- Check the grams of protein per scoop. Look for 20 to 40 g, or 0.25 g per kg of your weight.
- Read the first ingredient. It should be the protein itself, such as whey, soy or pea.
- Pregnant? Check the ingredients for caffeine, and have no more than 200 mg a day in total.
- Expect “Excessive consumption may cause a laxative effect” if over 10% of the powder is polyols, a type of sweetener.
- Compete in a drug-tested sport? Only use batch-tested products, and check the batch number. UKAD says there’s no promise any supplement is free of banned substances.
Sources: GOV.UK: warnings; ISSN; NHS: pregnancy; UKAD
Words like “lean”, “slim” or “for her” don’t change the protein inside. Turn the tub round and judge it on these five lines.
Worried about heavy metals or organic claims? See which protein powder is cleanest.
When to speak to a GP
Speak to a GP if:
- You have kidney disease. The ISSN says people with kidney failure do better on less protein, so ask your kidney team first. A kidney dietitian explains the risks.
- You think you may have a food allergy, such as to milk or soy.
- You have symptoms of lactose intolerance that keep coming back and often happen after eating.
- You have lactose symptoms and you’ve had changes in your poo, bloating or blood in your poo for 3 weeks, or you’re losing weight without trying.
Call 999 if you have signs of a serious allergic reaction:
- your lips, mouth, throat or tongue suddenly swell
- you’re breathing very fast or struggling to breathe
- your throat feels tight or you’re struggling to swallow
- your skin, tongue or lips turn blue, grey or pale
- you suddenly feel very confused, drowsy or dizzy
- someone faints and can’t be woken
For kidney results, see kidney function tests. Taking creatine too? See creatine for women.