Once upon a time, avocados were rare. The first time I saw one, back in the mid-1960s in New England, I didn’t know what it was. But I remember how ugly and creepy it seemed to look to me.
Our neighbor was in the wholesale produce distribution business down at the Boston Market, and he occasionally brought us rare fruits like avocados. A few years later, when I lived in California, avocados were more common because they grew there. But they weren’t popular, and it wasn’t easy to make money growing them.
In fact, our next-door neighbor, a practicing physician, also grew avocados on his “ranch” in the California foothills as a tax shelter (because he could show a loss while getting some agricultural subsidies). He needed to irrigate constantly in that natural desert land, and he paid my brother and me to haul miles of irrigation pipes on a flatbed truck up to the ranch (resulting in a scar on my shin that still looks ugly today).
One reason avocados were so unpopular back then is because they were considered unhealthy. Unlike other fruits, they contain fats. And in those “dark ages,” the medical myth was that all fats were the same: All fats had too many calories and all fats were “bad.”
Of course, it slowly became understood that avocados are rich in healthy, essential fats. And research now shows that regular avocado consumption lowers blood fats and makes you feel full without consuming excess calories, thanks to their fiber content.
Indeed, avocados are also loaded with fiber—a key prebiotic that feeds the probiotics (“good” bacteria) in your gastrointestinal (GI) microbiome. And probiotics are not only essential for cognitive health (as I explained on page 3), but for overall good health and immunity.
Plus, a new study shows that eating an avocado a day can actually increase the amount and diversity of probiotics in your microbiome.
(Perhaps because the human GI system can’t break down healthy fiber on its own, but instead relies on probiotics to do so. And this study shows that avocados provide a double benefit by supplying the fiber and supporting the probiotics that allow us to digest that fiber!)
Researchers recruited 163 adults, ages 25 to 45 years, who were overweight or obese but otherwise healthy. Participants were divided into two groups. And during a 12-week period, one group was fed a meal each day that included an avocado—whereas the other group consumed the same meal, without an avocado.
Samples of blood, feces, and urine were collected throughout the study period. Every four weeks, participants also recorded diaries of everything they ate.
At the end of the study, the researchers found that the group that ate the daily avocados had higher levels of three key probiotic strains in their feces. Strongly indicating that, along with their healthy fat, fiber, and potassium content, avocados also support healthy probiotics in the GI tract.
So, as I always recommend, skip the useless probiotic pills (they don’t work anyway). Instead, eat a healthy, balanced diet with plenty of prebiotic foods—like the humble, “ugly” avocado.
“Avocado Consumption Alters Gastrointestinal Bacteria Abundance and Microbial Metabolite Concentrations among Adults with Overweight or Obesity: A Randomized Controlled Trial.” The Journal of Nutrition, 2020, nxaa219.