Avocados are considered a healthy food because they contain high amounts of beneficial dietary fiber and monounsaturated fats. Eating avocados provide people with a sense of fullness, and studies have also shown that consuming avocados can lower blood cholesterol levels.i However, researchers at the University of Illinois wanted to learn what impact avocados might have on the bacteria in the gastrointestinal system.
For this study, 163 overweight or obese men and women were selected and divided into two groups similar in age, sex, amount of belly fat, and fasting blood sugar levels. The researchers provided the two groups of participants with one meal daily for 12 weeks. Although the meals contained the same number of calories, one meal contained an avocado, whereas the control group’s dinner contained no avocado.ii
RESULTS: Ingestion of avocados resulted in significant improvements in the composition of the gut microbiome. There was a greater abundance (from 26% to 65%) of several bacteria strains known to ferment fibers efficiently. Ingestion of avocados also resulted in a greater production of short-chain fatty acid postbiotic metabolites. Another significant benefit from ingestion of avocados was a large decline in levels of bile salt metabolites, which are associated with an increased risk of colon cancer. There was a 91% reduction in cholic acid and a 57% reduction in chenodeoxycholic acid.iii
This study explains that the health benefits associated with ingestion of avocados are due to beneficial changes in the composition of the gut microbiome and postbiotic metabolites’ production.
Colquhoun DM, et al. Comparison of the effects on lipoproteins and apolipoproteins of a diet high in monounsaturated fatty acids, enriched with an avocado high-carbohydrate diet. Am J Clin Nutr. Oct 1992;56(4):671-677.
Thompson SV, 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 Aug 17;nxaa219.
Ajouz H, et al. Secondary bile acids: an underrecognized cause of colon cancer. World Journal of Surgical Oncology. May 24, 2014;12:164.