Talking about constipation may elicit a laugh among certain people, but doctors are just starting to understand how infrequent bowel movements can be a sign of more serious health problems. In Boston, researchers recently found that emergency room visits attributed to constipation had increased from about 500,000 in 2006 to over 700,000 in 2011. And similar studies have shown that frequent abdominal pain in kids may be linked to constipation. With the condition becoming a more prevalent issue in hospitals, research has increasingly looked at its relationship with other conditions, and produced some surprising results.

In a recent study, published in Cell Host & Microbe, researchers from Yale University investigated a possible link between constipation and herpes. Along with her team, lead researcher Akiko Iwasaki, a professor of immunology and investigator at the Howard Hughes Medical Institute, studied mice with herpes simplex virus-1 — the most common cause of genital herpes in the United States. They conducted the study because herpes patients sometimes report unrelated symptoms, such as constipation and the inability to empty their bladder. However, the mechanisms behind these symptoms have long remained a mystery.

Although humans are the only natural host for herpes simplex-1, infected mice still mimic some aspects of the disease — they get urinary bladder infections, for example. For their study, the researchers tracked the disease as it moved throughout the peripheral nervous system, which comprises bundles known as ganglia. From here, they watched as it reached the enteric nervous system, which resides in the gastrointestinal tract.

Their findings showed that once it entered the gastrointestinal tract, it began to kill nerves in the colon. And it’s this damage to the colonic neurons that hinders the movement of food through the digestive tract. The researchers said that if this issue is left untreated, patients could end up with an enlarged colon, which puts them at risk for infection, or gastrointestinal diseases like colitis or colorectal cancer.

"The key finding is that there is this unexpected infection in the neurons in the colon wall after herpes infection," said Iwasaki in a statement. "Other members of the herpes virus family, including Epstein-Barr virus, chicken pox virus, and cytomegalovirus have been found in the neurons of the colon of people with unexplained chronic constipation. When doctors can't figure out the cause of these chronic intestinal conditions, one thing to look at is a viral infection."

Though there isn’t a cure for herpes, the team was able to prevent severe complications and loss of life from constipation by giving the mice a laxative treatment. In addition to laxatives, there are a number of at-home remedies that can improve digestive health and relieve constipation — regardless of whether it’s caused by a sexually transmitted disease, a neurological problem, or just a diet low in fiber.

For those whose diets are low in fiber, simply adding cooked beans to your diet can help to boost intake of the important nutrient. You can also stimulate the digestive tract by drinking a hot cup of coffee, and the magnesium found in dark chocolate can relieve constipation by relaxing muscles in the intestines. Finally, everyone should consider adding a healthy serving of yogurt with probiotics to their diet, as it will promote healthy digestion.

Source: Ralevski A, Horvath T, Iwasaki A, et al. Viral Spread to Enteric Neurons Links Genital HSV-1 Infection to Toxic Megacolon and Lethality. Cell Host & Microbe . 2016.