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    Ingredient evidence

    Protein

    Not a supplement so much as a nutrient most women under-eat, particularly in the decade where under-eating it costs the most.

    Also sold as: whey protein, plant protein, protein powder.

    Our read of the evidence

    Good evidence

    Multiple decent human trials point the same way.

    The highest-value thing in this whole library, and the least exciting. Food first, powder for convenience.

    Why the requirement changes with age

    Muscle mass declines from the fourth decade onwards, and the rate accelerates around menopause as oestrogen falls. Muscle is not cosmetic: it underpins metabolic health, glucose handling, bone loading and the ability to stay independent later. Losing it quietly is one of the biggest avoidable health costs of midlife.

    Older muscle responds less efficiently to protein, which means intake needs to be higher, not lower, to produce the same effect. Most guidance for active adults over 50 lands around 1.2-1.6g per kilogram of body weight daily, spread across meals rather than loaded into one.

    The intervention that actually builds muscle is resistance training. Protein is the raw material; training is the signal. Neither works well without the other.

    Do you need a powder?

    No. Eggs, dairy, fish, meat, tofu, beans and lentils will get most people there. Powder solves a practical problem: hitting 25-30g at breakfast, which is the meal where UK women are most often short.

    Whey is the best-studied and highest in leucine, the amino acid that most strongly triggers muscle protein synthesis. Soy and pea blends are close enough for practical purposes if you avoid dairy. Collagen is not a suitable primary protein source because it lacks tryptophan.

    Ignore products marketed specifically to women at a premium. The physiology is the same; the difference is usually the packaging, a smaller scoop and a higher price per gram of protein. Compare cost per 20g of protein and buy on that.

    How to take it.

    Typical dose
    1.2-1.6g per kg body weight daily for active adults over 40
    Form
    Food first; whey, soy or pea isolate powder for convenience
    Timing
    Spread across meals, 25-30g per meal
    Worth knowing
    People with kidney disease should take individual advice before increasing protein intake substantially.

    What it will not do.

    • It will not build muscle without resistance training
    • It will not cause bulk or bulkiness - that is not how it works
    • It will not make up for very low overall energy intake

    Who should avoid it.

    • You have significant kidney disease, without dietetic advice
    • You have a dairy allergy and the product is whey-based

    Raise with a prescriber

    • No significant medicine interactions

    Products containing protein.

    Everything below is stocked in the UK. Compare on the active dose and the cost per day rather than the size of the pack.

    Products containing Protein
    ProductKey activesFormPricePer dayBest for
    Nourishing ProteinWelleCoPlant protein blendPowder£75£2.50Protein intake in perimenopause and beyond, Strength training recovery, Vegan diets
    The HydroProtein ElixirWelleCoHydrolysed proteinPowder£39£1.30Longer or hotter training sessions, Night sweats and fluid loss, Anyone who dislikes thick shakes
    DR.VEGAN Creatine & BCAADR.VEGANCreatine monohydrate, BCAAsPowder£32.99-Strength training, Protecting muscle in midlife, Hitting protein targets around training
    DR.VEGAN Protein & Creatine SuperblendDR.VEGANPlant protein, Creatine monohydratePowder£36.99-Hitting protein targets around training, Strength training, Protecting muscle in midlife
    Igennus Advanced Hydrolysed Collagen PeptidesIgennus Healthcare NutritionBovine collagen peptidesPowder£28.9572pAdding protein simply, Joint comfort alongside strength work, Hitting protein targets around training

    Prices are the brand's UK list price at the time of writing and change often. Cost per day is calculated from pack size and the label's daily serving, and is shown only where both are published.

    Common questions.

    How much protein should a woman eat a day?

    The UK minimum is 0.75g per kilogram of body weight, but around 1.2-1.6g per kilogram better supports muscle in active adults, particularly over 40.

    Is protein powder necessary?

    No. It is convenience. If you are hitting your intake from food, a powder adds nothing except an easier breakfast.

    Is whey or plant protein better?

    Whey is higher in leucine and slightly more effective gram for gram, but a good soy or pea blend at a slightly higher dose does the job.

    A supplement is not clinical care.

    If symptoms are affecting your work, your sleep or your relationships, the useful next step is an assessment rather than another purchase. Our check-in takes three minutes and points you to the right kind of clinician.

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    Food supplements are not medicines and are not intended to diagnose, treat or cure any condition. They should not replace a varied diet or prescribed treatment. If you are pregnant, breastfeeding, taking medication or managing a diagnosed condition, check with a pharmacist or clinician before starting anything on this page. We do not accept payment for inclusion or placement. Where a link earns us a commission we say so on the product page. Last reviewed 27 August 2026.