Collagen Glycation: The Hidden Process That Ages Your Skin (And How to Slow It Down)

Collagen Glycation: The Hidden Process That Ages Your Skin (And How to Slow It Down)

You’ve probably heard that sugar isn’t great for your health. But did you know that it can also make your skin age faster?

One of the main ways this happens is through a process called glycation.

What Is Glycation?

Think of collagen as the scaffolding that keeps your skin firm, smooth, and youthful. Along with elastin, it gives your skin its strength and flexibility.

When there is too much sugar circulating in your bloodstream, some of it sticks to collagen fibres in a process called glycation. This happens without the help of enzymes and results in the formation of harmful compounds called Advanced Glycation End Products, or AGEs (Wang et al., 2024).

As these AGEs build up, they act like glue between collagen fibres, causing them to become stiff, brittle, and less flexible. Scientists call this “cross-linking.” Instead of collagen fibres sliding smoothly past one another, they become stuck together, making it much harder for your skin to stretch, bounce back, and repair itself (Zheng et al., 2022; Pageon et al., 2013).

Over time, this contributes to many of the visible signs of aging, including wrinkles, sagging, dullness, dryness, and uneven skin tone (Zgutka et al., 2023).

The good news is that many of the biggest drivers of glycation are within your control.

How Glycation Ages Your Skin

Research shows that glycation affects your skin in several important ways.

1. It Makes Collagen Stiff

Collagen is designed to be both strong and flexible. Glycation changes its structure by creating permanent cross-links between collagen fibres.

As collagen becomes stiffer, your skin loses elasticity, making wrinkles more noticeable and reducing your skin’s ability to spring back after movement (Zheng et al., 2022; Zgutka et al., 2023).

2. It Increases Inflammation

AGEs don’t simply sit in your skin. They activate receptors called RAGE, which trigger inflammation and oxidative stress.

This inflammation damages the skin cells responsible for producing new collagen and increases enzymes that break down existing collagen even faster (Wang et al., 2024; Sultana et al., 2024).

3. It Weakens Your Skin Barrier

Healthy skin holds moisture inside while keeping irritants out.

People with higher levels of AGEs tend to have poorer skin hydration and greater water loss through the skin, meaning their skin barrier doesn’t function as well (Martinović et al., 2023).

4. It Can Make Skin Look Dull

As AGEs accumulate, they develop a yellow-brown colour that can contribute to dull, uneven-looking skin over time (Zheng et al., 2022).

What Causes Glycation?

While glycation is a natural part of aging, certain lifestyle habits speed it up considerably.

Eating Too Much Sugar

High blood sugar gives your body more opportunities to form AGEs. Diets high in sugary drinks, desserts, candy, refined carbohydrates, and ultra-processed foods can all contribute to greater glycation over time (Zheng et al., 2022; Wang et al., 2024). 

I recommend being cautious with ultra-processed, seemingly “healthy”, high-protein, plant-based, gluten-free, and dairy-free foods. Many contain additives such as emulsifiers, flavourings and preservatives, and diets high in ultra-processed foods have been linked with increased inflammation and a higher risk of chronic diseases, including type 2 diabetes and certain cancers. 

Cooking Foods at Very High Temperatures

It’s not just what you eat, but how you cook it.

Foods cooked using high heat and very little moisture produce much larger amounts of AGEs.

Cooking methods that create the most AGEs include:

• Frying
• Grilling
• Barbecuing
• Roasting
• Charring
• Air frying (less than deep frying but still problematic)

The longer foods are exposed to these cooking methods, the more AGEs they produce (Gill et al., 2019; Ufuk et al., 2025).

Lower-temperature cooking methods such as steaming, poaching, simmering, boiling, pressure cooking, and stewing generally produce far fewer AGEs.

Eating Lots of Processed Foods

Many processed foods combine refined sugars, refined carbohydrates, unhealthy fats, and industrial high-heat manufacturing, creating multiple sources of AGEs in one product (Zawada et al., 2022).

Other Lifestyle Habits That Increase Glycation

Diet is only part of the story.

Research also shows that several lifestyle habits accelerate AGE accumulation in the skin.

Smoking

Cigarette smoke contains AGEs and also stimulates your body to produce more of them. Smokers consistently have higher AGE levels than non-smokers (Zgutka et al., 2023).

Too Much Sun Exposure

Ultraviolet (UV) radiation increases glycation and oxidative stress within the skin. This is one reason why sun-exposed areas tend to age much faster than areas protected from the sun (Zgutka et al., 2023).

Physical Inactivity

Regular exercise helps improve blood sugar regulation and metabolic health. A sedentary lifestyle is associated with greater AGE accumulation (Zhang et al., 2025; Zawada et al., 2022).

Poor Blood Sugar Control

People with diabetes or chronically elevated blood sugar develop AGEs much more rapidly, which contributes to accelerated skin aging and slower wound healing (Buszka, 2023; Zawada et al., 2022).

Air Pollution

Emerging research suggests that long-term exposure to air pollution may also increase AGE accumulation and oxidative stress in the skin (Zgutka et al., 2023).

How to Reduce Glycation Naturally

While you can’t stop aging altogether, you can reduce many of the factors that accelerate glycation.

Science supports:

• Eating fewer sugary foods and drinks.
• Limiting ultra-processed foods.
• Choosing steaming, boiling, poaching, or stewing more often than frying or grilling.
• Eating plenty of colourful vegetables, fruits, herbs, legumes, nuts, and seeds, which provide antioxidants that help combat oxidative stress and reduce inflammation.
• Exercising regularly.
• Protecting your skin from excessive UV exposure with clothing, shade, and sunscreen.
• Avoiding smoking.
• Maintaining healthy blood sugar levels through a balanced diet and regular physical activity (Prasad et al., 2019; Wang et al., 2024).

The Bottom Line

Glycation is one of the major processes that causes our skin to age from the inside out. As sugar binds to collagen and elastin, these important proteins become stiff and damaged, contributing to wrinkles, sagging, dryness, dullness, and loss of elasticity.

Fortunately, many of the biggest drivers of glycation are lifestyle-related. By reducing added sugars, limiting heavily processed foods, choosing gentler cooking methods, protecting your skin from the sun, staying physically active, and eating a diet rich in colourful whole plant foods, you can help slow this process and support healthier skin as you age.

Healthy skin isn’t just about the products you apply to your face. It’s also about the everyday choices that protect your collagen from the inside out.

Want to Go Deeper?

If you’re ready to explore both the inside-out and outside-in approach to skin health, I’m creating a full video series for you:

👉 Skin Health: Inside-Out & Outside-In Playlist
https://www.youtube.com/playlist?list=PL-Jz-7U8Hy6rhQ_mTTk1Hur_pfEmw4jYn

This series walks you through practical, evidence-informed strategies to support your skin at the root level.