PhD Diet Whey
- Protein blend
- 68g
- Protein / 100g
- 17g
- Per 25g scoop
- 73p
- Per 25g protein
- £39.97
- 2000g pack
Our verdict
Scored on the label and the price, not on how it tastes.
- Genuinely low calorie per serving, at roughly 91 kcal for the 25g scoop
- 4.5g of fibre per 100g, which does help with satiety in a deficit
- Widely stocked in UK supermarkets and pharmacies, so it goes on offer often
- Pack sizes from 250g, so trying it is cheap
- CLA at roughly 500mg per serving against the 3 to 4g used in research
- L-carnitine at roughly 100mg against the 1 to 2g used in research
- Green tea extract at roughly 50mg
- The 25g scoop is smaller than the market norm, so per-serving protein looks lower than it is per 100g
Read the full verdict
Diet Whey is sold on its added ingredients, so those are worth looking at closely. The declared doses are far below the amounts used in the research the ingredients are known for: roughly 500mg of CLA against 3 to 4g in studies, 100mg of L-carnitine against 1 to 2g, and 50mg of green tea extract. Those are not doses that will do anything measurable. What you are actually buying is a 68g per 100g whey blend with fibre added, in a 25g scoop, at a price that usually sits above plainer products with more protein in them. It becomes reasonable value on offer, which is how most UK buyers we found describe buying it.
Where to buy PhD Nutrition Diet Whey
Ordered by cost per 25g of protein, because pack sizes and protein densities differ enough that a headline price on its own does not tell you which is better value.
| Retailer | Size | Price | Per 25g | |
|---|---|---|---|---|
| Amazon UK | 2000g | £39.97 | 73p | View deal |
How it scored
How we scoreFour categories, each out of 25, every one taken from the label or the live partner price.
68g per 100g
73p per 25g protein
3.6g sugar, 5.6g fat per 100g
none found
Nutrition
Taken from the manufacturer’s published label. Source.
PhD uses a 25g scoop, smaller than the 30g to 34g typical elsewhere, so its 17g per serving is not directly comparable to a rival’s 24g without adjusting for that.
| Nutrient | Per 100g | Per 25g |
|---|---|---|
| Protein | 68g | 17.0g |
| Energy | 365 kcal | 91 kcal |
| Carbohydrate | 8.4g | 2.1g |
| of which sugars | 3.6g | 0.9g |
| Fat | 5.6g | 1.4g |
| of which saturates | 2.4g | 0.6g |
| Fibre | 4.5g | 1.1g |
| Salt | 0.6g | 0.1g |
Ingredients and formulation
- 01Whey protein concentrate
- 02Milk protein
- 03Whey protein isolate
A diet whey rather than a straight whey: the protein blend is padded with fibre and a set of added active ingredients aimed at body composition. The protein density of 68g per 100g reflects that.
Sucralose
250g · 1kg · 2kg
Third-party testing
Certification is per programme and often per flavour or per batch, so a badge on one product does not carry across a brand’s whole range.
We found no Informed Sport listing for the standard retail Diet Whey.
Made by
PhD Nutrition, UK
Taste and what buyers report
Quoted and linked, so you can read the full thread.
“When made with milk it feels like drinking wet sand, and when made with water it is absolutely revolting.”
“I use the PhD diet whey, and have always found them to be quite nice with just water.”
“For smoothies I like the PhD Diet Whey in strawberry shortcake. Makes lovely berry smoothies.”
What the maker does not publish
- PhD Diet Whey has very little independent discussion online. The opinions above are the substantive ones we could find, and they contradict each other on texture.
- We compared declared doses against published research doses. We have not independently assayed the product.
Alternatives worth a look
Frequently asked questions
How much protein is in PhD Diet Whey?
17g in a 25g scoop, about 68g per 100g. Note the scoop is smaller than the 30g to 34g typical elsewhere, so compare on the per-100g figure.
Does the CLA and L-carnitine in PhD Diet Whey do anything?
Not at these doses. The declared amounts are roughly 500mg of CLA and 100mg of L-carnitine per serving, where the research showing any effect uses 3 to 4g and 1 to 2g respectively. They are present, but not in quantities that would produce a measurable result.
Is diet whey better than normal whey for weight loss?
Not inherently. Diet wheys are lower in protein per 100g than plain whey because the added ingredients and fibre take up space. What drives fat loss is total daily calories and protein intake, so a cheaper plain whey with more protein per pound often does the job better.
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Open the Protein FinderLast updated 19 August 2026