CFS announces First Hong Kong Total Diet Study findings on minerals

The Centre for Food Safety (CFS) of the Food and Environmental Hygiene Department today (December 10) released the ninth report - which is also the last of the series - of the First Hong Kong Total Diet Study. This report is on the dietary intake of the Hong Kong population of 13 minerals, namely boron, calcium, cobalt, copper, iron, magnesium, manganese, molybdenum, phosphorus, potassium, selenium, sodium and zinc. Their associated health risks were assessed by making comparisons with the recommended intakes from international organisations and national authorities.

A spokesman for the CFS said, "The findings showed that among the general adult population, dietary intakes of calcium, iron and potassium were inadequate, while that of sodium was in excess. However, the dietary intake of minerals in the study may be underestimated due to limitations in the research methodologies. Nonetheless, the public should have a balanced and varied diet to prevent inadequate or excessive intakes of minerals."

Minerals are important nutrients for growth, development and normal body functions. Adverse health consequences to the human body can arise from inadequate or excessive intakes of minerals, but it may not lead to clinical symptoms.

According to the findings, in more than 90 per cent of the adult population the dietary intake of calcium was below the recommended intake. Inadequate dietary intake of calcium is one of the important factors causing osteoporosis.

In more than 80 per cent of the adult population the dietary intake of iron was below the recommended intake. Inadequate iron intake might pose health risks such as anaemia and reduced immune function. Young women and pregnant women are more vulnerable to iron deficiency as their requirement of iron is much higher.

The findings also showed that in about 60 per cent of the adult population the dietary intake of potassium was below the recommended intake, while in more than 60 per cent of the adult population, the dietary intake of sodium exceeded the recommended intake. Excessive intake of sodium and inadequate intake of potassium might increase the chances of developing high blood pressure, which might increase the risks of developing stroke and coronary heart disease.

In more than 20 per cent of the adult population the dietary intakes of copper, magnesium, manganese, molybdenum and phosphorus were below the respective recommended intakes, but development of adverse health effects from deficiency of these five minerals is very uncommon. As regards cobalt, boron, selenium and zinc, the dietary intakes of these minerals were within the respective recommended intakes.

The spokesman said, "The public are advised to increase the dietary intakes of calcium, iron and potassium by consuming more food rich in these minerals such as dairy products, beans, vegetables (especially dark green vegetables) and fruit, and a moderate amount of nuts. Pregnant women may consult medical professionals on their requirement of nutrients including minerals (such as calcium and iron)."

The spokesman also advised the public to reduce the dietary intake of sodium. Consumers can take measures such as reducing the use of condiments and sauces like salt, soy sauce and oyster sauce during cooking, ordering food with less salt when eating out, and choosing prepackaged food with low sodium content by reading the nutrition label.

The spokesman advised the trade to clearly declare the nutrition information on the nutrition label for prepackaged foods and to ensure the information is not misleading. Members of the trade are also encouraged to declare the content of individual minerals on the nutrition label for prepackaged foods that are rich in minerals. Food manufacturers should reduce the sodium level in foods and could make reference to the CFS's Trade Guidelines for Reducing Sodium in Foods in doing so.

The First Hong Kong Total Diet Study was launched by the CFS in March 2010 and completed this year. Eight reports have already been released covering the following substances: dioxins and dioxin-like polychlorinated biphenyls, inorganic arsenic, polybrominated diphenyl ethers, pesticide residues, metallic contaminants, acrylamide, mycotoxins, and organochlorine pesticide residues.

The Study aims at estimating the dietary exposure of the general population and various population subgroups to a range of substances, including contaminants and nutrients. The purpose is to assess any associated health risks, focusing on the total diet of the population rather than individual foods.

A total of 150 food items were chosen for the study according to the food consumption patterns of the Hong Kong population. They are being used for testing the levels of over 130 substances including pesticide residues, persistent organic pollutants, metallic contaminants, mycotoxins and minerals. By combining the test results with food consumption data, the dietary exposure of the population to the selected substances may then be estimated.

The full report on the study on minerals is available on the CFS' webpage at www.cfs.gov.hk.

Ends/Wednesday, December 10, 2014