Last week, a 26-year-old woman from Arun Khola of Nawalparasi East was rushed to Bir Hospital after her health condition seriously deteriorated. Doctors attending her said that the woman had become too weak and too lean. She was so thin that veins popped up in her arms. Pulse rate could be felt when fingers were placed on her wrist.

“The woman complained that she felt hungry all the time,” said Dr Dipak Malla, a senior consultant endocrinologist at Bir Hospital. “Despite eating heavily, however, she had lost significant weight. Her eyes were bulging, red and constantly tearing up. She also had visible swelling in the neck and goitre.”

Tests showed excessively high levels of T3 (triiodothyronine) and T4 (thyroxine), and critically low levels of TSH (thyroid-stimulating hormone)—tell-tale signs that the woman was suffering from hyperthyroidism.

T3 and T4 hormone levels rise due to high intake of iodine or production of TSH receptor antibodies, Dr Malla said.

Doctors say that in hyperthyroidism, the thyroid gland produces more thyroid hormones than the body needs. When iodine intake is too high, it can sometimes trigger or worsen hyperthyroidism in sensitive persons. Excessive iodine intake may overstimulate the thyroid gland, leading to increased hormone production.

In people who already have thyroid nodules or conditions like Graves’ disease or autoimmune disease, high iodine intake can make the overactive thyroid worse, and also causes increased production of T3 and T4 hormones.

The records at the country’s largest Bir Hospital show over 60 patients with hyperthyroidism visit for treatment on a daily basis.

Doctors say those with hyperthyroidism suffer from a rapid heartbeat, which could reach over 200 per minute. The condition also triggers severe weight loss in patients even if they eat a lot, rapid trembling in the hands and fingers. Those with the condition also experience difficulty sleeping.

Some women suffer from heavy bleeding during menstruation. Some could also suffer from anxiety, while some have enlarged thyroid glands. Severe hyperthyroidism triggers excessive thyroid hormones, which can overstimulate the heart beat and lead to sudden deaths.

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A nationwide survey conducted a decade ago—the Nepal Micronutrient Status Survey-2016—found Nepalis’ diet has an excessive amount of iodine.

The survey was jointly carried out by the World Health Organisation, UNICEF, the US-based Centres for Disease Control and Prevention, and the then Ministry of Health and Population.

The study showed that over two-thirds—68 percent—of the population across the country is consuming iodine in excess of the recommended level—more than 40 ppm. Among all salt samples collected for the study, over nine in ten (91 percent) had iodine levels more than 15 ppm, while four percent did not have any iodine—which is less than 5 ppm.

The Non-communicable Disease Risk Factors: Steps Survey-2019 showed that 5.6 percent of adults (6.5 percent of women and 4.6 percent of men) reported adding salt often or always to food right before or while eating. Moreover, 19.5 percent of adults (18.1 percent of women and 21.1 percent of men) reported consuming processed foods that are high in salt often or always.

The UN health agency recommends less than two grams of sodium, or five grams of salt, per day for adults to reduce blood pressure and cut the risk of cardiovascular disease and stroke. It also recommends policies to reduce salt intake, including food product reformation, establishing a supportive environment in public institutions, organising communications and mass media campaigns, and front-of-pack labelling, among other things, to prevent and control non-communicable diseases.

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Iodine, an essential mineral for the body, is added to salt, a staple in Nepali kitchens. The Salt Trading Corporation, the agency responsible for importing and distributing salt in Nepal, fortifies salt with iodine at 50 ppm (parts per million) per kilogram—higher than the recommended level. The World Health Organisation recommends an iodine concentration of 15 to 40 ppm in salt.

Iodine fortification in Nepal began in the 1990s following reports of iodine deficiency disorders, including goitre. While goitre cases have since declined, doctors say cases of hyperthyroidism have increased.

Officials said the higher iodine level was mandated in the 1990s under the assumption that transport and storage times were longer; back then, salt had to be carried on the backs of men and horses, mules, and donkeys. Some amount of iodine would therefore dissipate by the time the salt reached markets. Moreover, back then, people used to store salt openly.

However, with roads now reaching almost all corners of the country, transport times have considerably decreased. There is no longer the need for such a high level of iodine in salt, doctors say.

Multiple endocrinologists the Post spoke to said cases of hyperthyroidism have increased manifold over the past decade, which they mainly attribute to high iodine levels. “The numbers are so high that I am busy attending patients from morning to evening,” said Dr Mahesh Dahal, an endocrinologist at Clinic One.

In the past, various agencies concluded that it was already too late to implement a policy to set an upper limit on salt’s iodine content.

In 2024, a high-level meeting comprising representatives from the World Health Organisation, UNICEF, officials from various government ministries, including the Ministry of Agriculture and Livestock Development, the Department of Food Technology and Quality Control, and researchers from Tribhuvan University had agreed on a proposal to set an upper limit of iodine content in salt.

Health officials tasked the Department of Food Technology and Quality Control with incorporating experts’ suggestions and forwarding the proposal to the Cabinet to lower the salt’s iodine content.

Officials said they had also included evidence from various national and international studies, details on iodine content in salt in other countries, and a comparison of salt intake in Nepal with that in other countries.

In October 2024, the government sent a nine-member team, led by the then-director general of the Department of Food Technology and Quality Control, to Gujarat, India, to study the iodine fortification process.

“During the visit, we found that the level of iodine fortification in salt meant for India is lower than that prepared for Nepal,” said Lila Bikram Thapa, chief of the Nutrition Section at the Family Welfare Division under the Department of Health Services. “We had prepared a report and furnished it to the agencies concerned.”

Authorities have yet to made a decision.

Health officials say they had planned to decide whether to lower the iodine content in salt only after a micronutrient status survey, which was scheduled to start in 2025. But the planned study was postponed indefinitely following the US government’s suspension of all USAID-funded programmes worldwide, including in Nepal.

Experts say that if the high iodine content in salt is causing more harm than good, the relevant authorities should not wait for further results before making a decision.

“Reduction of iodine content in salt must be discussed soon,” Dr Dahal, the endocrinologist, said. “And an appropriate decision must be taken.”