Glycans are chains of sugars (carbohydrates) that enzymes attach to proteins and lipids in the process of glycosylation. This "sugar fringe" is not decoration: it works as a switch, changing the protein's function.
The set of all the body's glycans is called the glycome. Unlike the genome it is dynamic and reflects both heredity and lifestyle, which is why the glycome is regarded as a promising biomarker of aging.
What glycans do
Glycosylation is one of the most common protein modifications. Glycans take part in cell-to-cell recognition, immune function, blood clotting and defense against pathogens. N-glycans on antibodies can switch their pro-inflammatory properties on and off.
That is why a change in glycans is not just a chemical detail but a shift in how the immune system and vessels behave.
Glycans and aging (GlycanAge)
With age the profile of immunoglobulin G N-glycans changes in a regular way: galactosylation declines and the proportion of "agalactosylated" forms (G0), which enhance inflammation, grows. These changes are so closely tied to age that the GlycanAge biological-age test is built on them.
In essence the glycome reflects the level of chronic inflammation and "stitches together" immune aging with cardiovascular risk.
Practical meaning
The glycan clock is still a research tool and is not part of routine check-ups. Its value lies in the fact that some glycan changes are reversible: a healthy diet, physical activity, weight loss and lower sex-hormone levels shift the profile in a "younger" direction more strongly than many other biomarkers.
Calculate using this marker
Calculators where Glycans is used directly:
Frequently asked questions
How does GlycanAge differ from epigenetic clocks?
Epigenetic clocks read DNA methylation, whereas GlycanAge reads the profile of sugar chains on antibodies. Glycans reflect the inflammatory, "immune" component of aging more strongly and respond more visibly to lifestyle changes.
Can I improve my glycan profile?
Partly, yes. Unlike genes, the glycome is plastic: weight loss, regular physical activity, quitting smoking and a healthy diet reduce the proportion of pro-inflammatory glycans. There are no quick, proven "pills" for this.