Can You Take Collagen With Protein Powder?

Quick answer

A 3-week trial in 22 fit men gave 20 g of collagen peptides plus 25 g of whey and found the same recovery as 45 g of whey alone. Collagen lacks tryptophan, so it is not a complete protein, and in older women whey raised muscle protein building more than collagen.^1,2,3

Key facts

Collagen lacks tryptophan, counts as an incomplete protein, and scores zero on the standard protein-quality scale.^2,4
In 22 fit men, swapping part of the whey for collagen peptides changed neither muscle damage markers nor recovery of strength over 3 weeks of training.¹
In 22 older women taking 30 g twice a day for 6 days, whey raised muscle protein building more than collagen, and collagen's longer-term rise was not significant.³
The ISSN suggests 1.4 to 2.0 g of protein per kg of body weight a day for most people who exercise, and NIH reports no safety concerns up to about 2.0 g per kg.^5,6
Essential amino acids peaked in the blood about 30 to 50 minutes after 20 g of either collagen or dairy protein, with a higher glycine peak from collagen and a higher leucine peak from dairy.⁷

The question behind the question

People who ask this usually want to know two things. Does collagen count toward the protein they are trying to eat each day, and does adding it get in the way of a protein powder they already use? The research answers the first better than the second, and the answer to the first is only partly.

Collagen lacks tryptophan, one of the nine essential amino acids, so it counts as an incomplete protein and scores zero on the standard protein-quality scale. In head-to-head tests, whey raised muscle protein building more than collagen.^2,4

In practice that means collagen grams and complete-protein grams are not interchangeable. A modeling study found that collagen peptides could supply as much as 36% of daily protein in a typical Western diet while essential amino acid needs are still met, but it is a calculation, and one author does research for a supplement maker.²

What the studies compared

Three studies that put collagen and protein in the same comparison^1,3,8
Study	Who	Amounts	What it found
Robberechts 2024	22 fit young men, 3 weeks of eccentric training	20 g collagen peptides plus 25 g whey, against 45 g whey	No difference in muscle damage markers or recovery of strength
Oikawa 2020	22 healthy women aged about 69, 6 days with exercise	30 g of whey or of collagen protein, twice a day	Whey raised muscle protein building more than collagen, at rest and after exercise
Wageh 2021	26 young adults, 10 weeks of training	A mix with 20 g whey, 2 g leucine and 2.5 g creatine against 20 g collagen peptides, each twice a day	Lean mass rose 4.1 kg with the mix and 2.8 kg with collagen; the many differences mean it cannot isolate one ingredient

Notice what none of them did. No trial in this table tested whether collagen changes how much of a protein powder is absorbed, and no source reports that it does.

Where the graded evidence points

Extra protein supports small added gains in strength and lean mass from resistance training when your usual intake is below about 1.6 g per kg of body weight a day*⁹

Moderate evidence

A meta-analysis of 49 randomized trials (1,863 people) found protein supplements added about 2.5 kg to one-rep-max strength and 0.3 kg of fat-free mass over training alone, with no further gain above about 1.6 g of protein per kg a day in total. The trials averaged 36 g of supplement a day (range 4 to 106 g) and mostly used whey or milk protein, so 20 or 21 g of a fava and yeast blend is only a partial match; hence moderate, not strong.

Amount studied: 4 to 106 g of supplemental protein a day (36 g on average) during 6 to 52 weeks of resistance training

Alongside resistance training, may support tendon adaptation*^10,11

Early evidence

A 2024 meta-analysis of collagen peptides taken with training (19 trials, 768 healthy adults) pooled four small trials that measured tendons (114 people; 5, 15 or 30 g a day) and found larger gains in tendon size but no difference in tendon stiffness; the authors rated this evidence as very low certainty. In a 2025 study, 30 g of collagen after exercise did not speed up connective tissue protein building in muscle.

