Adiponectin is probably not a word you’ve heard of, unless your physician mentioned it during a checkup visit. Even if your doctor has discussed your blood glucose levels and body mass index (BMI) with you, it is unlikely that adiponectin was mentioned. So what is adiponectin? The word might sound scary, but adiponectin is a normal hormone in your body and an important marker of your metabolic health. If adiponectin levels are abnormal, disease could occur; but, fortunately, diet and exercise can help you get things back in check. In this article, we’ll demystify adiponectin and explain why it’s important. We’ll also discuss a promising diet that scientists are exploring that can help promote weight loss and a healthy gastrointestinal (GI) microbiome — while simultaneously keeping your adiponectin levels in a healthy range.

What is adiponectin?

Adiponectin is a hormone produced by the human body that is involved in the normal breakdown of sugars and fats. Normal levels of this hormone promote insulin sensitivity, which helps regulate blood sugar (glucose) levels. Adiponectin has also been shown to be important in skeletal tissue development and has anti-inflammatory and anti-atherogenic (i.e., disrupts the formation of fatty plaques in the arteries) effects. But these beneficial properties depend on the maintenance of a delicate balance. Disrupted adiponectin levels — either too high or too low — have been associated with a number of diseases. Too low, and you’re at increased risk for obesity, diabetes and metabolic syndrome. Too high, and you might be at risk for heart failure, an autoimmune disease or metabolic syndrome. However, abnormally high adiponectin levels have also been associated with “metabolically healthy obesity” (MHO) — a condition in which your body is protected from the adverse health effects associated with obesity, despite the fact that you’re clinically obese.

Normal adiponectin ranges for people assigned male at birth:

• People with a BMI less than 25: 5 to 37 micrograms per milliliter (ug/mL)
• People with a BMI of 25 to 30: 5 to 28 ug/mL
• People with a BMI over 30: 2 to 20 ug/mL

Normal adiponectin ranges for people assigned female at birth:

• People with a BMI less than 25: 5 to 37 ug/mL
• People with a BMI of 25-30: 4 to 20 micrograms per milliliter (ug/mL)
• People with a BMI over 30: 4 to 22 ug/mL

Adiponectin in health and disease

The relationship between adiponectin and the development of disease is complex. While there haven’t been any specific genetic factors linked directly to adiponectin levels, obesity is the major driver behind adiponectin levels. Obesity is a complex condition caused by a combination of genetic and environmental factors.

Obesity is the number one risk factor for adiponectin levels that are too low. As fat within adipose tissue increases during obesity, hypoxia results, which downregulates adiponectin. Once adiponectin levels fall below a critical threshold, the hormone no longer exerts its beneficial effects. 

Interestingly, high levels of adiponectin are also involved in the development of metabolic syndrome disorders. In this case, as fat within adipose tissue increases, T-cadherin (an enzyme that modifies cell tissue receptors) decreases adiponectin absorption by tissue, leading to a higher release of adiponectin into the bloodstream. While this looks like too much adiponectin at face value (levels in the blood will be high), levels in the tissue are actually too low to exert their beneficial effects. This is why many of the same diseases can be caused by either high or low adiponectin levels. 

Doctors can test for adiponectin levels through a simple blood draw, which they might recommend if you are obese and at risk for developing diabetes, metabolic syndrome or other obesity-associated conditions. Testing for blood adiponectin has even improved the early detection of gestational diabetes. 

How to increase adiponectin levels

Because obesity is the key risk factor impacting adiponectin levels, one of the most effective ways to restore normal adiponectin levels is through diet. Following a strict diet to reduce fat in adipose tissue and to promote a diverse gut microbiome, which has also been associated with adiponectin, is an important first step to getting healthy. 

The Mediterranean diet has long been recognized as an effective approach for treating obesity and metabolic syndrome, and has also been shown to promote a healthy gut microbiome. Additionally, this diet is associated with improved adiponectin levels, accompanied by improved cognitive function and reduced frailty. Accordingly, your doctor might recommend a Mediterranean diet as part of your treatment plan to lose weight and get your adiponectin levels back to normal. Typically, a Mediterranean diet includes a plentiful amount of fiber-rich whole fruits and vegetables, nuts and seeds and healthy fats; together with modest amounts of lean proteins (fish, meats, eggs) and dairy foods.

The Green-Mediterranean diet is a variation of the Mediterranean diet that includes green tea, green superfoods, a higher intake of plant-based food, healthy fats, and very little poultry and meat. One study examining the effect of the Green-Mediterranean diet found a decrease in Bifidobacterium, a probiotic bacterial species that was also correlated with weight loss. Examination of the bacterial community profile of patients trying the Green-Mediterranean diet additionally found an enrichment for bacterial species that harbor genes associated with fat breakdown. 

Some of the positive effects associated with the Green Mediterranean diet can be attributed to high levels of the polyphenols found in the “superfoods” that comprise the diet. An example is Mankai (also called duckweed), which is a good source of protein, iron and polyphenols. The inclusion of this polyphenol-rich food can help establish and maintain a healthy GI microbiome, promote GI health and help reduce symptoms associated with metabolic disorders. 

Key takeaways

While the word adiponectin might remind you of some random horror film sitting on a shelf at a 1990’s Blockbuster store, it’s not as horrific as it sounds. Adiponectin is a hormone that provides many benefits, including a protective effect against metabolic syndrome and related diseases. When adiponectin levels are too high or too low — usually caused by obesity — disease (including diabetes, heart disease and metabolic syndrome) can ensue. Fortunately, the Mediterranean diet and its close relative, the Green Mediterranean diet, have proven effective for weight loss and alleviating symptoms of metabolic syndrome. So, the next time your doctor mentions the word adiponectin, your rebuttal might simply be, “Mankai!”