We made a conscious choice to use only fish collagen, despite bovine collagen being much, much cheaper— and so should you.
Not only is fish collagen free of slaughter-house diseases, more sustainably sourced, and frankly better tasting, it is also more effective. Plus, between sterilized fish skin and cow hides boiled in acid, it's really a no-brainer. Right?
Besides, we would never want to cut corners, especially when it comes to health, and neither should you.