Wikipedia is a poor source of information on advanced glycation end products (AGEs)

A link to Wikipedia is usually on the first page of search results. The Wikipedia post on AGEs lacks the evidence that a reader may infer from its text.

For example, the second paragraph of the AGEs link, Dietary Sources, contained the following text and references:

  1. “However, only low molecular weight AGEs are absorbed through diet, and vegetarians have been found to have higher concentrations of overall AGEs compared to non-vegetarians. [4]
  2. Therefore it is unclear whether dietary AGEs contribute to disease and aging, or whether only endogenous AGEs (those produced in the body) matter. [5]
  3. This does not free diet from potentially negatively influencing AGE, but implicates dietary AGE may be less important than other aspects of diet that lead to elevated blood sugar levels and formation of AGEs. [4] [5]”

[4] https://www.sciencedirect.com/science/article/pii/S0278691513004444 “Advanced glycation end products in food and their effects on health” (not freely available) 2013 Denmark.

Please note on this linked page that a German researcher took the time to correct one bias of the reviewers, citing evidence from his own studies that “The deleterious effects of food-derived AGEs in subjects with type 2 diabetes mellitus are proven.”

[5] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3257625 “Dietary Advanced Glycation End Products and Aging” 2010 US.


Both of these references were reviews. Unlike study researchers, reviewers aren’t bound to demonstrate evidence from tested hypotheses.

Reviewers are free to:

  • Express whatever unsupported beliefs they happen to have;
  • Overemphasize study limitations as if these were the reviewers’ ideas; and
  • Ignore and misrepresent evidence as they see fit.

Reviewers also aren’t obligated to make post-publication corrections for their errors and distortions. For example, the Danes didn’t correct their review with any findings the German researcher presented.

As such, reviews can’t be cited for reliable evidence.

Good job, Wikipedia contributors! You polished up lower-quality material to promote misunderstandings that detracted from science.


A sample of problems with each of the Wikipedia sentences:

1. “However, only low molecular weight AGEs are absorbed through diet, and vegetarians have been found to have higher concentrations of overall AGEs compared to non-vegetarians. [4]”

The first part of sentence 1 came from the review’s abstract:

“Only LMW AGEs..may be absorbed from the gut and contribute to the body burden of AGEs.”

But the reviewers didn’t support their abstract’s statement with direct evidence from any study!

2. “Therefore it is unclear whether dietary AGEs contribute to disease and aging, or whether only endogenous AGEs (those produced in the body) matter. [5]”

The “therefore” of sentence 2 was misplaced. Sentence 1 didn’t attempt to explain whether “dietary AGEs contribute to disease and aging” or “only endogenous AGEs matter.”

Since sentence 2 wasn’t a consequence of sentence 1, the Wikipedia contributor(s) needed to support sentence 2 with evidence. Invoking the “unclear” 2010 reference [5] ignored dozens of later studies that provided better clarity.

3. “This does not free diet from potentially negatively influencing AGE, but implicates dietary AGE may be less important than other aspects of diet that lead to elevated blood sugar levels and formation of AGEs. [4] [5]”

The value judgment of sentence 3 wasn’t unequivocally supported by studies cited in either reference. “Dietary AGE may be less important..” was a biased opinion that didn’t represent an authoritative body of evidence. Contrast it with β€œThe deleterious effects of food-derived AGEs in subjects with type 2 diabetes mellitus are proven.”


Dr. Alan Green pointed out that the Wikipedia glycation post has reliable information in the Exogenous section.

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Disease and advanced glycation end products (AGEs)

This 2015 French/US review focused on chronic kidney disease, appropriate for its publication in the Journal of the American Society of Nephrology:

“Advanced glycation end products (AGEs) are formed not only in the presence of hyperglycemia, but also in diseases associated with high levels of oxidative stress, such as CKD. Humans are exposed to exogenous sources of AGE (diet and cigarette smoke) and endogenous sources of AGE when the organism is exposed to high levels of glucose, such as in diabetes.

Accumulation of AGEs in patients with CKD has been shown to result from inflammation, oxidative stress, and diet. AGEs are proinflammatory and pro-oxidative compounds that play a role in the high prevalence of endothelial dysfunction and subsequent cardiovascular disease in patients with CKD.

In view of the many harmful effects of AGEs on cell function, it is essential to develop strategies designed to counteract their effects. AGEs are generated during the thermal processing and storage of foods. Dietary restriction is an effective, feasible, and economic method to reduce the levels of toxic AGEs and possibly, the associated cardiovascular mortality.”


I came across the AGE subject in the usual Internet way. πŸ™‚ While reading the comments on Josh Mitteldorf’s blog post Money in Aging Research, Part I, Dr. Alan Green mentioned Dr. Helen Vlassara’s work on the subject. A DuckDuckGo search led to her 31,708 citations the first day I checked. That number increases every day.

Another read on the subject is her 2016 book Dr. Vlassara’s AGE-Less Diet: How a Chemical in the Foods We Eat Promotes Disease, Obesity, and Aging and the Steps We Can Take to Stop It. A practical guide is her 2017 book The AGE Food Guide: A Quick Reference to Foods and the AGEs They Contain.

https://www.researchgate.net/publication/281281887_Uremic_Toxicity_of_Advanced_Glycation_End_Products_in_CKD “Uremic Toxicity of Advanced Glycation End Products in CKD” (registration required)