AGE Formation (Advanced Glycation End-products)

Advanced glycation end-products form when a sugar attaches to a protein without an enzyme, then rearranges through the Maillard reaction into stable, often cross-linked adducts. Because the reaction has no enzyme to regulate it, the products accumulate on proteins that turn over slowly, which means collagen, lens crystallin and arterial elastin take the worst of it.

John Baynes framed the causation question directly in Experimental Gerontology: over a dozen AGEs have been identified in tissue proteins, and about half are known to accumulate with age in collagen [1]. His argument is that AGE accumulation is a marker of cumulative oxidative and carbonyl stress rather than a proven independent cause of aging, an important distinction that AGE-focused marketing usually skips.

The strongest human outcome data are mixed. Bente Kilhovd, Markku Laakso and colleagues followed 1,141 nondiabetic Finns aged 45 to 64 (535 men, 606 women) from 1982-1984 for 18 years. Serum AGEs predicted all-cause mortality (P = 0.012), cardiovascular mortality (P = 0.018) and coronary heart disease mortality (P = 0.008) in women, and predicted none of the three in men [2]. That sex split has never been fully explained.

A 2022 Journal of the American Heart Association analysis measured five AGEs by mass spectrometry in two cohorts. In the Cardiovascular Health Study, 466 participants aged 65 and older produced 200 incident cardiovascular events over a median 11 years: carboxymethyl-lysine carried a hazard ratio of 1.20 per SD (95% CI 1.01-1.42, P = 0.032) and 3-deoxyglucosone hydroimidazolone 1.45 (95% CI 1.23-1.72, P < 0.001) [3]. In the Multi-Ethnic Study of Atherosclerosis, 1,631 participants and 439 events, nothing held: carboxymethyl-lysine 0.91 (95% CI 0.77-1.06, P = 0.245) [3]. Zeinab Hegab and Mamas Mamas add the clinical context, noting diabetic patients carry a 2 to 4 fold higher cardiovascular risk and that up to 65% of diabetic deaths are cardiovascular [4].

How to move it: lower the glucose exposure. In the PREMOTE trial, Yifei Zhang randomised 409 people with type 2 diabetes; berberine alone lowered HbA1c by 0.99 percentage points (95% CI -1.16 to -0.83) over 12 weeks against 0.59 in the placebo arm, P < 0.001 [5]. HbA1c is itself a glycated protein, so the same lever that lowers it lowers the input to AGE formation. No supplement has been shown to break existing cross-links in humans.

The plain takeaway: AGE chemistry is certain, its causal role in aging is contested, and the practical lever is glucose control rather than any AGE-breaker product.