Starve a Fever?

You've all heard the old adage, "Feed a cold, starve a fever." Many websites claim that this adage is just a myth (see here or here).

I fortuitously stumbled across this study, the purpose of which was to show that eating simple carbs (such as sugar) brings down the body's ability to scavenge for harmful bacteria (namely, Staphyloccus epidermidis, a very common bacteria that causes fevers or even fatal meningitis).

Notice the last sentence of the abstract, which shows that a 36- or 60-hour fast also improved the body's ability to fight off staph bacteria:

American Journal of Clinical Nutrition, Vol 26, 1180-1184, Copyright © 1973

Role of sugars in human neutrophilic phagocytosis

Albert Sanchez, J. L. Reeser, H. S. Lau, P. Y. Yahiku, R. E. Willard, P. J. McMillan, S. Y. Cho, A. R. Magie, and U. D. Register

1 From the Departments of Nutrition, Biostatistics, and Environmental Health in the School of Health, and the Department of Microbiology, Pathology, and Anatomy in the School of Medicine, Loma Linda University, Loma Linda, California 92354

This study was designed to test a) whether carbohydrates other than glucose decreased the phagocytic capacity of neutrophils in normal human subjects, b) the duration of this effect, and c) the effect of fasting on neutrophilic phagocytosis. Venous blood was drawn from the arm after an overnight fast and at 0.5, 1, 2, 3, or 5 hr postprandial and this was incubated with a suspension of Staphylococcus epidermidis. The phagocytic index (mean number of bacteria viewed within each neutrophil) was determined by microscopic examination of slides prepared with Wright's stain. Oral 100-g portions of carbohydrate from glucose, fructose, sucrose, honey, or orange juice all significantly decreased the capacity of neutrophils to engulf bacteria as measured by the slide technique. Starch ingestion did not have this effect. The decrease in phagocytic index was rapid following the ingestion of simple carbohydrates. The greatest effects occurred between 1 and 2 hr postprandial, but the values were still significantly below the fasting control values 5 hr after feeding (P < 0.001). The decreased phagocytic index was not significantly associated with the number of neutrophils. These data suggest that the function and not the number of phagocytes was altered by ingestion of sugars. This implicates glucose and other simple carbohydrates in the control of phagocytosis and shows that the effects last for at least 5 hr. On the other hand, a fast of 36 or 60 hr significantly increased (P < 0.001) the phagocytic index.

More recently, there was a small study that tended to confirm "feed a cold, starve a fever."

The maxim "feed a cold, starve a fever" may be right after all, researchers have discovered.

Until now, most doctors and nutritionists have rejected the idea as a myth. But Dutch scientists have found that eating a meal boosts the type of immune response that destroys the viruses responsible for colds, while fasting stimulates the response that tackles the bacterial infections responsible for most fevers.

"To our knowledge, this is the first time that such a direct effect has been demonstrated," says Gijs van den Brink of the Academic Medical Center in Amsterdam.