Study Identifies Brain Mechanism Which May Explain Glucose Cravings


Source: Journal of Clinical Investigation

According to a recent study at Imperial College London, an enzyme in the brain called glucokinase may drive our desire for glucose-rich starchy and sugary foods.

Glucokinase is present in the hypothalamus and detects glucose in the liver and pancreas. Dr. James Gardiner of the Department of Medicine lead the study and noted, “This is the first time anyone has discovered a system in the brain that responds to a specific nutrient, rather than energy intake in general. It suggests that when you’re thinking about diet, you have to think about different nutrients, not just count calories.”

Published in the Journal of Clinical Investigation, the team noted the discovery could help develop methods to reduce glucose cravings in humans, including dietary changes and development of obesity treatment drugs.

“Appetite for glucose is an important driver of overall food intake,” the researchers wrote, adding that although glucokinase’s role in appetite has been suggested previously, it had not been demonstrated.

The study authors found that glucokinase activity in rats’ brains was low following a 24-hour fasting period. When they stimulated glucokinase activity using a virus in a separate experiment, the rats consumed more glucose instead of their regular food. When glucokinase activity was decreased, they consumed less glucose.

The researchers suggested this indicated glucokinase is involved in desire for glucose, a main component of carbohydrate-rich sweet and starchy foods. They suggested that when the brain detects that it is not receiving enough glucose, this mechanism prompts animals to seek more.

Referring to the study’s relevance for humans, Gardiner said, “People are likely to have different levels of this enzyme, so different things will work for different people. For some people, eating more starchy foods at the start of a meal might be a way to feel full more quickly by targeting this system, meaning they eat less overall.”

The study was funded by the Biotechnology and Biological Sciences Research Council.

Article from Food Navigator

(Study authors: Syed Hussain, Errol Richardson, Yue Ma, Christopher Holton, Ivan De Backer, Niki Buckley, Waljit Dhillo, Gavin Bewick, Shuai Zhang, David Carling, Steve Bloom, and James Gardiner)