NB

Collagen, like all proteins, is made up of amino acids. Of these amino acids, nine are considered essential, i.e. they cannot be synthesized by the body and must be acquired through the diet.
Protein: There are nine essential amino acids necessary in collagen production that must be obtained through diet and the consumption of animal product, such as meat, poultry, fish, eggs, and dairy (if tolerated).
Vitamin C: Vitamin C is it is commonly known, plays an important part in stimulating collagen production as well as protecting the skin from the damaging effects of ultraviolet rays. Foods that contain vitamin C include oranges, strawberries, bell peppers, and broccoli.
Gelatin and bone broth: Collagen is naturally found in the skin, bones, and joints of animals and is easily digestible when in the form of gelatin and bone broth. Collagen, when it is cooked, breaks down and becomes gelatin. Mineral and collagen-rich bones, when cooked down, become a gelatin-rich bone broth.
Proline: Found in egg whites, meat, cheese, soy and cabbage
Anthocyanidins: Found in blackberries, blueberries, cherries and raspberries
Copper: Can be found in shellfish, nuts, red meat and some drinking water
Vitamin A: Found in animal-derived foods and in plant foods as beta-carotene.