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Processed Food and Trans Fat

Processed Food and Trans Fat


(CMA Testing and Certification Laboratories)

Last week (16th Jun 2015) the U.S. FDA announced that food manufacturers will be no longer allowed to use “Partially Hydrogenated Oils” (PHOs) in processed food three years later. The purpose of this determination is to remove “artificial” trans fat from processed food.

“Natural” and “Artificial” Trans Fat

Trans fat present in food can be classified into two types:

1. “Natural” trans fat – naturally present in fat of ruminants (e.g. meat and milk of cattle and sheep / goat)

2. “Artificial” trans fat – formed during partial hydrogenation of vegetable oils i.e. partially hydrogenated oils (main source)


Photo Source: FDA, 2015

Since PHOs can tolerate a higher cooking temperature, and is more stable with a longer shelf-life, they have been widely used in different types of processed foods (e.g. margarines, pastries). Those foods are our major dietary sources of “artificial” trans fat.

Table 1 – Examples of Food which may contain PHOs


Info Source: FDA, 2015

Therefore, FDA’s ban on using PHOs in processed food will greatly reduce the amount of “artificial” trans fat in processed food.

Adverse Health Effect of Trans Fat

Many studies have found that intake of trans fat will lead to increased levels of “bad” cholesterol (i.e. low density lipoprotein cholesterol), and decreased levels of “good” cholesterol (i.e. high density lipoprotein cholesterol). This will result in blockage of blood vessels and increased risks of heart disease.

According to the information from the U.S. Centers for Disease Control and Prevention1,removing “artificial” trans fat from food can prevent 10,000 – 20,000 heart attacks and 3,000 – 7,000 coronary heart disease deaths each year in the U.S. 。


Regulatory Control of Trans Fat in Food

According to the recommendation from The World Health Organization and the Food and Agriculture Organization of the United Nations, dietary intake of trans fat should be less than 1% of daily energy intake.

Although many countries generally agree that trans fat intake should be kept as low as possible, there is no consensus on setting permitted maximum level of trans fat in food. In Denmark, a legal limit of 2 g trans fat per 100 g fat has been set for food. In Singapore, prepacked edible fats and oils for sale or for use as an ingredient in the preparation of foods shall not contain trans fatty acids at levels exceeding 2% (w/w).

Some countries / territories (including United States, Canada, Taiwan and Hong Kong) require mandatory nutrition labels with trans fat declared in pre-packaged food. This requirement allows consumers to make informed choices during shopping.


Photo Source: FDA, 2015


Recently Hong Kong government actively promotes “Hong Kong's Action on Salt and Sugars Reduction” through different platforms and activities, to encourage and help the local citizen to reduce excessive dietary intake of salt and sugars. The ultimate goal is to assist the public to develop and practise a healthy eating habit.

Under the same goal, should the government also do more to reduce our dietary intake of “non-beneficial” trans fat? HK government used to announce that average trans fat contents in four food categories traditionally containing relatively higher levels of trans fat (i.e. cakes; egg tart, pie and pastry; bread; and other bakery products) are going down. This implies that some food companies have voluntarily changed their food formulations to reduce or eliminate trans fat by not using partially hydrogenated oils.

However, in order to further and directly reduce the amount of “artificial” trans fat still found in commercial foods, I think the government should consider adopting the FDA’s new approach on reducing trans fat in processed foods. This shall enable the local citizen to achieve healthy eating.