Oct 10 / Star Khechara

Hydroxylation: The Vitamin C-Driven Process That Strengthens Collagen

Hydroxylation is a vital biochemical process in which a hydroxyl group (–OH) is added to a molecule. In collagen biosynthesis, hydroxylation modifies the amino acids proline and lysine, converting them into hydroxyproline and hydroxylysine. These new forms allow the collagen triple helix to form stable hydrogen bonds, giving collagen its remarkable tensile strength. The reaction requires vitamin C (ascorbic acid) as a cofactor for the enzyme prolyl hydroxylase, meaning vitamin C deficiency leads to defective collagen formation, the cause of scurvy.

References

  1. Pumori Saokar Telang ‘Vitamin C in dermatology’ Indian Dermatol Online J. 2013 Apr-Jun; 4(2): 143–146.
  2. Boyera N, Galey I, Bernard BA. Effect of vitamin C and its derivatives on collagen synthesis and cross-linking by normal human fibroblasts. Int J Cosmet Sci. 1998 Jun;20(3):151-8.
  3. Frey J, Raby N. Lysine et collagène [Lysine and collagen]. Ann Biol Clin (Paris). 1991;49(1):36-9
  4. Protein and Amino Acids (chapter 6) Recommended Dietary Allowances: 10th Edition... (1989).


Hydroxylation is frequently oversimplified.

Without a systems-based framework, it is easy to focus on vitamin C as a simple antioxidant while missing the wider physiological context of enzymatic cofactors and amino acid modification that actually drives skin outcomes.

Understanding how these biochemical systems interact is what turns nutritional information into confident clinical decision-making.
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Star Khechara

Professional agehacker, author, speaker and founder of Skin Nutrition Institute
About me
Skincare formulator and beauty author turned skin-nutrition educator: Star distilled her 20+ years of skin-health knowledge into the world’s first international accredited skin-nutrition school to teach skin therapists, facialists, face yoga practitioners and estheticians how to help their clients feed the skin from within for cellular-level rejuvenation and vibrant beauty. 
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