Pupils in Hong Kong are eating less sugar, salt, and fat in their lunches and are also consuming too much protein and not enough dietary fiber, according to health officials.

On Wednesday, The Centre for Health Protection and Centre for Food Safety of the city released their findings from the test they conducted on 100 lunchbox samples ahead of the new academic year. These samples were collected from 26 primary schools in January this year.

According to Dr. Anne Fung Yu-kei, the assistant director of health, the results revealed improved nutrient levels among the school lunches of pupils, compared with the last survey five years earlier. What's more encouraging is that the average sodium content per lunch had significantly declined from 951mg in a similar survey in 2013 to 818mg in this test, representing a 14 percent decrease.

 "Total fats, saturated fats, trans fats and sugars in more than 90 percent of the lunch samples were below the upper limits of recommended intake," Fung noted.

According to the South China Morning Post, Hong Kong had close to 600 local, private and international primary schools enrolling about 362,000 pupils in the last school year. Most parents of these pupils are ordering lunchboxes for them from caterers.

Fung noted it would likely take a decade before Hong Kong could reach the desired level of 500mg of salt per lunchbox. The target of health authorities is to reduce sodium levels by 5 to 10 percent every year. Fung added that the best way to help pupils accept less salty fare was to introduce it gradually.

Too much salt intake could increase the risk of hypertension - a risk factor for stroke, heart disease, and other non-communicable diseases.

Meanwhile, officials also found that dietary fiber should be improved in pupil's lunches. According to Fung, 40 percent of the samples were less than the recommended dietary fiber intake - recommended intake is 4g. Dietary fiber is important to prevent cardiovascular diseases, constipation and maintains body weight.

"Inadequate intake will increase the risk of colorectal cancer," Fung added.

The mean protein content, on the other hand, was 21.6g. This is higher compared to the recommended intake of 13.3g. Protein is considered an essential nutrient for growth and development. However, too much consumption can strain the kidneys and liver.

"The problem is probably because of the non-vegetarian lunches," Fung noted. "We found that protein content is 1.8 times the recommended level."

Officials urged to consume more fruits, and suggest schools to encourage parents to pack fruit for their children.