(NaturalNews) Scientists have long puzzled over the reasons sleep is so important. Brian Preston from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and an international team of researchers just published research that backs up their theory sleep improves the function of the immune system --and it may specifically protect animals from being overrun by parasite infections.

According to a study just published in the journal BMC Evolutionary Biology, species of animals that get substantial sleep not only have a greater concentration of immune cells in their blood, they also are able to stave off more parasite infections than other creatures. "We suggest that sleep fuels the immune system. While awake, animals must be ready to meet multiple demands on a limited energy supply, including the need to search for food, acquire mates, and provide parental care. When asleep, animals largely avoid these costly activities, and can thus allocate resources to the body`s natural defenses," Dr. Preston said in a media statement.

The scientists studied sleep in mammals, analyzed the animals` immune system measurements, and looked at numbers of infections with parasites. They found mammals that have evolved to have longer sleep cycles have more circulating immune cells and fewer infections with parasites like intestinal worms.

So what do these findings have to do with human health? Possibly, a lot. The researchers conclude: "Given the declines in human sleep durations that have occurred over the past few decades, there is a clear need for studies that further clarify the immunological significance of sleep."

Bottom line: add getting enough sleep to a healthy lifestyle in order to keep your immune system strong and able to fight parasites, which are now throughout the world -- not only in developing countries. For example, according to the Centers for Disease Control and Prevention (CDC), around 14 percent of the U.S. population is infected with Toxocara, or internal roundworms, and some 60million people in the United States are likely infected with Toxoplasma gondii, a parasite associated with raw meat and contact with cat feces. In addition, a report on food borne parasites prepared for the Food Research Institute at the University of Wisconsin in 2003 found about two and a half million cases of food and waterborne Giardia lamblia and three million cases of Cryptosporidium parvum in the U.S. annually. Both these parasites are transmitted through drinking water contaminated with the fecal material of infected persons. The World Health Organization (WHO) ranks parasites as among the six most dangerous diseases that infect humans.

Parasites in humans can cause intestinal discomfort, bloating gas and chronic constipation or diarrhea. Although drugs can be prescribed to kill parasites, many herbs and foods have traditionally been used to treat parasite infections . According to the University of Maryland Medical School web site, these include: raw garlic, pumpkin seeds, pomegranates, beets, and carrots, all of which have antiworm properties.

For more information:
Parasite resistance and the adaptive significance of sleep: http://www.biomedcentral.com/1471-2...
Parasitic Diseases: Often Severe, Nearly Always Preventable: http://www.cdc.gov/ncidod/dpd/featu...
University of Maryland Medical Center Intestinal Parasites Information: http://www.umm.edu/altmed/articles/...

About the author

Sherry Baker is a widely published writer whose work has appeared in Newsweek, Health, the Atlanta Journal and Constitution, Yoga Journal, Optometry, Atlanta, Arthritis Today, Natural Healing Newsletter, OMNI, UCLA's "Healthy Years" newsletter, Mount Sinai School of Medicine's "Focus on Health Aging" newsletter, the Cleveland Clinic's "Men's Health Advisor" newsletter and many others.