Jacked Check – An occasional series fact checking the world of bro science
Claim: Regularly eating a large amount of fruit can cause a variety of health issues including gout.
Conclusion: When your body metabolizes fructose, it produces uric acid. Uric acid can form painful crystals in the joints causing gout.
In a previous post, I wrote about my Twitter feud with a fruit fanatic. My point was that I used to consume big fruit salads every day for lunch, and ended up with a raging case of gout in my early 40s.
Since minimizing my fruit intake, I have been gout-free — seven years and counting.
While my tweets and post were directionally correct, I fell short in my technical explanation. It’s not sugar per se that causes gout, but the way the fructose specifically is metabolized by the liver.
My experience in real-life followed exactly what the science would have predicted, and it’s important to elaborate on the medical reasons why.
What fructose does to the body
The body metabolizes types of sugars differently.
The pancreas manages the body’s response to glucose. The organ releases insulin to help cells take in glucose to make energy, thereby regulating blood glucose levels.
The liver, by contrast, is responsible for metabolizing fructose. As a result, fructose does not trigger the release of insulin. (However, fructose is strongly associated with development of hepatic insulin resistance, fatty liver disease, and other metabolic disorders.)
In any event, here’s where the action is: the liver metabolizes fructose through the activation of certain enzymes, which release a waste product called uric acid. The primary cause of gout is elevated uric acid in blood caused by fructose.
A couple thoughts:
- Half the fruit issue is the way scientists and farmers bred small, low-fructose wild fruits into today’s toxic sugar bombs. The other half of the issue is captured perfectly by a meme that occasionally pops up on social media. The caption says: Eat Seasonal Fruit in Moderation vs. The Grocery Store. Above the caption is a picture of the typical supermarket produce section — a vast, vivid ocean of fruit, with mounds of green, red, and gold apples the size of softballs; an overflowing crate of watermelons that each need two arms to be lifted into carts; piles of yellow tropical treats from pineapples to mangos to bananas. This isn’t right.
- My late paternal grandfather struggled with lactose intolerance but loved his breakfast cereal. Rather than use milk in his bowl, he would pour in orange juice instead. We all thought he was a brilliant innovator with a breakthrough solution. Of course, he also suffered mightily from bouts of gout.