A new study explained that just receiving our food can be enough to make our hunger neurons turn off – in the same way as when we eat. But once the brain realizes food is not imminent, they switch back on fiercely.
Eating smaller meals frequently throughout the day can be the key to resisting the urge to overeat, according to new research.
Scientists analyzed brain scans to understand why we get so excited when we see food come out at a restaurant and so disappointed when it goes to someone else.
The researchers found that eating more meals throughout the day has the potential to keep the brain from jumping at the sight and smell of food by consistently suppressing those hunger neurons, which can lead to eating less and combating obesity.
Eating small meals frequently throughout the day can consistently keep hunger neurons suppressed, according to researchers from the University of Pennsylvania.
Researchers from the University of Pennsylvania sought to distinguish between the biological effects of simply seeing or smelling food and actually consuming food on reducing the activity of the hunger neurons, AgRP.
The brain’s hypothalamus controls the sensation of hunger and is home to neurons known as agouti-related protein-expressing neurons, or AgRP neurons. The team’s previous work conducted on mice, found that those neurons are highly active when an animal is hungry.
But the activity in those neurons declines or is suppressed both when the animal smells food and when they eat it.
Researchers discovered that the only way to keep those hunger neurons down was for the body to receive the calories and nutrients from food.
‘Being hungry can feel unpleasant and these are the neurons that seem to mediate this,’ said J. Nicholas Betley, assistant professor at the University of Pennsylvania.
The new study published in Cell Reports showed that when mice were presented with food, the brain activity rapidly decreased and stayed low during and after eating.
HOW EATING SIX SMALL MEALS A DAY CAN HELP LOSE YOU WEIGHT
Eating six small meals a day has been found to be better for weight loss than eating three large portions. Frequent eating, while keeping calorie intake the same, improves blood sugar levels, according to research from Athens University Medical School.
Regular munching also eases hunger in obese people with, or at risk of, diabetes. Reduced blood sugars suggests better glucose control, resulting in weight loss.
However, experts say there is no one-size-fits-all approach and dieting should be personalized.
But when the mice were exposed to food they were unfamiliar with, in this case a strawberry-flavored, calorie-free gel, the sight and smell had no effect of on their AgRp neuron activity levels.
When the mice ate the gel the hunger nuerons decreased, but it only lasted around 200 seconds.
A second test using a calorie-containing gel showed a decrease in neuron activity that remained longer than when the mice ate the zero-calorie gel.
And after repeated exposure, the mice related the gel with satiety and further tests found their hunger neurons to be suppressed when they saw or smelled it.
‘When these neurons are firing, they’re basically telling you, ”you’d better go get food; you’re starving”,’ said Betley, ‘They’re a sensitive alarm system. And what this study conclusively demonstrated is that nutrients are the primary regulators of this alarm system.’
Betley’s team determined that giving mice a combination of hormones normally released during digestion significantly calmed the activity of these neurons, pointing to a potential therapeutic strategy for reducing overeating and obesity.
While therapies involving these hormones given individually are successfully used in humans, the doses required often lead to nausea.
But the researchers saw no signs of negative side effects in the mice when they were given the cocktail of three hormones, likely because each hormone is given at low doses.
Betley’s team hopes to further explore the ways in which these hormones suppress AgRP neuron activity by looking for a way to trigger their release by mimicking the presence of nutrients in the stomach.
He suggests eating smaller meals throughout the day can suppress the neurons at a consistent level to where the body doesn’t experience a starving sensation.
Previous studies have found that frequently eating leads to better blood sugar control, which is vital to combating diabetes and obesity.
‘Maybe we can develop better combinations of foods or better ways of eating so we can avoid that 9pm binge on Oreo cookies when you’ve had a really great diet all day,’ Betley said.