AGEs: How diet can cause premature skin ageing

Every food has a unique effect on the human body. Some foods are high in vitamins and minerals, other foods are high in protein and even more foods are high in sugar. A foods nutritional profile matters. While most people focus on avoiding commonly thought of unhealthy foods like fast-food, fried foods and sweets, it is extremely uncommonly known that eating foods with a high level of an ingredient called an advanced glycation end product (AGEs) or a high potential to cause glycation inside of the skin can have dramatic and negative effects on skin ageing.

What are advanced glycation end products?

AGEs are an ingredient which can be naturally found in foods, created in foods as a consequence of cooking or created in situ inside of a person’s body. They’re made by a reaction between protein and sugar and therefore they’re found in places where sugar and protein exist in large quantities.

The AGE content of foods has been largely neglected until recent years as physicians believed AGEs were not able to be absorbed directly by the human body. Scientists now understand, up to 10 to 30% of AGEs consumed in the human diet may be absorbed1 and their effects are highly pro-inflammatory.

AGEs may also be formed inside of the human body as a consequence of a person’s dietary choices2. Protein is a major component of the human body, collagen, for example, is a protein. If sugar or blood glucose levels rise quickly, AGEs may be formed directly inside of human tissue – potentially the most noticeable cause of premature skin ageing.

Why are advanced glycation end products bad?

The reaction which causes the formation of AGEs is scientifically referred to as a cross-linking reaction meaning strong bridges are formed from 1 collagen fibre to another. Normally collagen fibres are able to glide past one another smoothly, in these instances, and when collagen is healthy, the skin is elastic and pliable. However, when collagen becomes glycated, collagen fibres are roughly bound together, becoming tough and hardened – the result – fine lines, wrinkles, and elastosis.

Evidence also suggests extrinsic ageing factors such as UV exposure can speed the rate of AGE formation. Studies have shown that young skin (which typically has no significant accumulation of AGEs) has a noticeable deposition of AGEs in sun-exposed areas of skin3,4. Interestingly this infers the negative effects of UV light are not solely a consequence of oxidation and free radical generation but also a consequence of a person’s diet.

How does glycation cause aging?

The AGE content of skin is directly linked with skin ageing. The presence of glycated collagen is in general detected from age 20 with studies predicting a 3.7% increase per year thereafter5, 6. Areas of skin having a high content of AGEs show impaired collagen function (i.e. collagen which is stiff with decreased flexibility), has reduced the antioxidant ability, is affected by inflammation, has decreased cell proliferation and has decreased collagen and protein synthesis7.  Changes which lead to the characteristic visual markers of aged skin i.e. fine lines, wrinkles, laxity, jowls, pigmentation, and roughness.

What foods are high in AGEs?

A 2010 study published in the journal of the American Dietetic association uniquely discloses the AGE content of over 500 foods8. The AGE content of foods is listed and measured in AGE content per 100 grams of food or AGE content per normal serving size.

A few overall conclusions may be drawn from this study;

  • Diets rich in animal foods have a higher content of AGEs
  • Meats cooked at high heat/dry heat or high and dry heat, have a high AGE content
  • Lamb out of all meats has the lowest AGE content
  • Lean meats have a high content of AGEs due to specific kinds of fat and sugar found within muscle tissue
  • Fats contain a high percent of AGEs
  • Carbohydrates, fruits, and vegetables have the lowest content of AGEs

Therefore it can be concluded a predominantly plant-based diet with a large content of raw and natural foods Is highly protective of a person’s skin age. Take a look at the following comparisons;

  • A portion of roasted beef contains >5, 400 AGEs whereas raw salmon (sashimi) contains 475 AGEs
  • A portion of feta cheese contains > 2, 500 AGEs whereas an apple contains 45 AGEs
  • A portion of butter contains over 1, 300 AGES whereas a portion of olive oil contains 595 AGEs

The highest ranking foods with over ten thousand AGEs per serving size are all animal meats cooked at high heat;

  • 16, 668 AGEs – chicken with skin on (back or thigh) roasted then BBQ
  • 11, 905 AGEs – bacon fried for 5 minutes with no added oil i.e. dry heat
  • 10, 143 AGEs – 5 minute broiled beef frankfurter
  • 10, 058 AGEs – pan-fried steak in olive oil

Can eating AGEs cause skin ageing?

