What Is Exogenous Glycation?
While endogenous glycation occurs within the body, exogenous glycation refers to the pre-formed Advanced Glycation End Products (AGEs) that enter the body through food. These glycotoxins accumulate from certain ingredients and cooking methods, particularly those involving high fat and high heat.
When consumed, these compounds add to the body’s overall AGE load, amplifying inflammation and oxidative stress, both of which compromise skin health and accelerate the ageing process.
When consumed, these compounds add to the body’s overall AGE load, amplifying inflammation and oxidative stress, both of which compromise skin health and accelerate the ageing process.
...dietary AGEs present in food commonly
consumed in a 'western-style' diet, contribute
significantly to the body's AGE pool. Moreover,
these diet-derived AGEs have a significant
association with indicators of inflammation in
healthy subjects
Where Dietary AGEs Come From
The foods richest in exogenous AGEs are typically animal-based and high in fat and protein. Meats, dairy products, fish and extracted oils all produce substantial amounts of AGEs when cooked. Among the worst offenders are fried bacon, butter, hard cheeses and roasted or grilled meats.
By contrast, whole plant foods such as fruits, vegetables, legumes and grains contain negligible levels of AGEs. These carbohydrate-rich foods are naturally low in fat and protein, meaning they’re less prone to glycation reactions during cooking.
For example:
For practitioners, these figures illustrate just how strongly diet composition affects the body’s exposure to glycotoxins.
By contrast, whole plant foods such as fruits, vegetables, legumes and grains contain negligible levels of AGEs. These carbohydrate-rich foods are naturally low in fat and protein, meaning they’re less prone to glycation reactions during cooking.
For example:
- Fried bacon can contain over 90,000 AGE units per 100g.
- Butter, cheese and cream range from 10,000–25,000 AGE units per 100g.
- Fresh fruits and vegetables contain fewer than 30 AGE units per 100g.
For practitioners, these figures illustrate just how strongly diet composition affects the body’s exposure to glycotoxins.
The Role of Cooking Methods
Eating food raw (such as salads or fresh fruit) or using a cooking technique can make the difference between a low-AGE and high-AGE meal. The Maillard reaction, responsible for the browning and crisping of food, is essentially glycation in action. Whenever proteins or fats are exposed to high temperatures without moisture, AGEs are created.
The worst cooking methods for AGE production include:
The worst cooking methods for AGE production include:
- Frying
- Grilling or broiling
- Roasting
- Barbecuing
These methods combine heat, dryness and fat, the perfect storm for glycation.
By contrast, low-heat, water-based methods produce minimal AGEs.
The best approaches include:
- Steaming
- Boiling or simmering
- Poaching
- Sous-vide or slow-cooking
- Eating food raw (such as salads or fresh fruit)
Encouraging clients to shift from dry-heat to moist-heat cooking can significantly reduce AGE intake without sacrificing flavour or nutrition.
The Daily AGE Threshold
Research indicates that consuming around 5,000 AGE units per day keeps dietary glycation low, while intakes above 12,000–20,000 units are considered high and associated with inflammation. The average Western diet easily exceeds this range due to its heavy reliance on animal products, processed fats and high-temperature cooking.
Reducing dietary AGEs not only supports skin health but also improves systemic wellness, including reduced risk of metabolic and cardiovascular issues, both of which influence the skin’s appearance and repair capacity.
Reducing dietary AGEs not only supports skin health but also improves systemic wellness, including reduced risk of metabolic and cardiovascular issues, both of which influence the skin’s appearance and repair capacity.
Perhaps surprisingly, foods rich in both protein and fat,
and cooked at high heat, tend to be the richest dietary
sources of AGEs, whereas low-fat carbohydrate-rich
foods tend to be relatively low in AGEs. Conceivably,
this reflects the fact that the so-called "AGEs" in the
diet are generated primarily, not by glycation reactions,
but by interactions between oxidized lipids and protein
Glycation Inhibitor Foods
Certain plant compounds actively inhibit AGE formation and help neutralise oxidative damage. Key examples include:
These foods demonstrate that a plant-based diet not only avoids glycotoxins but also actively counteracts them.
- Cinnamon – inhibits formation of oxidative AGEs in the body
- Garlic – Aged garlic extracts may inhibit formation of AGEs
- Rosemary – In studies exhibited an anti-glycation effect on collagen
- Green tea – Inhibits formation and accumulation of glycotoxins
These foods demonstrate that a plant-based diet not only avoids glycotoxins but also actively counteracts them.
Anti-Glycation Phytochemicals
- Rutin & Quercitrin (not Quercetin) – From buckwheat
- Anthocyanins – On Blue/purple fruits & vegetables
- Alpha Lipoic Acid – broccoli, tomatoes and spinach
- Curcumin – Turmeric
- Vitamin C - All fruits
- Vitamin B3 - Niacin
Plant foods prevent glycation in three ways
Practical Guidance for Practitioners
When working with clients concerned about skin ageing, you can integrate exogenous glycation awareness into both dietary and lifestyle recommendations:
These small yet strategic adjustments can reduce systemic AGE load and visibly improve skin tone, firmness and radiance over time.
Conclusion
Exogenous glycation shows how the way we cook and eat directly influences skin health. For professionals in skincare and wellness, this knowledge is powerful; it allows you to connect daily dietary habits with visible outcomes.
By guiding clients towards low-fat, wholefood, plant-based meals prepared with gentle cooking methods, you help them reduce internal and external glycation damage. The result is not only younger-looking skin but a healthier body overall, proof that radiant skin truly begins in the kitchen.
By guiding clients towards low-fat, wholefood, plant-based meals prepared with gentle cooking methods, you help them reduce internal and external glycation damage. The result is not only younger-looking skin but a healthier body overall, proof that radiant skin truly begins in the kitchen.
References
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Article by Star Khechara
Professional agehacker, author, speaker, founder of skin nutrition institute
About me
Ex-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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