What it is
Adiponectin is a hormone made by fat cells. UniProt's record (Q15848) gives a 244-residue precursor; removing an 18-residue signal sequence leaves a 226-amino-acid protein. It has a collagen-like stretch, with sugars attached to several hydroxylysine residues, and a globular head, and it circulates as trimers and larger assemblies held together in part by a disulfide bond.
At 226 residues it is a protein, more than five times the 40-residue line US regulation uses to separate peptides from proteins (21 CFR 600.3; see peptide versus protein). The library carries it because readers arrive with the name from metabolic-health articles and lab panels, and because it sits beside leptin, the other well-known fat-cell hormone.
It has had several names. In 1995 a Whitehead Institute group (Scherer et al., J Biol Chem, PMID 7592907) described Acrp30, "a novel 30-kDa secretory protein … made exclusively in adipocytes", structurally similar to the immune protein complement C1q, and "an abundant serum protein". A Japanese group isolated the same gene product as apM1 and, in 1999, named it adiponectin (Arita et al., PMID 10092513).
What it does
UniProt describes adiponectin as an adipokine involved in the control of fat metabolism and insulin sensitivity, acting through two receptors, AdipoR1 and AdipoR2, with anti-inflammatory and anti-atherogenic activities. Two points about that annotation matter:
- Several of the actions are marked "by similarity" — inferred from the corresponding animal protein, such as its activation of the energy-sensing enzyme AMPK in liver and muscle — rather than shown directly for the human protein.
- None of it comes from treating people with adiponectin. No adiponectin product has been tested as a medicine. What exists in humans is measurement: levels compared between groups, and levels tracked as an outcome when something else is given.
The most-cited human finding is the one in the 1999 paper's title: a "paradoxical decrease" in obesity. The authors built an assay, measured healthy volunteers (reporting a range of 1.9 to 17.0, with the unit printed in the abstract as mg/ml) and found plasma concentrations in obese subjects significantly lower than in non-obese subjects — although fat tissue is the only source.
| What is described | How firm |
|---|---|
| Made by fat cells, abundant in blood | Human measurement (1995, 1999) |
| Lower in obesity | Human measurement (Arita 1999) |
| Acts through AdipoR1 and AdipoR2 | UniProt annotation |
| Insulin-sensitising, AMPK-activating | Partly inferred from animal work ("by similarity") |
| Raising it treats disease | No human treatment trial of adiponectin exists |
The blood test
Adiponectin is measured mostly in research and in specialist metabolic work rather than as a routine test, and laboratories set their own reference ranges. What a reading means for any one person is for the clinician who ordered it. A lower value is associated with obesity and insulin resistance in the literature; it does not by itself diagnose anything, and this entry does not interpret results.
Diet, drugs and supplements
Most of adiponectin's 1,687 randomised-trial records on PubMed measure it as an outcome — how a diet, an exercise programme, a drug or a supplement moved the level. A marker moving is not a health outcome, and none of those studies makes the intervention an adiponectin treatment. This library found no product approved for raising adiponectin, and articles listing "adiponectin-boosting foods" are not reporting an approved effect.
Where it stands
- No adiponectin medicine exists, and no approved drug acts directly on its receptors.
- Published record: PubMed returns 28,308 records for adiponectin, 1,687 tagged as randomised controlled trials; ClinicalTrials.gov lists 1,618 studies that mention it (all 2026-10-27).
- What is established in humans is that it is a fat-cell protein present in blood and lower in obesity; its effects as a treatment are untested.
Related reading
Leptin is the other well-known hormone fat cells make, the one that tells the brain how much energy is stored. GLP-1 is the gut hormone behind the current weight-loss medicines, and amylin the pancreatic one now being developed alongside it.