Have you ever eaten so much that you just can't stand to look at food? If you don't have type 2 diabetes, chances are this happens to you. If you live in the USA, you might have a can't-stand-to-look-at-it reaction to food after Thanksgiving dinner.
But if you are a type 2 diabetic or prediabetic, chances are you keep on wanting to eat the food you see no matter how much your stomach is stuffed.
Doctors at the University of Colorado Medical School and the Denver VA Hospital used MRI scans to measure brain activity in two groups of volunteers:
1. Normal weight people with no health problems.
2. Overweight people who had just finished an 8-week weight loss diet and lost at least 5% of their body weight.
They then invited them to eat six meals prepared by the lab over a two-day period. The meals were "supersized" to provide 30% more calories than the test participants needed.
When the doctors took MRI scans of the normal-weight study participants, they found that the insula and hypothalamus of the brain became less active after two days of overeating. When these parts of the brain are less active, visual cues, that is, looking at food, becomes less attractive. After two days, these participants ate less even when more food was put in front of them.
Overweight and presumably prediabetic study participants, however, had a different reaction. The hunger centers in their brains kept on functioning at the same rate, keeping them hungry whenever they saw food.
This study doesn't tell whether overweight causes brain changes or brain changes cause overweight. However, other research has found that the higher your blood sugar levels, the more your brain stays in "high gear" to keep you eating even more. Many type 2 diabetics can attest that the more they eat, the more they want to eat. The higher their blood sugar levels go, the more they want to eat sugar!
If you have type 2 diabetes, it's very important not to binge on food--ever. And if you do overeat, it's very important to do whatever you have to do, whether it's getting a prescription for medication, exercising more, or forcing yourself to eat much, much less, until your get your blood sugars back in control.
And if you have been on a diet lately, to keep the weight off, keep food out of sight!
Cornier MA, Salzberg AK, Endly DC, Bessesen DH, Rojas DC, Tregellas JR. The effects of overfeeding on the neuronal response to visual food cues in thin and reduced-obese individuals.
PLoS One. 2009 Jul 28;4(7):e6310.