Foods high in trans fats
Many foods with trans fats are popularly consumed worldwide.
In USA greater part of these trans fats come from partially hydrogenated vegetable oils (about 80%), and the average consumption of trans fats from this source has been constant since the 1960′s.
It should be noted that trans fat values must be interpreted with caution because many fast food establishments, restaurants and industries may have changed the type of fat used for frying and cooking since the analysis were done (e.g. on July 1, 2008 in New York trans fats are banned in its 40.000 restaurants).
Foods with trans fats: margarine
Among foods with trans fats, stick or hard margarine had the highest percentage of them, but levels of these fatty acids have declined as improved technology allowed the production of softer margarines which have become popular. But there are difference in trans fat content of margarine from different country:
- the greatest contents are found in soft margarine from Iceland, Norway, and the UK (13-16,5% of total fatty acids);
- less contents are found in Italy, Germany, Finland, and Greece (5.1%, 4.8%, 3.2%, and 2.9% of total fatty acids, respectively);
- in Portugal, The Netherlands, Belgium, Denmark, France, Spain, and Sweden margarine trans fat contents are less than 2% of the total fatty acids.
USA and Canada lag behind Europe, but with advent of trans fat labeling of foods in USA change is occurring. For this reason, at now, in USA margarine is considered to be only a minor contributor of the total trans fats, whereas the major sources are commercially baked and fast food products like cake, cookies, wafer, snack crackers, chicken nuggets, French fries or microwave-oven popcorn (see below).
Foods with trans fats: shortenings
Trans fat content of shortening ranges from 6% to 50% and varies in different country: in Germany, Austria and New Zealand it is less than France or USA.
However like margarines, trans fat content of shortenings is decreasing; i.e. in German shortenings it decreased from 12% of total fatty acids in 1994 to 6% in 1999, in Denmark is 7% (1996) while in New Zealand is about 6% (1997).
Foods with trans fats: vegetable oils
At now, nonhydrogenated vegetable oils for salad and cooking contain no or only small amounts of trans fats. Processing of these oils can produce minimal level of them ranged from 0.05g/100 g food for extra virgin oil to 2,42 g/100 g food for canola oil. So their contribution to trans fat content to the current food supply is very little.
One exception is represented by Pakistani hydrogenated vegetable oils (vegetable ghee/vanaspati) whose trans fat content range from 14% to 34% of total fatty acids.
Foods with trans fats: prepared soups
Among foods with trans fats, prepared soups contain significant amount of them, ranging from 10% of beef bouillon to 35% of onion cream; so they contribute great amount of trans fats to the diet if frequently consumed.
Foods with trans fats: processed foods
Thanks to their long shelf life as their flavor stability, trans fats are used in many processed foods as cookies, cakes, croissants, pastries and other baked goods.
Baked goods are the greatest source of these fats in North American diet. Of course, their trans fat contents depend on the type of fat used in processing. In USA after 2006, when labeling laws were implemented, many processed foods have been reformulated and contain less than 0,5 g of industrial trans fats per serving; so producers can list their content as 0 on the packaging, but it‘s not 0!
Foods with trans fats: sauces
Mayonnaise, salad dressings and other sauces contribute only small or no-amounts of trans fats to the diet.
Foods with trans fats: human milk and infant foods
Trans fat content of human milk reflects the trans fatty acid content of maternal diet in the previous day. In human milk it comprise 1%-7% of the total fatty acids but decreasing from 7.1 in 1998 to 4.6 in 2005/2006.
Infant formulas have trans fat values on average 0.1%-4.5% with a brand up to 15.7% of the total fatty acids.
Baby foods contain greater than 5% of trans fats.
Foods with trans fats in fast foods and restaurants
Shortenings with high amounts of trans fats are used as frying fats, so fast foods and many restaurant’s foods may contain relatively large amounts of them.
Foods with trans fats are fried pies, French fries, chicken nuggets, hamburgers, fried fish as well as fried chicken.
For French fries and chicken nuggets their content varies largely from nation to nation, but also within the same fast food chain in the same country because of the cooking oil used. For example oil used in USA and Peru outlets of a famous fast food chain contains 23-24% of trans fats, whereas oil used in many European countries of the same fast food chain contains about 10% trans fats, with some countries as low as 5% and 1% (Denmark).
On 2006, Stender et al. reported that a meal of French fries and chicken nuggets purchased at McDonald ‘s in New York City contained over 10 g of trans fats, while if purchased at Kentucky Fried Chicken in Hungary they are almost 25 g.
Again, from the work of Stender et all. it can see a cross-country comparison of trans fat contents of chicken nuggets and French fries purchased at McDonald ‘s or Kentucky Fried Chicken: trans fat contents vary depending on the country and even the city and often in the same city.
Chicken nuggets and French fries from McDonald’s:
- less then 1 g in industrial trans fats only if the meals were purchased in Denmark;
- 1-5 g in Portugal, the Netherlands, Russia, Czech Republic, or Spain;
- 5-10 g in the United States, Peru, UK, South Africa, Poland, Finland, France, Italy, Norway, Spain, Sweden, Germany, or Hungary.
Chicken and French fries from Kentucky Fried Chicken:
- less than 2 g in industrial trans fats if the meals were purchased UK (Aberdeen), Denmark, Russia, or Germany (Wiesbaden);
- 2-5 in Germany (Hamburg), France, UK (London or Glasgow), Spain, or Portugal;
- 5-10 in the Bahamas, South Africa, or USA;
- 10-25 g in Hungary, Poland, Peru, or Czech Republic.
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