Another reason to cut down salt intake

Do you often drag yourself out of your bed in the middle of the night to take a piddle? While this might seem like a trivial issue, it can lead to irritability, fatigue and stress. After all, who doesn’t enjoy uninterrupted sleep? According to a recent study, cutting down on one’s salt intake can reduce the number of frequent trips to urinate at night. We asked experts if it’s true...

The study

The frequent need to urinate late at night is a condition known as nocturia. Recently, a Japanese team of scientists presented their work at the European Society of Urology conference in London, where in they tracked 321 volunteers for three months and found that reduced salt intake led people to urinate less.

In the study, when 223 volunteers were asked to cut down their salt by 25 per cent, from 10.7g to 8g a day, their average night time toilet visits reduced from an average of 2.3 trips to 1.4 times. But in contrast, when 98 subjects increased their intake from 9.9g to 11g, it was found that the volunteer’s need to urinate increased from 2.3 to 2.7 times a night. The National Health Service in the UK recommends that adults only eat 6g of salt each day.

The study authors also discovered that daytime urination was reduced when salt in the diet was reduced. However, the reduction in nocturnal bathroom visits resulted in a particular improvement in people’s quality of life, they found. Study author Dr Matsuo Tomohiro, of Nagasaki University, said, “This is the first study to measure how salt intake affects the frequency of going to the bathroom,’ adding, “Night time urination is a real problem for many people, especially as they get older. This work holds out the possibility that a simple dietary modification might significantly improve the quality of life for many people.”

Expert speak

“Nocturia is defined as waking up at night to pass urine. Usually more than two voids at night is clinically significant,” says Dr Ruchi Samdani, consultant nephrologist and kidney transplant physician at Jaslok, Saifee and Bhatia Hospital.

Dr Vishwanath Billa, nephrologist, Zen Hospital, who often sees patients with nocturia, approximately 20 patients in a week says, “This is usually noted among elderly males, most of them due to increasing age their prostate gland enlarges and as it enlarges, it irritates the bladder, and for those above 60 with an enlarged prostate have the problem of frequent urination, day or night.” 

Dr Sandeep Patil, physician and intensivist, Fortis Hospitals says, “The prevalence of nocturia is higher with increase in age. It is present in 50 per cent of men and women in the age group of 50 to 59 years. Among those between the age group of 18 to 49 years, it’s more prevalent in women than men. The ratio reverses after 60 years.”

Others are prone too

However, it’s not just the elderly males who suffer from nocturia. “Besides the elderly, nocturia is seen in individuals with lower urinary tract infection, obesity, diabetes, hypertension, coronary artery disease, Obstructive Sleep Apnoea (OSA), Benign prostatic hyperplasia or enlarged prostrate, diuretic usage, antidepressant usage and congestive heart failure,” informs Dr Patil.

Treatment

Treatment is based on the causes, says Dr Billa. If the prostate gland is enlarged, then it can be controlled by medication, sometimes surgery is required. If infection exists, then injections are required. If there’s a hormonal problem, then there are hormone based treatments. Among those with early kidney disease, diagnosis based treatment is recommended. Those facing dietary problems, they should consume less water and salt intake post evening.

Will cutting down on salt help?

The body processes salt through the kidneys. When the intake of salt (sodium chloride) increases, the body responds in two ways — increasing thirst and hence, increasing the liquid intake, and also increasing urine formation to remove the extra salt from the body. Hence, decreasing the salt intake will decrease urine formation and hence decrease nocturia, says Dr Samdani.

The study has shown improvement in nocturia with lowering of salt intake. High intake of salt in the diet leads to water retention. As a result, there could be swelling in the feet. On resting, the fluid enters the bloodstream and excess water from the bloodstream is thrown out of the body by the kidneys. This results in excess urination at night. However, this would benefit in persons with high salt intake and not in other cases like enlarged prostrate and urinary tract infections, says Dr Patil.