Beijing residents should continue to consume salt added with iodine element, a mandatory measure in many parts of China, to combat diseases caused by iodine deficiency, a health expert said.

These diseases were common in the last century, but have largely been eliminated in Beijing, due to consumption of salt with iodine element, according to Xie Hui, an official at Beijing Centers for Diseases Control and Prevention.

"Monitoring results in recent years show that iodine nutrition among Beijing residents is satisfactory," Xie said on Wednesday at an event to mark China's 20th Iodine Deficiency Prevention Day.

"However, research shows about 70 to 80 percent of iodine residents take every day comes from iodine-added salt," Xie said. "Therefore, residents should continue to consume iodine-added salt to avoid iodine deficiency."

Yang Xueming, a professor with the China Endemic Diseases Society, echoed her advice.

"Iodine is lacking in Beijing's natural environment, including water and soil, and adding iodine is the most efficient way for people to make up for deficiency."

Salt added with iodine has been promoted across China since 1994, resulting in a dramatic decrease in diseases caused by iodine deficiency across the country, such as thyroid swelling and in neuron damage.

Yang discounted rumors of iodine intake.

"There is no evidence to prove excessive intake of iodine can lead to thyroid cancer, but deficiency of iodine can cause many diseases."