The human body absorbs up to 30% of all AGEs ingested, however, AGEs are already glycated, therefore can they still have detrimental effects on skin ageing?

AGEs are known amongst the scientific community as glycotoxins, ingredients which promote oxidation and inflammation and are considered pathogenic when present in high enough quantities. Studies show that diets rich in glycotoxins are associated with conditions such as poor vascular health (atherosclerosis)9 and kidney disease10 and that the opposite – the consumption of a diet low in AGEs can lengthen lifespan in mice, accelerate wound healing and improve vascular, kidney health and insulin sensitivity11. AGEs are reactive molecules which when ingested can activate molecular pathways involved in inflammation, immune response, cell proliferation and gene expression12.

While collagen hardening is mostly associated with in situ glycation – a topic we’ll explain soon, other routes of skin ageing are noted to be activated by direct consumption of AGEs. For example, a diet rich in AGEs can;

  • Decrease healthy skin cell metabolism
  • Cause cell death
  • Increase collagen degradation
  • Cause inflammation (i.e. inflammageing)
  • Cause skin to be ultra-sensitive to the ageing effects of UV light
  • Deplete skin’s antioxidant defence networks

All factors which may noticeably speed the visible effects of skin ageing. Fine lines and wrinkles, for example, may be formed prematurely in areas of skin with low amounts of antioxidants. Skin which experiences low grade but persistent inflammation e.g. inflammageing will also be prone to the development of fine lines and wrinkles.

The bottom line: Consumption of a diet high in AGEs is highly likely to induce premature skin ageing.

How does glycation affect the skin?

AGEs may also be formed directly inside of skin as a consequence of skin tissue being protein based and energy being supplied to cells as blood-sugar. Protein plus sugar in the right conditions causes glycation to occur.

It is known that diabetics have an increased rate of skin ageing – a side effect largely attributed to an increased blood-sugar level which makes the increased formation of AGEs inside of skin possible.

When glycation occurs inside of the skin, proteins become toughened. Collagen is a predominant skin protein which together with elastin forms a healthy, voluminous and wrinkle-resisting skin appearance. However, when toughened by glycation the opposite is true. In healthy skin, old collagen proteins may be removed and replaced by new and healthy collagen proteins. When collagen fibres are glycated they resist degradation, therefore, accelerating signs of premature ageing13.

The bottom line: Diets high in sugar and high glycaemic index foods are highly likely to cause premature skin ageing.

Can the ageing effects of AGEs be counteracted?

There is promising evidence of the ageing effects of consuming a diet rich in AGEs or a high sugar diet which may cause glycation inside of skin can be counteracted or mitigated with daily alpha lipoic acid supplements. To date, all significant testing has been completed in the animal model with obtained results showing an almost complete reversal of glycated collagen levels.

Alpha lipoic acid (ALA) is naturally found inside of every cell in the human body, being widely referenced as an antioxidant. ALA is believed to help reduce the effects of glycation induced ageing by two mechanisms14

  1. ALA can help decrease blood glucose levels i.e. sugar levels
  2. ALA can help prevent oxidation while also recycling important antioxidants such as vitamin C, vitamin E, and glutathione

The first way in which alpha lipoic acid works, if matched in a human model will prove extremely helpful for reducing glycation within the body. If fewer sugar molecules are available for glycation reactions, fewer glycation products will be formed. As a result, the integrity and youthful flexibility of collagen may be maintained.

The second way in which alpha lipoic acid works is by protecting tissues from the highly oxidative effects of ingested AGEs. Vitamin C, for example, is necessary for healthy collagen production and its levels are reduced in diabetic animal models. Consumption of ALA when at 35mg/kg of body weight can reverse diabetic reduction of vitamin C levels, therefore helping protect skin against the ageing effects of dietary found AGEs.

The bottom line: Daily alpha lipoic acid supplementation looks highly promising for helping protect against the ageing effects of diet-induced glycation.

