The proverb that people should eat when they have a cold, but not when they have a fever makes some sense intuitively. Since fevers usually only last a day a two and most people tend not to have much of an appetite. Given that colds last for several days, people naturally wish to eat. Is the proverb based simply on ‘gut reaction’ or does it make medical sense.
This is the challenge that Yale researchers set themselves, using a mouse model. Here the researchers looked at the effects of providing nutrients during infection, assessing both bacterial and viral diseases. The outcomes are interesting, according to lead scientist Dr. Ruslan Medzhitov, with a positive effect from not eating with some infections but not with others.
In one round of experiments, mice were infected with the listeria causing bacterium Listeria monocytogenes. The mice naturally did not want to eat and most overcame the disease. However, when the mice were force fed they died. A more detailed study, playing around with different ingredients, showed that death was triggered by food containing glucose, but not when the mice were fed proteins or fats.
The dangerous effect of giving mice glucose could be overcome with a chemical called 2-DG, which prevents glucose metabolism.
Further studies were undertaken using mice infected with an influenza virus. Here the reverse was observed: mice survived when they were force fed glucose, but died when they were denied food (or given the glucose blocker).
The research further suggests that nutrients affect the immune system and how the immune system responds to infection. Dr. Medzhitov outlines: “Almost everything we know about infection is based on immune response studies and looking at how the immune system eliminates pathogens.”
Further research will look further into the interaction between food and disease, and also the role of sleep patterns, as modulators of the immune response.
The research has been published in the journal Cell. The research paper is titled “Opposing Effects of Fasting Metabolism on Tissue Tolerance in Bacterial and Viral Inflammation.”
