Is whey protein vegetarian?
Yes, unless the cheese used animal rennet. Whey is left over from making cheese, so look for a vegetarian label. Skip dairy? One plant powder matched animal protein across 9 trials.
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Is whey protein vegetarian?
Usually, but it depends on the cheese. Whey is the liquid left over when milk is set into cheese. That setting step is mostly done with rennet.
Rennet can come from an animal’s stomach lining or from a fungus. The Vegetarian Society says animal rennet is not vegetarian. Fungus and thistle rennets are.
Think of rennet as a tool in the kitchen. The Vegetarian Society goes by how a food was made, so anything made with the aid of animal rennet fails its test.
| Powder | Vegetarian? | Why |
|---|---|---|
| Whey | Only if no animal rennet | Left over from cheese-making. |
| Casein | Check the label | A milk protein. Some is made with rennet. |
| Egg white | Yes | From eggs, not from slaughter. The Vegetarian Society logo needs free-range eggs. |
| Pea, soy or rice | Yes | Made from plants. |
| Beef protein | No | Made from meat. |
| Bone broth protein | No | Made from bone stock. |
Sources: Whey review; Vegetarian Society
So before you buy whey, check the tub says it’s vegetarian.
How do I find a vegetarian protein powder?
Start with the logo. The Vegetarian Society’s mark can’t go on a product made with animal rennet, gelatine or bone stock.
Five checks before you buy a vegetarian shake
- Look for “suitable for vegetarians” or the Vegetarian Society Approved logo on the tub.
- No label on a whey powder? Ask the maker if the cheese was set with animal rennet.
- Scan the ingredients for gelatine, which is not vegetarian.
- Skip beef protein and bone broth powders.
- Read the allergens in bold, such as milk, eggs and soya.
Sources: Vegetarian Society; GOV.UK: allergens
Asking a maker? Animal rennet may also be called “traditional rennet”, “pepsin” or “animal enzymes”.
UK law says allergens must be highlighted in the ingredients. So milk in a plant shake stands out. For other label checks, see which protein powder is cleanest.
Are plant protein shakes as good as whey?
Close, in the trials so far. A review of 9 trials covered 6 weeks or more of lifting weights. Soy gave similar gains in muscle and strength to whey or other animal protein.
Pea matched whey in one 12-week trial of 161 young men, run partly by a pea protein maker. Rice matched it in one 8-week trial of seasoned lifters. Sports experts call this research “limited” so far.
In short lab tests, whey switches on muscle building more than soy.
A second review of 16 trials found no overall difference in lean mass or strength. But adults under 50 gained about 0.41 kg more lean mass, the parts of you that aren’t fat, on animal protein.
- Below 20 g per scoopLess than the usual dose.
- 20 up to 40 g per scoopISSN: 20 to 40 g per dose.
- Above 40 g per scoopMore than the usual dose.
Source: ISSN
Eat dairy? Vegetarian whey has the most research. If not, try soy, then pea, and see dairy-free protein powders.
Do vegetarians need protein shakes?
Most don’t. UK protein intakes are above the advised amount on average, “including in vegetarians and vegans”. The NHS says most vegetarians usually have enough protein.
Do you need a shake?
- 1
Know your need
Adults need 0.75 g per kg a day. That’s 45 g for women and 56 g for men.
- 2
Count your food
Eggs, dairy, beans, lentils and tofu all add up.
- 3
Training hard and busy?
A shake can be a handy top-up.
- 4
Food first
Get protein from food where you can.
Source: BNF
Even on an intensive exercise plan, the BNF says you can still get enough from food. You don’t need to pair beans and grains at every meal. A mix of plant foods over the day is enough, as long as you eat enough food overall.
What vegetarians do need to watch, says the NHS, is iron and vitamin B12.
Find your number with how much protein you need a day, then try these high protein vegetarian meals.
When to speak to a GP
Book an appointment if:
- You think you or your child may have a food allergy. Milk, eggs, soybeans and peas are among the most common.
- You have signs of lactose intolerance, like bloating after dairy, and they keep coming back after eating.
- You have signs of lactose intolerance and have had poo changes that aren’t usual for you, blood in your poo, or bloating and discomfort for 3 weeks, or you’re losing weight without trying.
- You’ve been told to limit protein for kidney problems. Ask your kidney team before using a powder, as kidney failure can need less protein.
Call 999 if lips, mouth, throat or tongue suddenly swell, or you’re breathing very fast or struggling to breathe. The same goes if your throat feels tight or you’re struggling to swallow.
Also call 999 if skin, tongue or lips turn blue, grey or pale, or someone gets suddenly confused, drowsy or dizzy. The same goes if someone faints and can’t be woken, or a child is limp, floppy or not responding.
Taking whey and worried about results? See whey protein and blood tests.