Amount studied: 5, 15 or 30 g a day with training; most training trials used 15 g

The first claim depends on total daily protein, so grams from collagen do not obviously count toward it. The second is the only graded collagen claim that involves training, and it rests on four small tendon trials rated very low certainty.^9,10

Counting grams without double counting

Take a person weighing 70 kg who aims for 1.6 g of protein per kg. That is 112 g of protein a day. A 20 g serving of collagen peptides, the amount used in the combined trial, would amount to roughly 18% of that figure if all 20 g counted as protein, and less than that once protein quality is considered, since collagen scores zero on the standard scale.^1,4,5,9

The ISSN also suggests spreading protein over the day in servings of 20 to 40 g every 3 to 4 hours, with 0.7 to 3 g of leucine per serving. Collagen gave a lower leucine peak in the blood than dairy protein did in a direct comparison.^5,7

What the research says for women

Far fewer protein trials have been done in women than in men. A pooled analysis that included 14 groups of women found no clear difference between the sexes, while the ISSN notes that women-only trials have not shown statistically significant gains in maximal strength.^5,9

In women aged 55 and over, whey protein combined with resistance training raised arm strength and leg lean mass more than placebo; without training it made no difference.¹²

Collagen's skin trials run the other way: 21 of 26 in a 2023 analysis enrolled only women. So a woman reading both sets of research is reading protein studies that include few women and collagen studies that include few men, and neither tested the two together.¹³

Cautions and who should ask first

High-protein diets of two to three times the RDA do not appear to harm kidney function, bone health or hydration in healthy people, and trained adults eating up to about 3.3 g per kg a day for up to a year showed no change in kidney or liver markers. People with severely reduced kidney function may need to limit protein.^5,6,14

Allergic reactions can occur. Milk, soy and peanuts are major food allergens, and peas, lentils, lupin and other legumes can also cause reactions, sometimes severe and sometimes in people already allergic to peanut.^15,16

Fish collagen is a concern for people allergic to fish, a major food allergen that labels must name. Some people with alpha-gal syndrome, a red meat allergy usually caused by tick bites, also react to gelatin and other products made from mammals.^17,18

Ask your pharmacist or doctor first

Protein can lower how much levodopa is absorbed. The carbidopa and levodopa label says levodopa competes with certain amino acids to cross the gut wall, so a high-protein diet may delay its absorption and reduce the amount that reaches the blood.¹⁹

On the medicine's label

Ask first if you have kidney disease, have had kidney stones or have been told to limit protein.^6,20
Ask first if you are pregnant or nursing, or under 18.⁶
Ask first if you take levodopa or an MAO inhibitor.^19,21
Do not use a fava bean protein if you have G6PD deficiency, unless your doctor advises it.²²

What is in our products

Our products show their protein on the label. The overlap check compares our collagen with our plant protein, and then our two collagen powders with each other.

Our Collagen Peptides with our Plant Protein

Taken as their labels direct, their amounts do not overlap.

Our Collagen Peptides with our Collagen Peptides

Both collagen powders supply 20 g of collagen per serving. Taking both gives 40 g a day, more than any trial we reviewed. Choose one per day.

What’s in ours

Collagen Peptides: Protein, 18 g per serving, from the label
Collagen Peptides: Protein, 18 g per serving, from the label
Plant Protein: Protein, 20 g per serving, from the label
Plant Protein: Protein, 21 g per serving, from the label

What’s in ours

Collagen Peptides: Hydrolyzed Collagen Peptides, 20 g per serving, from the label
Collagen Peptides: Hydrolyzed Collagen Peptides, 20 g per serving, from the label

Questions people ask

Should collagen replace my protein powder?

Not on the evidence we read. Collagen scores zero on the protein-quality scale because it lacks tryptophan, and whey raised muscle protein building more than collagen in older women and in head-to-head tests.^3,4

Can I put collagen in my protein shake?

A trial that replaced part of a whey dose with 20 g of collagen found no difference from whey alone. No source we read compares mixing them in one shake with taking them separately.¹

Is there research on protein powder with collagen in women?

The trial that put them together was in men. Far fewer protein trials have been done in women than in men, and the older-women trial we read compared whey with collagen rather than combining them.^3,5

Is there a limit on how much protein I can add?

No upper limit has been set for protein. NIH advises caution with high intakes from foods and supplements together and reports no safety concerns up to about 2.0 g per kg a day. Ask first if you have kidney disease or have been told to limit protein.⁶

See what we make

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See the Full Measure line Collagen Peptides Collagen Peptides Plant Protein

Sources

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

This page is information, not medical advice. Talk to your doctor or pharmacist about your own situation.