. Proline and glycine are the abundant amino acids in broth, and they are generally overlooked and underloved. They are considered non-essential because our bodies make them, but the truth is that when tested our bodies are dramatically deficient, sometimes to the tune of 8-10g of glycine in a day or 20-30% of proline (1,2)! It is clear we can produce it, but just not enough. This can be due to our modern lifestyles of work, artificial light, frankenfoods, alcohol, lack of sleep, small frequent, daily stressors etc... Or because we place dietary restrictions, whether it is on purpose or we just don't have access to a wide variety of foods. We often cut items out of our diet in the hopes of being healthy, but we also leave out plenty of nutrients.
We have written about Glycine and all of the amazing things that this amino acid does in the body, but it is time to discuss Proline now. Proline is key during the healing stages of cells and is vital during the muscle recovery process. Research has shown that the site of an injured tissue can contain up to 50% more proline than a normal site, indicating the importance of proline in tissue repair. Studies on rats found that the administering of proline to injured rats produced a significantly faster healing time and stronger tissue than the control rats (3). Not only is proline used in repair processes, but it also serves as a precursor to hydroxyproline, which is needed to make collagen. Again studies have shown that the proline ingested in gelatin, can actually be directly infused into the collagen of the animal (determined by radio-labels), so not only does it serve as a precursor, but it also becomes directly infused into the collagen. This of course provides important joint protection as time goes on.
Endurance athletes and people who engage in regular vigorous exercise will often be tested with depleted levels of proline. So supplementation with L-proline, geltain or of course regular broth consumption is vital to maintain muscle mass and healthy connective tissue! If you spend many hours a week exercising, make sure you are eating enough and balancing your meat consumption with either broth, organs or skin. If you have nagging skin injuries taking a long time to heal, consider upping your glycine and proline levels. Also in order for proline supplementation to help you, you need adequate vitamin c levels. So if you up your proline intake, make sure you are getting plenty of Vitamin C, as it is essential to the enzymes that utilize proline.
One of the founders of quantum chemistry and molecular biology, Linus Pauling, created a Unified Theory and Therapy for Heart Disease, in which proline is vital to the recovery and resistance to heart disease. But we will discuss this in the next post on Proline! See you next time.