Food Sources of Collagen

Collagen makes up about 25 percent of all the protein in your body, according to the Research Collaboratory for Structural Bioinformatics Protein Data Bank. Special cells manufacture collagen from basic amino acids, so you won't lack collagen if you don't eat collagen-rich food. If you eat complete proteins and consume enough vitamin C, your body makes collagen as needed. Without vitamin C, collagen production stops. Symptoms of scurvy begin when body tissues fail to repair themselves.

Collagen-Building Blocks

Most collagen in food comes from animal sources, although your body can utilize the collagen found in mushrooms. To build tendons, ligaments or other collagen-based tissues, your body must first break down digested protein into its amino acid components. Special cells, such as fibroblasts and osteoblasts, reassemble the amino acids into the type of collagen needed. Animal collagen provides a good source of amino acid-building blocks, but so do other protein sources. If you eat several different types of vegetables, grains and legumes daily, a plant-based diet yields all the amino acids you need to build new collagen.

Meat

Meat, fish and poultry products supply collagen, but the most collagen-rich parts usually don't make it to your plate. Tendons, cartilage and skin consist mainly of collagen and cooks often trim out these tough or fatty tissues. Bones also contain much collagen, but they seldom become part of the meal. You could make collagen soups with the scraps and bones instead of throwing them out. The liquid that accumulates in a roasting pan beneath meat or poultry also makes a thick collagen broth. As the liquid cools, the collagen portion forms a layer of gelatin in the bottom of the pan. Fat solidifies on top.

Gelatin

Boiling collagen unwinds the helical structure of the protein and creates a mass of protein threads. As the collagen soup cools, the proteins absorb the water and form gelatin. When dried, gelatin becomes a yellowish powder easily reconstituted with hot water. By itself, gelatin has little color, flavor or odor. Adding sugar, food coloring and flavoring turns a soup made from cow and pig hides, bones and fish skins -- all primary commercial sources of gelatin -- into a tasty dessert pudding. Gelatin derived from animal byproducts forms the base for many popular desserts and candies.

Supplements

If you don't find collagen foods appealing, you could choose collagen supplements instead. Shark cartilage provides calcium and sulfur as well as collagen, and chondroitin supplements compress the collagen found in the windpipes of cattle into a convenient pill. Concentrated gelatin supplements might yield the same health benefits as more exotic products. A gelatin supplement developed at at the Human Performance Laboratory of Ball State University reduced the knee pain of athletes during a test study conducted in 1997. Gelatin could help heal minor cartilage damage and prevent more serious injuries, according to associate professor David Pearson of Ball State.