Avocatin B, a fat molecule found only in avocados (Persea americana), can inhibit cellular processes that normally lead to diabetes, according to a study published in the journal Molecular Nutrition and Food Research.
“Eating avocados alone would likely be ineffective, as the amount of natural avocatin B varies widely in the fruit and we still do not fully understand exactly how it is digested and absorbed when we consume a whole avocado,” said Professor Paul Spagnuolo, a researcher in the Department of Food Science at the University of Guelph.
Obesity is a leading cause of type 2 diabetes. Insulin resistance in diabetic patients means their bodies are unable to properly remove glucose from the blood. Those complications can arise when mitochondria are unable to burn fatty acids completely.
Normally, fatty acid oxidation allows the body to burn fats. Obesity or diabetes hinders that process, leading to incomplete oxidation.
Professor Spagnuolo and colleagues discovered that avocatin B counters incomplete oxidation in skeletal muscle and the pancreas to reduce insulin resistance.
In the study, they fed mice high-fat diets for eight weeks to induce obesity and insulin resistance. For the next five weeks, they added avocatin B to the high-fat diets of half of the mice.
The treated mice weighed significantly less than those in the control group, showing slower weight gain.
More important, the treated mice showed greater insulin sensitivity, meaning that their bodies were able to absorb and burn blood glucose and improve their response to insulin.
In a human clinical study, avocatin B given as a dietary supplement to participants eating a typical western diet was absorbed safely into their blood without affecting the kidney, liver or skeletal muscle.
The scientists also saw reductions in weight in human subjects, although the result was not statistically significant.
Having demonstrated its safety in humans, they plan to conduct clinical trials to test avocatin B’s efficacy in treating metabolic ailments in people.
“Although avocados have been touted as a weight-loss food, more research is needed,” Professor Spagnuolo said.
“A healthy diet and exercise are recommended to prevent metabolic disorders leading to obesity or diabetes.”
“We advocate healthy eating and exercise as solutions to the problem, but that’s difficult for some people,” said study first author Nawaz Ahmed, a PhD student at the University of Guelph.
“We’ve known this for decades, and obesity and diabetes are still a significant health problem.”
Nawaz Ahmed et al. Avocatin B Protects Against Lipotoxicity and Improves Insulin Sensitivity in Diet-Induced Obesity. Molecular Nutrition and Food Research, published online October 14, 2019; doi: 10.1002/mnfr.201900688