Collagen powders come from different animal sources and are sold in flavoured and unflavoured forms. A label may give the source, the amount per serving and the additional ingredients. Those are useful facts to compare; none alone proves a particular product will improve your skin or joints.
What to check on the label
Source and dietary restrictions. Marine collagen is sourced from fish; bovine collagen is sourced from cattle. Check allergens and dietary suitability on the exact product rather than assuming all powders within a category are alike.
Serving size. Compare the stated amount of collagen with the whole scoop and the number of servings in a container. A blend with sweeteners or creamers may have less collagen than the total scoop weight implies.
Other ingredients. Flavours, sweeteners, vitamins and minerals may be added. Decide whether you want them and check their stated amounts. A vitamin added to a powder is not evidence of a clinical effect from the whole product.
What this guide does not establish
We have not performed a controlled taste, mixability or outcome test of the products in the current catalogue. A type of collagen is not a scored product, so this guide does not give one a site score. For a specific product, check its label and read any product-specific review for a clearly dated synthesis of sampled customer experiences.
If you have an allergy, take medication, or are considering collagen for a health condition, speak to a qualified clinician. Customer comments are not medical evidence.