Most of us have heard of or believe in the old adage that goes like "starve a fever, feed a cold." There is some truth of this, but there is a bit of misunderstanding in this saying. In general, you should feed both a cold and fever and starve neither. When we're sick, we still need our energy, nutrients and liquids in order to battle a sickness. However, studies have found that food deprivation actually stimulates our white blood cells and boosts the immune system. On the other hand, digesting food takes a lot of energy and resources from the body which could instead be used to battle viruses. Yet, not receiving enough nutrients, energy or liquids to ward off sickness can increase infections. While there are arguments that can be made for feeding both ailments, however it's a bit shortsighted to ignore any benefits of "starving" the conditions as well.
How the myth arose
It's believed that the saying may have originated from thoughts about body temperature. Old wives' tales believed that if a person had a cold, the body literally became colder. Thus, in order to warm someone up who was sick with a cold, food was given to them. On the other hand, a person who had a high fever was told to not eat, which was believed to "cool down" the patient's body. While starving is not recommended for treating sickness, the main thing to remember is lots of hydration and getting adequate nutrition. The amount of food needed will differ for adults and children. For kids, one should always feed a cold and feed a fever!
Health myths busted: Don't our bodies need food when we're sick?
The body does need energy to battle off illness. When one consumes healthy food, the body temperature increases, we get extra nutrients, and our energy reserves increase. This is beneficial in fighting colds and fevers. However, food deprivation does have its own set of benefits which can actually be more beneficial than eating when you have a fever. We can drink plenty of water, take vitamins, get a lot of rest when we have a fever, without eating much. In addition, fasting can be very healthy for the body.
Many studies have proven that starving a fever stimulates the production of T cells that help fight off fever-induced symptoms, and that fasting can help boost the immune system to ward off infections. In addition, no studies have found that feeding a fever has been beneficial, except with regards to liquid, energy and nutrition. In either conditions, always drink plenty of (non-sugary) liquids, especially liquids that are nutrient-rich such as vegetable broth or chicken soup. Science has found that in general, fasting is healthy and natural. Above all, get your rest if you have a cold or flu.
The key difference lies in what one is "starving" themselves of. You do not want to starve your body of nutrients or liquids as both are crucial to fight of fevers and colds. It also is not true that you do not require any energy. Avoiding the rich calorie intake derived from foods is what will actually help your fight off a cold or fever. Thus, "starving" would mean using one's stored energy, avoiding high calorie intake, consuming vitamins and having plenty of liquids. For example, have chicken broth instead of chicken.
When we have a fever, our body's immune system goes into overdrive mode to battle the fever. This is why we become hot from all the body heat that is produced in this process. Our digestive system process goes on the back burner. However, if you do feel hungry, do eat. Just avoid excessively heavy, greasy and processed foods that take longer for the body to digest.
Conclusion on "Starve a Fever, Feed a Cold"
A study done in 2002 observed the way that T helper cells reacted in response to food intake and food deprivation. Food intake led to an increase of gamma interferon production in the body, whereas food deprivation stimulated the release of interleukin-4. This means that helper cells stimulated by food deprivation had in fact helped to treat a fever, while those stimulated by food intake aided in cold treatment. Various other studies have found that fasting increases the healthy lifespan of animals, which helps to ward off certain degeneration and illnesses related to aging. This finding implies that not constantly eating is part of our natural eating habits which actually helps to keep us healthy. Regardless of findings and studies, always remember to listen to your body. If you feel hungry, then eat. If you are not sure, then resort to the starve a fever, feed a cold theory.