Glycation and cross-linking cause extrinsic aging. This kind of aging is due to environmental factors such as your diet and lifestyle, not genetics.
Unlike factors like DNA repair and mitochondria, glycation and cross-linking are largely within your control. In other words, you can slow down extrinsic skin aging by minimizing their damaging effects.
Let’s take a look first at cross-linking.
Cross-linking occurs when a protein links to another protein, sugar, or lipid.
Some cross-linking in the body is essential to life. But abnormal cross-linking ages skin.
For example, collagen is a protein that happens to be fairly large. When collagen fibers are cross-linked to each other, two things happen:
- They become hard and stiff
- They obstruct nutrient and waste transfer
Damaged collagen shows up on skin as wrinkles, sagging, swelling, and discoloration. Cross-linking also causes arteries to harden and joints to stiffen.
What causes cross-linking?
Sugar (glucose) is a big one. Free radicals too. Things that trigger free radicals also promote cross-linking, such as UV, smoke, x-rays, heavy metals, peroxides, and more.
Glycation is a type of cross-linking. It occurs when glucose (a type of sugar) attaches to a protein.
A common analogy is the browning and hardening of a pie crust. This is called the Maillard reaction. Glycation causes a ‘crème brulee’ effect on collagen, elastin, and other proteins. It denatures these proteins, impairing their function.
These abnormal structures are called Advanced Glycation End Products (AGE’s).
AGE’s bind strongly to collagen and elastin (more so to elastin), forming chemical bridges. When this happens, collagen and elastin become stiff and non-functional. This is an irreversible process too (at present).
Skin becomes thinner and less elastic, less flexible, and less firm (more sagging).
AGE’s also make skin sallow (yellow-brown in color) over time due to collagen and elastin not getting broken down properly. The cell has a tough time eliminating these large clumps of cross-linked collagen and elastin fibers. So they accumulate inside the cell as cellular garbage. The This cellular garbage creates an age-related pigment called lipofuscin, which appears on skin as brown spots (they’re different from sun-induced brown spots).
And if that’s not bad enough, AGE’s also increase free radical production, trigger inflammation, decrease circulation, and impair the skin’s ability to regenerate.
How to Minimize Glycation and Cross-Linking
- Avoid eating foods cooked at high heat or foods cooked for a long time in high heat
- Wear sunscreen to protect skin from the sun and limit sun exposure (glycation is catalyzed by heat)
- Maintain a healthy diet. Watch your sugar intake and make sure it’s not too high
Anti-Glycation Ingredients (AGE Inhibitors):
While there are no conclusive studies on ingredients that inhibit glycation, here are some ingredients that are reported to help:
- Alpha Lipoic Acid
- Arginine-Lysine (ARG-LYS) polypeptide
- Benfotiamine (Vitamin B1)
- Glucosamine HCl
- Gotu Kola (Centella asiatica)
- Green Tea
- Kombuchka (trade ingredient containing black tea ferment)
- Lysine (an amino acid)
- Myricetin (a flavonoid)
- Olive leaf
- Pyridoxamine (form of Vitamin B6)
- Soybean (Glycine soja)
- Sunflower seeds (rich in lysine)
- Vitamin E (tocopherol)
- Vitamin C (ascorbic acid)