Feed a cold and starve a fever: Gran was right!

THE traditional advice to feed a cold and starve a fever may be more than an old wives’ tale, research has found.

Scientists have shown that food helps animals to recover from a virus – while starving them hastens their death.

And with the food-poisoning bug, they found the opposite was true – with animals that did not eat recovering and those that ate dying.

Professor Ruslan Medzhitov, who led the research, said: ‘We were surprised at how profound the effects of feeding were, both positive and negative.

‘Anorexia – not eating – is a common behaviour during sickness that is seen in people and all kinds of animals. Our findings show that it has a strong protective effect with certain infections but not with others.’

In the first of a series of experiments by Professor Medzhitov’s team at the Yale School of Medicine in the US, mice were infected with the flu virus.

Those that were then forced to eat lived, but those denied food died.

The common cold, flu and chicken pox are all caused by viruses, so fit the adage that it is good to ‘feed a cold’. In contrast, mice infected with the listeria bacteria reacted very differently.

The food-poisoning bug caused the creatures to lose their appetite. But they went on to recover despite their self-imposed starvation.

However, when they were made to eat, they died. Further research showed sweet food to be the killer.

The mice survived when they were fed protein or given fat.

But sugar caused a fatal reaction, the journal Cell reports. Bacterial and viral infections activate different parts of the immune system and it is thought they have different metabolic needs. If they are not satisfied, recovery could be more difficult.

The researchers now want to investigate why people sometimes display food cravings when they are sick.

They say the work could help improve the treatment of sepsis, a potentially fatal type of blood poisoning triggered by an infection.

Various treatments are available but the condition kills 40,000 Britons a year – more than breast, bowel and prostate cancer combined.

It can be sparked by a virus or bacterium, so something as simple as tailoring a patient’s feeding to the cause could help their recovery.

Professor Medzhitov said: ‘A number of studies have looked at nutrition in patients with sepsis, and the results have been mixed.

‘But these studies didn’t segregate patients based on whether their sepsis was bacterial or viral.’

‘It has a strong protective effect’