Fasting for 24 hours could weaken the immune system

1 year ago 76

Mice that fasted for 24 hours had much inflammation and were much apt to dice from a bacterial corruption than mice connected a regular eating schedule

Health 23 February 2023

By Grace Wade

Fasting has antecedently been suggested arsenic a utile attack for preventing oregon managing chronic diseases specified arsenic cancer, obesity and bosom illness – but results from rodent studies amusement prolonged fasts whitethorn impair the immune system.

Filip Swirski astatine the Icahn School of Medicine astatine Mount Sinai successful New York and his colleagues analysed humor and tissues samples from 5 mice without entree to nutrient for 24 hours. Blood tests comparing these mice with those fixed a regular fare showed that, connected average, the fasting mice had little than 10 per cent of the fig of monocytes – a benignant of achromatic humor compartment that helps combat infections and recruits different immune cells to dainty injury.

“These are the cells that are truly captious ft soldiers of the immune system,” says Swirski. The researchers recovered the alteration was owed to monocytes retreating from the humor to the bony marrow, wherever they fundamentally hibernated, helium says.

As a result, erstwhile the fasting mice were fixed nutrient again, monocytes rushed backmost into their bloodstream. “Because determination is this excess of monocytes that are hibernating and surviving successful the bony marrow, they past longer than they would otherwise,” says Swirski. “So, upon re-feeding, what we spot is simply a surge of monocytes.” Compared with mice that continued to accelerated oregon those that ne'er fasted, these mice had astir 4 times arsenic galore monocytes successful their blood, connected average.

To recognize however this affected immunity, helium and his squad injected 45 mice with a strain of bacteria that infects the lungs. Twenty-three of the mice fasted for 24 hours earlier the injection. The researchers past allowed them to entree food.

After 72 hours, astir 90 per cent of the mice that fasted died, portion astir 60 per cent of the mice that ne'er fasted died. The mice connected restricted diets besides had greater levels of inflammation, suggesting that agelong periods of fasting impair immune responses.

However, Satchidananda Panda astatine the Salk Institute for Biological Studies successful California says that most communal fasting regimens for humans don’t past 24 hours. In fact, his ain probe has shown that a 15-hour accelerated improves immunity successful mice.

Even so, Swirski says these findings are important for however we deliberation astir the duration and implications of fasting. “Like truthful galore things successful life, equilibrium is important. So, what whitethorn beryllium beneficial successful 1 mode could person an unanticipated antagonistic interaction successful another,” helium says.

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