How to reduce advanced glycation end products naturally

Many natural herbs and spices are also showing promise for helping inhibit glycation and the production of AGEs. Some of the most notable include;

  • Ginger
  • Cinnamon
  • Cloves
  • Marjoram
  • Rosemary
  • Tarragon

This selection of herbs and spices may act similarly to alpha lipoic acid. Cinnamon, for instance, has been shown to be helpful for reducing blood glucose levels after meals15 and a reduced blood sugar level means fewer sugar molecules are available for glycation reactions.

Note: Both glucose and fructose are responsible for glycation, however, fructose is more reactive than glucose. Modern diets contain increased levels of fructose due to new foods such as high fructose corn syrup. A further reason why diets high in natural foods are most protective of skin age.

Herbs and spices are potent sources of natural antioxidants, of which one group – named polyphenols are notable for their anti-glycation benefits. Polyphenol content is seen to directly correlate with the inhibition of glycation with 50% of glycation typically being inhibited by a 4-12ug/ml concentration16. The same 2008 published study concluded the following extracts of herbs and spices as most effective;

  • Cloves
  • Jamaican allspice
  • Cinnamon
  • Sage
  • Marjoram
  • Tarragon
  • Rosemary

The same study also concluded the total phenolic concertation of certain powdered spices i.e. ginger were less than expected. This is thought to be due to the manufacturing process causing degradation of precious phenolic antioxidants. Another show that raw and natural ingredients are most potent and beneficial for human health.

The bottom line: Herbs and spices can have a significant and protective effect on a person’s skin ageing by inhibition of glycation reactions for which cinnamon, Jamaican allspice, cloves, sage, marjoram, tarragon, and rosemary look most effective.

Anti-glycation effects of skincare

Products applied to the skin may also have reversing effects on skin glycation. Notably, a recent study tested the topical use of a cream containing AGE inhibiting blueberry extract. Although the study was too short to investigate a reduction of AGEs within the skin, the small sample size did show a significant improvement in fine lines, skin firmness, radiance, skin tone and skin smoothness17.

As the presence of AGEs within skin makes skin more sensitive to the effects of UV light, daily use of skincare containing potent antioxidants such as our griffin+row centess+ complex is highly likely to protect skin against the negative effects of AGEs.

The bottom line: skin may be protected from AGE induced premature ageing by using skincare rich in antioxidants.

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  11. URIBARRI J, WOODRUFF S, GOODMAN S, et al. Advanced Glycation End Products in Foods and a Practical Guide to Their Reduction in the Diet. Journal of the American Dietetic Association. 2010;110(6):911-16.e12. doi:10.1016/j.jada.2010.03.018.

  12. Paraskevi Gkogkolou & Markus Böhm (2012) Advanced glycation end products, Dermato-Endocrinology, 4:3, 259-270, DOI: 10.4161/derm.22028

  13. DeGroot J, Verzijl N, Wenting-Van Wijk MJ, Bank RA, Lafeber FP, Bijlsma JW, et al. Age-related decrease in susceptibility of human articular cartilage to matrix metalloproteinase-mediated degradation: the role of advanced glycation end products. Arthritis Rheum 2001; 44:2562-71; PMID:11710713; https://dx.doi.

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  14. Lipoic acid prevents collagen abnormalities in tail tendon of high-fructose-fed rats. Thirunavukkarasu V, Nandhini AT, Anuradha CV. Diabetes Obes Metab. 2005 May;7(3):294-7.

  15. Inhibition of protein glycation by extracts of culinary herbs and spices. Dearlove RP, Greenspan P, Hartle DK, Swanson RB, Hargrove JL. J Med Food. 2008 Jun;11(2):275-81. doi: 10.1089/jmf.2007.536.

  16. Inhibition of protein glycation by extracts of culinary herbs and spices. Dearlove RP, Greenspan P, Hartle DK, Swanson RB, Hargrove JL. J Med Food. 2008 Jun;11(2):275-81. doi: 10.1089/jmf.2007.536.

  17. An evaluation of the effect of a topical product containing C-xyloside and blueberry extract on the appearance of type II diabetic skin. Draelos ZD, Yatskayer M, Raab S, Oresajo C. J Cosmet Dermatol. 2009 Jun;8(2):147-51. doi: 10.1111/j.1473-2165.2009.00428.x.