Can avocados help us lose weight?
Avocados may be rich in fats but have many dietary benefits. Already recognized for their cardiovascular benefits, avocados may also promote the excretion of fats ingested by overweight or obese people, by modifying their gut microbiota.
Despite their high fat and caloric content, avocados may help us lose weight. Their secret is their richness in fiber and monounsaturated fatty acids (MUFA), which increase satiety and reduce fat levels in the blood. But how does the consumption of avocados impact the bacteria in the gut microbiota and the products that result from the fermentation of ingested food, particularly in obese or overweight people*?
An avocado a day for three months
To answer this question, a team of researchers followed 157 adults aged 25 to 45 who were overweight or obese, but otherwise healthy, for 12 weeks. The subjects were divided into two groups. All were given a meal prepared by the researchers once a day, instead of breakfast, lunch, or dinner. Only one group received a meal containing an avocado, the caloric content of which was matched in the other group. With the exception of the avocado, meal ingredients were >90% similar. For their other meals, the participants were instructed to maintain their usual eating habits and daily serving sizes.
More fat in the stool, less in the body
Results: participants in the avocado group reported MUFA (“good fat”) consumption that was ~20 g higher than the control group, while dietary fiber consumption was 14 g higher. The participants also had a daily caloric surplus of 300 kcal. Despite this, by the end of the study, they had not put on a single ounce. At the same time, their gut microbiota had diversified and was enriched in bacteria able to break down fiber. In addition, their stool contained diminished bile acid concentrations (molecules secreted by the digestive system which make it possible to absorb fats) and more fats. The authors conclude that by modifying the gut microbiota, avocados influence the host metabolism and increase fat excretion. They are already considering new dietary approaches to improve the health of the increasing number of overweight or obese people.
*Overweight is defined as a body mass index (BMI) of 25-30; obesity corresponds to a BMI of >30.
Thompson S. V., Bailey M.A., Taylor A.M. et al. Avocado Consumption Alters Gastrointestinal Bacteria Abundance and Microbial Metabolite Concentrations among Adults with Overweight or Obesity: A Randomized Controlled Trial. J Nutr 2020;00:1–10.