What Foods Are Highest in Proline?

December 4, 2025 •

3 min read

L-proline is a key amino acid that is particularly abundant in collagen, which makes up about 30% of the body's total protein. To support your body's natural collagen synthesis, it is important to know what foods are highest in proline and incorporate them into your diet.

Quick Summary

Proline is a non-essential amino acid found in many protein-rich foods, with the highest concentrations in those derived from animal connective tissue like gelatin and bone broth. Excellent sources also include dairy, eggs, legumes, and nuts, making it widely accessible through a varied diet.

Key Points

Gelatin and Bone Broth are Top Sources: These animal-based foods, rich in broken-down collagen, contain the highest concentrations of proline per gram.
Connective Tissue Matters: Eating parts of animals with skin, bones, and cartilage, such as chicken wings or tough meat cuts, significantly increases proline intake.
Dairy and Eggs are Good Contributors: Hard cheeses, dried milk powder, and egg whites are notable animal-based sources that provide proline.
Plant-Based Options Exist: Vegans and vegetarians can get proline building blocks from foods like soy protein, legumes, nuts, and spirulina.
Vitamin C is a Critical Partner: Vitamin C is necessary for the conversion of proline to hydroxyproline, which is vital for the stability of collagen.
Dietary Diversity is Key: Consuming a varied diet with multiple protein sources is the most effective way to ensure a sufficient supply of proline.

Proline is a non-essential amino acid, meaning the human body can produce it, but dietary intake is still crucial, particularly during times of increased physical stress, illness, or aging. As a major building block for collagen, proline plays an indispensable role in maintaining the health and integrity of skin, cartilage, tendons, and bones. Understanding the top food sources can help you optimize your nutritional intake to support these vital bodily functions.

Animal-Based Sources of Proline

The most concentrated sources of proline are typically animal products, especially those that contain significant amounts of connective tissue and cartilage. The process of cooking these foods often breaks down the collagen into gelatin, a highly digestible source of proline and other amino acids like glycine.

Gelatin and Bone Broth

Gelatin and its derivative, bone broth, are among the highest and most bioavailable sources of proline. Gelatin powder can contain over 12 grams of proline per 100 grams, while bone broth releases collagen broken down into gelatin and amino acids during simmering. Pork skins, also rich in collagen, provide over 7 grams of proline per 100 grams.

Meats and Poultry

Certain cuts of meat and poultry are excellent sources of proline due to their high collagen content. Tough cuts like beef brisket or oxtail, chicken skin and wings, and certain organ meats (lungs, spleen) are particularly good options.

Dairy Products and Eggs

Dairy products contain casein and whey proteins, which are good sources of various amino acids, including proline. Hard cheeses like Parmesan and Gruyère, and nonfat dried milk are notable sources. Egg whites also contribute proline.

Fish and Seafood

Fish and shellfish offer another source of proline, particularly fish skin and options like whelk.

Plant-Based Sources of Proline

While animal products are more concentrated, many plant-based foods provide the amino acid building blocks your body can use to synthesize proline.

Legumes and Soy Products

Soybeans and soy protein isolate are significant sources of proline. Beans and lentils also provide the necessary amino acids for collagen production.

Nuts and Seeds

Peanuts, cashews, sunflower seeds, and pumpkin seeds contribute proline along with other nutrients.

Vegetables and Grains

Spirulina is a potent plant-based source with a high concentration of proline. Wheat gluten and spelt also contain proline, while vegetables like asparagus and cabbage provide amino acids for synthesis.

Comparison Table: Proline Content in Key Foods (per 100g)

For a detailed list of foods and their proline content, you can refer to {Link: Medindia https://www.medindia.net/nutrition-data/nutrients/proline-rich-foods.htm}. This resource provides a table comparing the proline content in various sources like gelatin powder (~12.3 g), pork skins (~7.3 g), soy protein isolate (~5.0 g), Parmesan cheese (~4.9 g), and dried spirulina (~2.4 g) per 100g.

Conclusion

Foods highest in proline are predominantly animal-based and include gelatin, bone broth, various meats (especially skin-on or tough cuts), dairy, and eggs. Plant-based options like soy products, legumes, nuts, and seeds also provide amino acid building blocks. A varied diet incorporating these sources helps ensure adequate proline intake. For more information on the role of nutrition in supporting connective tissue health, refer to the {Link: Harvard University https://nutritionsource.hsph.harvard.edu/collagen/}.

How to Increase Proline Intake

Increasing proline intake can involve adding gelatin or bone broth to your diet, choosing tougher cuts of meat, and snacking on nuts and seeds. Consuming enough vitamin C is also important for proline conversion.

Frequently Asked Questions

Proline is a non-essential amino acid, meaning the body can produce it, but it can also be obtained through diet. It is a major building block for collagen, the most abundant protein in the body.

Proline is vital for the synthesis and stabilization of collagen, which provides structure and support to connective tissues throughout the body, including skin, tendons, ligaments, and cartilage.

Yes, while animal products are more concentrated, a diverse plant-based diet can provide the amino acid building blocks for the body to synthesize proline. Good sources include soy, legumes, nuts, seeds, and spirulina.

Yes, dry gelatin powder is among the most concentrated sources of proline, containing over 12 grams per 100 grams. It is a derivative of collagen, the primary protein built with proline.

Vitamin C is an essential cofactor for the enzymes that convert proline into hydroxyproline, another amino acid critical for stabilizing the collagen structure. Without enough vitamin C, collagen cannot form correctly.

You can add gelatin powder to beverages, use bone broth as a soup base, cook with tougher cuts of meat, snack on nuts and seeds, or add Parmesan cheese to dishes. Pairing these with vitamin C-rich foods further enhances the benefit.

For most healthy individuals, there are no known risks associated with consuming high-proline foods as part of a balanced diet. However, some studies suggest a potential link between high proline intake and depression risk, though more research is needed to understand the connection.

As the body can synthesize proline, deficiency is uncommon, even in vegetarians and vegans. Consuming a balanced diet with varied protein sources, including legumes, soy, nuts, and seeds, provides ample building blocks.