Adiponectin, a hormone produced by fat cells, helps manage weight, blood sugar and cholesterol levels by acting as a feedback system to reduce appetite and prevent accumulation of excess blood sugar and fats. Adiponectin is normally present in substantial amounts compared to other hormones, and is produced in greater quantities by women than men. Research has illuminated some of the finer points of the intricate interaction among adiponectin, blood sugar control and diabetes.
Childhood Obesity
Low levels of adiponectin are associated with childhood obesity and insulin resistance in girls, according to a study published in the February 2011 issue of the journal "PLoS One." Of over 305 children who participated in the study, overweight and obese girls showed lower adiponectin levels while boys did not show significant variability of adiponectin levels across different weight groups. When adiponectin was compared to leptin -- a hormone for which high levels are associated with increased insulin resistance -- the leptin to adiponectin ratio increased as weight increased in both boys and girls. The researchers concluded that higher levels of leptin in both sexes was a more reliable marker for insulin resistance, overall, than adiponectin.
Vitamin E
A study published in the March 2011 issue of the journal "Nutrition Reviews" found that vitamin E enhances adiponectin activity, resulting in decreased insulin resistance. The researchers note that vitamin E has a similar molecular structure and may have a similar mechanism of action to certain diabetes drugs that promote adiponectin production.
Type 2 Diabetes
Low adiponectin levels may be a predictor for Type 2 diabetes, according to a study published in the February 2011 issue of the journal "Diabetologia." The study found that, in two separate studies with participants' average age in the early 60s, low adiponectin and elevated insulin resistence were associated with Type 2 diabetes, while insulin sensitive people in the studies did not show the same pattern. The researchers concluded that lower adiponectin levels are associated with increased risk for Type 2 diabetes in insulin-resistant individuals.
Metabolic Syndrome
Higher adiponectin levels are associated with increased likelihood for developing metabolic syndrome -- a group of risk factors for cardiovascular disease and diabetes that includes insulin resistance, according to a study published in the 2011 issue of the "International Heart Journal." Researchers found that adiponectin was higher in women than men and also higher in non-smokers and people with higher levels of high density lipoprotein -- HDL -- cholesterol. Patients with coronary heart disease had lower levels of adiponectin. The researchers concluded that adiponectin levels tend to be low in people with metabolic syndrome.
References
- "PLoS One"; Inflammatory adipokines, high molecular weight adiponectin, and insulin resistance: a population-based survey in prepubertal schoolchildren; Murdolo G, et al.; 2011
- "Nutrition Reviews"; Vitamin E and adiponectin: proposed mechanism for vitamin E-induced improvement in insulin sensitivity; Gray B, et al.; 2011
- "Diabetologia"; Insulin resistance influences the association of adiponectin levels with diabetes incidence in two population-based cohorts: the Cooperative Health Research in the Region of Augsburg (KORA) S4/F4 study and the Framingham Offspring Study; Hivert MF, et al.; 2011
- "International Heart Journal"; Association of circulating levels of leptin and adiponectin with metabolic syndrome and coronary heart disease in patients with various coronary risk factors; Kajikawa Y, et al.; 2011
