DNA India
16 August 2010
By Jyoti Shelar
Mumbai, India

Phosphorous and salt, used as preservatives in packaged foods, aggravate kidney problems by more than 50%, warn health experts. According to doctors, kidney patients must stop the intake of these processed foods, as they can increase the severity of the problem.

With an increasing number of patients suffering from chronic kidney diseases (CKD), doctors have been advising their patients to increase the intake of fresh foods, but most people consume packaged foods because they save time.

Dr Umesh Khanna, consultant nephrologist, BSES and Asian Heart Hospital, said: "Packaged foods are time–savers, but they don’t have any vitamins, minerals or other nutrients in them.This makes them unhealthy."

Khanna, who is also chairman of the Mumbai Kidney Foundation, added, "For kidney patients, phosphate is a toxin and we always advocate low phosphorous and other preservatives like salts." The salts are known to cause swellings and an increase in blood pressure.

Besides phosphate,processed foods contain sodium and potassium which are also not recommended for patients.Phosphorus is an essential mineral found in second largest concentration in the human body. "A patient suffering from CKD cannot excrete the phosphorous, because of which it gets accumulated in the body, causing severe harm," said Dr AL Kriplani, professor of nephrology, Bombay Hospital Institute of Medical Sciences, adding that the processed foods are not recommended even for healthy people.

Due to the phosphorous retention in the kidney patients, the parathyroid gland, which controls the amount of calcium in blood and bones, increases in size and function. "In an attempt to raise calcium in the blood, the body extracts calcium from the bones, and eventually the bones are harmed," said Dr Alan Almeida, consultant nephrologist, Hinduja Hospital.

According to Almeida, due to the phosphorous, the blood vessels start becoming stiff, thus compromising the blood supply to the heart and other organs. "Therefore, the kidney patients develop problems related to heart and other organs as well," Almeida said, adding that phosphate binders could be used to avoid the accumulation.

Experts said that high level of phosphorous formed the core ground of severity in kidney patients. While 800 to 1,000 milligrams (mg) of phosphorous a day is the limit for someone who has a kidney disease, the patients do not keep a tab on the amount of intake.

"A lot of our daily foods do contain phosphate. The intake can be controlled by completely avoiding processed foods, which have phosphate in excess quantity," added Khanna.