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 post, 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 studies:

“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 reviews 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 an “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]”

Wikipedia contributors tend to enumerate irrelevant citations rather than get flagged with “needs citation.” The value judgment of sentence 3 wasn’t unequivocally supported by studies referenced in either review.

“Dietary AGE may be less important..” was a biased opinion that didn’t represent an authoritative body of evidence. Contrast it with “The deleterious effects of food-derived AGEs in subjects with type 2 diabetes mellitus are proven.”


Wikipedia’s premise is that since the group knows more about any subject than does any individual, everyone is entitled to “contribute.” This often produces a narrative whose parts lack coherence and relevant evidence.

Dr. Alan Green pointed out that the Wikipedia glycation post has accurate information in the Exogenous section. But with so many editors, Wikipedia is essentially unedited.

For example, in the second paragraph of the Exogenous section:

  • Assertions of the first and third sentences needed citations. Did the contributor(s) think these would be unexaminedly accepted?
  • Someone inserted a cancer reference as the fourth sentence, although it had little to do with the preceding sentences.
  • The most informative sentence was the fifth. An editor would have taken out the repetition of “recent” though, because the citation was from 2005.
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