Thinking about getting in the car to pick up breakfast at a fast-food joint? Hit the brakes and chew on this: High-calorie, high-carb meals – like the one you’re about to chow down – may be driving your gut to leak and accelerating insulin resistance.
We know you’ve heard it before, the Western diet is tied to an increase in diabetes. In fact, 1.5 million Americans are newly diagnosed each year.
UC San Diego School of Medicine researchers used fluorescent peptides to illuminate a molecular mechanism that occurs after consumption of a typical fast-food chain American-style breakfast, one that may be contributing to the prevalence of type 2 diabetes.
The study included sampling blood from 30 volunteers before and after feeding them a breakfast comprised of one McDonald’s Egg McMuffin, two hash browns, a glass of orange juice and one McCafé hot chocolate. Ten participants were healthy, 10 had prediabetes and 10 had been previously diagnosed with type 2 diabetes.
Senior author Paul J. Mills, PhD, professor and chief of Family Medicine and Public Health and director of the Center of Excellence for Research and Training in Integrative Health at UC San Diego School of Medicine, dishes out the study’s key findings.
A high-calorie diet is a major risk factor for the development of type 2 diabetes and is also associated with an increased permeability of the intestinal mucosa or “leaky gut” – a condition that occurs when the barrier function of the lumen (the lining of the intestinal wall) is compromised and allows bacteria, toxins, or in this case digestive enzymes, to seep out of the intestines. We wanted to see if there was a nutritional link.
And the answer is yes. In this study we detail evidence for the hypothesis that the digestive system, and in particular pancreatic proteases (enzymes that break down proteins and peptides – short chains of amino acids – to aid digestion) are significantly increased in the peripheral circulation following a high-calorie meal and may be associated with the development of insulin resistance and type 2 diabetes.
What we found was that before the study participants ate a McDonald’s breakfast, the healthy control group did not have much evidence of protease activity in their blood. People with prediabetes already had a degree of the enzyme activity in their blood and the diabetics had the highest levels of the enzyme activity in their blood.
After eating the high-calorie, high-carbohydrate meal, everyone had increased activity of the enzymes in their blood, but the control group began to return to their pre-meal levels after 30 to 60 minutes. It took longer for prediabetics and diabetics to return to their pre-meal activity levels, and they also had significantly increased activity levels in response to the meal as compared to the healthy group.
When pancreatic enzymes leak into the blood, they don’t turn off their function. They continue to digest proteins and we found that this function included a rapid digestion of insulin receptors, which would make it tougher for people to regulate their glucose. People with diabetes had more of this enzyme activity in their peripheral circulation, independent of these meals, but also a further significant increase and highest response to the meal.
They may have developed their chronic glucose-regulation problem as a result of continued exposure to such high-calorie meals and consequent digestion of their insulin receptors. People with prediabetes may be able to turn this condition around. We have seen that a healthier diet can reverse prediabetes and the molecular activity we saw occurring after eating the high-calories meals may be pointing to the mechanism.
These findings are very consistent with animal studies that Geert Schmid-Schonbein, PhD, UC San Diego Distinguished Professor of Bioengineering has conducted and with the “autodigestion hypothesis” that he developed. Geert Schmid-Schonbein directs the UC San Diego Microcirculation Laboratory – Center for Autodigestion Research at the UC San Diego Jacobs School of Engineering.
In addition to simply avoiding such meals, there are compounds we can take that can inhibit protease activity in the peripheral circulation. Our research team is looking to conduct a randomized clinical trial to see if we can help inhibit pancreatic enzyme activity in the blood and restore insulin receptor integrity, whether through inhibitors or a moderate diet.
The overarching finding is that high-calorie meals that so many Americans eat, especially through different fast food venues, damages intestine integrity so that pancreatic enzymes leak out into peripheral circulation. We should all look at our meals and eat well.
This is something that people can act on today. Things we can do behaviorally to support our health.
Feature Courtesy of UC San Diego School of Medicine