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Food Safety Focus (23rd Issue, June 2008) – Incident in Focus

Trans Fats - Part 2

Reported by Ms. Janny MA, Scientific Officer,
Risk Assessment Section, Centre for Food Safety

Trans Fats in Locally Available Foods

In view of growing evidence on the adverse health effects of trans fats intake and increasing concern of their presence in food, the Centre for Food Safety (CFS) and the Consumer Council (CC) have conducted two joint studies on trans fats in locally available foods. These studies aimed to assess trans fats levels in foods available in local market and enhance consumers' understanding of trans fats and their health implications. Results of the latest study were released on 14 May and published in the May issue of Choice magazine. (Please see the hyperlinks at the end of this article for details)

In these studies, the trans fats levels in a total of 165 prepackaged and non-prepackaged food products were evaluated. Although some individual products contained relatively high levels of trans fats, (e.g. a doughnut and two cream-filled breads with shredded coconut), some individual products contained no or relatively low levels of trans fats. Studies also revealed that the trans fats levels varied a lot among the same kind of food. Such results indicated that reduction of trans fats in food was feasible and practical. Consumers can reduce trans fats intake by making informed food choices.

How to Make Informed Food Choices?

Nutrition Labelling - Trans Fats

Under the Food and Drugs (Composition and Labelling) (Amendment: Requirements for Nutrition Labelling and Nutrition Claim) Regulation 2008 (Amendment Regulation), which shall come into operation on 1 July 2010, trans fats are included as one of the core nutrients i.e. all prepackaged foods covered by the Amendment Regulation shall declare the trans fats content on nutrition label. "Trans fats free" claims are also permitted if the prescribed conditions are met.

To include trans fats as a core nutrient not only aligns the Amendment Regulation with the international trend, but also brings about health benefits to the public in the long run. Accurate trans fats value provided on nutrition label and control of trans fats claims on food products may help consumers make informed food choices. To maintain a healthy diet, the intake of trans fats as well as other nutrients including saturated fats has to be taken into account.

Which is a Better Choice?

Which is a Better Choice?

Based on the above information of the three similar products, food C is a better choice as it contains the lowest level of trans and saturated fats. As part of a healthy diet, it is advisable to choose foods low in both trans and saturated fats.

Trans Fats vs Saturated Fats

  Trans Fats Saturated Fats
  • Found naturally in small amounts in milk and fat of cow and sheep
  • Formed in very low level during the refining of vegetable oils
  • Formed mainly when hydrogen is added to vegetable oils under a process called "hydrogenation"†
  • High proportion in most animal fats (e.g. butter, lard, chicken skin, full cream milk, cheese) and some vegetable oils (e.g. coconut oil, palm oil)
Health Effects
  • Increase low-density lipoprotein (LDL) cholesterol, the bad cholesterol
  • Decrease high-density lipoprotein (HDL) cholesterol, the good cholesterol
  • Increase the risk of cardiovascular disease
  • More harmful than saturated fats
  • Increase LDL cholesterol
  • Increase the risk of cardiovascular disease
Daily Recommended Intake Limit
  • Less than 1% daily energy intake‡ (e.g. less than 2.2g in an individual with a daily energy intake of 2 000 kcal)
  • Less than 10% daily energy intake (e.g. less than 22.2g in an individual with a daily energy intake of 2 000 kcal)

Hydrogenation† of Vegetable Oils

During the process of hydrogenation, double bonds in unsaturated fatty acids are turned into single saturated bonds. This process turns liquid oil into semi-solid or solid form and serves the purposes of prolonging shelf-life and changing food texture. Complete hydrogenation would yield 100% saturated fatty acids, however, trans fats would be produced in partial hydrogenation. Some margarines and vegetable shortenings are made of partially hydrogenated vegetable oils.

Energy Intake‡  

The energy intake requirements for healthy individuals take account of age, gender, body weight and physical activity level. According to the World Health Organization and the Food and Agriculture Organization of the United Nations, the energy intake requirements in some healthy adults are as follows:

Age (Years) Male
(assuming body weight of 65kg & low physical activity level)
(assuming body weight of 55kg & low physical activity level; excluding lactating and pregnant women)
18-29 2 400 kcal 1 900 kcal
30-59 2 350 kcal 1 850 kcal
≥ 60 1 950 kcal 1 700 kcal

Since the daily recommended intake limits for trans and saturated fats are in proportion to the recommended daily energy intake requirement, the maximum intake limits for both nutrients are proportionally lower for individuals with a lower energy intake requirement.

Trans Fats:

Quick Tips to Choose Foods with Relatively Low Trans and Saturated Fats

Further Information

Further information about trans fats in foods and recent studies on trans fats in locally available foods can be obtained from the following webpages: