Each small assault to the tiny blood vessels in our eyes and kidneys and brain that occur when we indulge reduces the function of those organs. In young healthy people, damage is repaired quickly. Not so in older people. We would have patients in our practice show up after Christmas with blurry vision and worse kidney function. And when we asked them what they ate… *

When your body becomes less sensitive to insulin, your blood glucose goes up. Regular binging leads to regular bouts of high blood glucose. High blood glucose damages small blood vessels in the eye and kidney over time (diabetic retinopathy and nephropathy are the largest contributors to blindness and end-stage renal disease in this country). High blood glucose also causes high blood pressure by reducing nitric oxide.

A Single Day of Excessive Dietary Fat Intake Reduces Whole-Body Insulin Sensitivity: The Metabolic Consequence of Binge Eating, Nutrients, 17 August 2017

We know eating big, fatty meals regularly is deleterious:

Consuming excessive amounts of energy as dietary fat for several days or weeks can impair glycemic control and reduce insulin sensitivity in healthy adults.

But what if you only indulge for one day?

One day of high-fat overfeeding increased postprandial glucose area under the curve (AUC) by 17.1% (p < 0.0001) and insulin AUC by 16.4% (p = 0.007). Whole-body insulin sensitivity decreased by 28% (p = 0.001).

In conclusion, a single day of high-fat, overfeeding impaired whole-body insulin sensitivity in young, healthy adults. This highlights the rapidity with which excessive consumption of calories through high-fat food can impair glucose metabolism, and suggests that acute binge eating may have immediate metabolic health consequences for the individual.

Also deleterious.

This study tested high calorie, high fat. What if instead it was high calorie, high carbohydrate?

Whether feeding excess energy in the form of carbohydrates (particularly added sugars, which are also highly palatable) for a single day has the same effect remains unclear. However, overfeeding a carbohydrate-rich diet (40% increase in energy intake; 60% of energy from carbohydrate) for five days was found to elicit changes in skeletal muscle cellular signaling that are typically associated with increased insulin sensitivity. … These data suggest that excessive consumption of dietary fat reduces whole-body insulin sensitivity, rather than a positive energy balance alone.

Eating high calorie, high carbohydrate had a positive effect, it increased insulin sensitivity!

The cohort studied were young, healthy, non-obese males and females who were recreationally active. Older people with chronic diseases would probably have worse outcomes.

It is plausible that the dietary intervention used in the current study may produce a more dramatic effect in populations at risk of developing T2DM (e.g., sedentary, overweight individuals).

Repeated periods of binge eating leads to a progressive worsening of glycemic control. Based on our data, it is plausible to suggest that the metabolic effects of binge eating may have more marked effects in individuals at risk of insulin resistance or the metabolic syndrome.

* The photo up top is a screen cap from the video below. It’s regular fare at the Greenwich Market in London. The sandwich is called “Seriously Cheesy Toastie loaded with Smoked Pulled Pork.”