There will definitely not be any benefit.
This has been tested on Muslims. The peak of the epidemic just fell on Ramadan, during which, depending on the geographical location, Muslims did not eat or drink for 11 to 20 hours in a row.
Back in mid-April, the World Health Organization published guidelines for Muslims, where it was said that hunger would not hurt the healthy, but it was better for the sick to use their legal right to receive food and water.
But Muslims often do not use this right.
There is a chance that there will not be much harm to immunity from intermittent fasting. This was tested even earlier on HIV-infected Muslims. They missed taking antiviral drugs, but, it seems, in principle, this did not affect their health.
There are also added optimistic publications that limiting fluid intake does not affect the properties of cilia in the respiratory tract. Like everything will work as it should.
Although in the recommendations for the treatment of colds at all times, they separately emphasized additional fluid intake, so that everything was moistened and properly cleaned.
Personally, I got the impression that the few publications that have appeared in the last six months on this topic have been written by Muslim researchers for Muslim readers. There are few publications and they are formulated in the tone "everything will be fine!" Hike, this topic is a little bit... banned in the scientific community.
A few authors argue that fasting can increase the level of cortisol in the blood, and from this the immune system sags a little, and the patient will excrete the virus a little longer. Just a little. Almost doesn't count.
Well, no one, by the way, says that immunity from hunger will jump up sharply.
We have already discussed the story about increasing immunity against viruses in the elderly. There you need to eat well and be sure to get at least 5 servings of vegetables and fruits every day.
So I do not advise you to go hungry.