Topic for Apr 28 (Mon)

[Kristin55]

Imagined Hunger May Weaken the Immune System

Your body turns food and drink into the energy you need to stay alive. And when you don't have enough food, your immune system gets weaker, meaning your body will struggle to stay healthy and fight infections.

But what if it doesn't just matter how much you've eaten — what if it also matters how much your brain thinks you've eaten?

Researchers from the UK and Italy looked at the effects of two types of neurons that create feelings of hunger and fullness in response to how much energy the body has.

The researchers artificially activated the hunger neurons in the brains of mice, making them feel hungry even after they had eaten. And to their surprise, they found this led to a drop in certain immune cells in the blood that help regulate inflammation.

Inflammation is part of your body's response to things like germs and injuries, and it helps with healing.

The researchers then activated the fullness neurons in mice that hadn't eaten, and found those immune cells returned to normal levels.

In other words, when the brain thought the body was hungry or full — regardless of whether the mice had actually taken in any nutrition — it affected the number of immune cells in their blood.

The researchers further found that when the hunger neurons were turned on, nutrient-sensing in the liver decreased — meaning the brain was affecting how the liver interpreted the body's energy needs.

The researchers said these results challenge the idea that our bodies' immune responses are mainly the result of physical changes in our nutrition, like our blood sugar levels or nutrient intake.

They also said that, if the brain is able to regulate our immune responses in this way, it may be possible to develop new ways to treat diseases just by targeting the brain.

However, they also said more research is needed — especially on how this process works in humans, not just in mice.