New Delhi, Dec. 8: A diet rich in potassium, an element found in foods such as bananas, baked potatoes with skin and spinach, has been shown for the first time to protect people from incurable inflammatory bowel diseases.
Indian and American scientists have jointly discovered what they say is a novel, previously unrecognised association between the amount of potassium consumed in everyday diet and the risk of Crohn's disease and ulcerative colitis, inflammatory chronic diseases affecting the small or large intestines.
Their study, published yesterday in the research journal Frontiers in Immunology, has also identified a likely biological mechanism to explain how a potassium-rich diet might suppress the intestinal inflammation induced by the body's own immune system.
"We've seen potassium's protective effect and we think we also know how potassium protects the intestines," Amit Awasthi, an assistant professor at the Translational Health Science and Technology Institute, Faridabad (Haryana), and the study's joint principal investigator in India, told The Telegraph.
In the study, led by Andrew Chan from the Massachusetts General Hospital in the US, the researchers tracked over 194,700 women over many years. They found that those among them who excreted high potassium in their urine -- a signal of high dietary potassium intake - had lower risk of the inflammatory bowel diseases.
Patients with these inflammatory diseases experience abdominal pain or discomfort, diarrhoea with blood or pus, weight loss and fatigue, and other symptoms. Gastro-enterologists estimate that India has about 1.5 million patients with inflammatory bowel diseases.
In laboratory experiments, the researchers also observed that exposure to potassium altered the behaviour of a set of immune system cells called T-cells that can induce the type of inflammation underlying the inflammatory bowel diseases.
"The potassium appears to reduce the inflammatory capacity of these T cells," said Awasthi, whose arm of the study was funded by a joint research alliance between the UK-based Wellcome Trust and the Union government's department of biotechnology.
He said the Faridabad institute was hoping to collaborate with doctors at the All India Institute of Medical Sciences, New Delhi, to explore whether potassium could be used in the management of inflammatory bowel diseases.
"This is an interesting finding, but whether potassium, either through diet or pills, has any effect on decreasing inflammation in patients still needs to be investigated and established," said Vineet Ahuja, professor of gastro-enterology at AIIMS, who was not associated with the study.
Inflammatory bowel diseases are primarily treated through steroids and drugs that can modulate the immune system.
Limited surveys and anecdotal evidence suggests that India is witnessing a rise in the incidence of inflammatory bowel diseases. Some studies have suggested that ulcerative colitis is more prevalent in northern India while Crohn's disease is more common in southern India.