Why skipping breakfast can compromise the immune system

Diet profoundly influences people’s health. And just as overeating increases the risk of disease through its influence on immunity and metabolism, calorie restriction and fasting They don’t seem to be as beneficial as you might think.

According to a recent study by researchers at the Icahn School of Medicine at Mount Sinai, fasting can be harmful to fight infection and could lead to an increased risk of heart disease.

The survey, the results of which were published in the February 23 Immunity, focused on mouse models and is one of the first to show that skipping meals triggers a response in the brain that negatively affects immune cells. According to the researchers, their findings could provide insight into how chronic fasting can affect the body in the long term.

“We have identified a fasting-induced change in leukocyte migration that prolongs monocyte lifespan and alters disease susceptibility in mice,” the paper’s authors noted when publishing their findings. We show that fasting during the active phase induces the rapid return of monocytes from the blood to the bone marrow.”

In the study, the researchers sought to better understand how fasting, from a relatively short fast of a few hours to a more severe 24-hour fast, affects the immune system. To do this, they analyzed two groups of mice: one group had breakfast immediately after waking up and the other group didn’t. The researchers took blood samples from both groups when the mice woke up, then four hours later and eight hours later.

When reviewing the lab results, they noted a clear difference in the fasting group. Specifically, the researchers saw a difference in the number of monocyteswhich are white blood cells that are made in the bone marrow and travel throughout the body, where they perform many essential functions, from fighting infection to heart disease and cancer.

Filip Swirski is the study’s lead author, Ph.D., and director of the Cardiovascular Research Institute at Icahn Mount Sinai, noting that “there is a growing awareness that fasting is healthy and, in fact, there is ample evidence of the benefits of fasting.” Our study offers a caveat, as it suggests that fasting can also come at a cost that carries a health risk -he pointed-. This is a mechanistic study that looks at some of the fundamental biology related to fasting. The study shows that there is a conversation between the nervous and immune systems.

The work is one of the first to establish the connection between the brain and these immune cells during fasting. The researchers found that specific regions of the brain controlled the monocyte response during fasting, so they concluded that “fasting causes a stress response in the brain, that’s what makes people hungry, what triggers instantaneous large-scale migration of these white blood cells from the blood to the bone marrow and then back into the bloodstream shortly after reintroduction of food.

And while Swirski pointed out that there is also evidence for the metabolic benefits of fasting, he noted that this new study is a useful step forward in fully understanding the mechanics of the body.

“The study shows that, on the one hand, fasting reduces the number of circulating monocytes, which could be considered a good thing, since these cells are important components of inflammation. On the other hand, the reintroduction of food creates a surge of monocytes that flow back into the blood, which can be problematic.”

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