Grandma's advice may be true after all. Cranberries, long touted as a folk remedy to combat urinary tract infections, may help curb urinary tract infections (UTIs).

A new study confirms that cranberry juice and other cranberry products can help prevent UTIs in some people.

But it may take more than a glass of cranberry juice in the morning to do the trick, and cranberries may benefit some people more than others.

Each year in the U.S., UTIs cause more than 7,000,000 doctor visits and 100,000 hospitalizations, according to statistics cited in the new study, published in the Archives of Internal Medicine.

Urinary tract infections are typically caused by bacteria that enter the bladder or kidneys from the urethra, the tube that carries urine from your bladder. UTIs are more common in women than in men.

Symptoms of UTIs may include:

    Pain or burning during urination
    Frequent urination
    Tenderness in the belly
    Foul-smelling or cloudy urine
    Fever and chills
    Nausea and vomiting


For the study, researchers evaluated the effectiveness of cranberries in preventing UTIs in 13 studies involving more than 1,600 people.

Overall, the results showed that UTIs were 38% rarer among people who used cranberry products (juice or supplements) than those who didn't.

Cranberry products were found to be more effective in preventing UTIs in certain groups of people.

"Cranberry-containing products tend to be more effective in women with recurrent UTIs, [women], children, cranberry juice drinkers, and people using cranberry-containing products more than twice daily," write the researchers, who included Chih-Hung Wang, MD, of National Taiwan University in Taipei, Taiwan.