Glycosaminoglycans (GAGs) are molecules found in the dermis of the skin and are critical for holding and trapping water. As we get older our dermal GAG content can drop dramatically and this at least partially accounts for many of the signs of skin aging.
The most famous GAG molecule in the skin is also the simplest. It’s called Hyaluronic Acid (HA) and over the last 20 years or so it has become a skin care ingredient darling with many topical products taking advantage of its substantial water trapping properties for hydration.
Nonetheless applying Hyaluronic Acid directly to the skin is unlikely to have any significant anti-aging benefits. For that you need to eat HA in foods like bone broth, organ meats and eggs (sorry vegans HA is not found in veggies!). You can also supplement with HA, 100-200 mg daily can provide important moisturization, anti-wrinkle and overall skin health and healing benefits.