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Fast food: unfriendly and unhealthy


Although nutrition experts might be able to navigate the menus of fast-food restaurant chains, and based on the nutritional information, compose apparently ‘healthy’ meals, there are still many reasons why frequent fast-food consumption at most chains is unhealthy and contributes to weight gain, obesity, type 2 diabetes and coronary artery disease. Fast food generally has a high-energy density, which, together with large portion sizes, induces over consumption of calories. In addition, we have found it to be a myth that the typical fast-food meal is the same worldwide. Chemical analyses of 74 samples of fast-food menus consisting of French fries and fried chicken (nuggets/hot wings) bought in McDonalds and KFC outlets in 35 countries in 2005–2006 showed that the total fat content of the same menu varies from 41 to 65 g at McDonalds and from 42 to 74 g at KFC. In addition, fast food from major chains in most countries still contains unacceptably high levels of industrially produced trans-fatty acids (IP-TFA). IP-TFA have powerful biological effects and may contribute to increased weight gain, abdominal obesity, type 2 diabetes and coronary artery disease. The food quality and portion size need to be improved before it is safe to eat frequently at most fast-food chains.

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SS and JD declare no conflict of interest. AA is medical advisor for Weight Watchers, and is member of several advisory boards for food producers. The Department of Human Nutrition receives/has received research funding from over 50 Danish and international food companies. Otherwise, I declare no conflict of interest.

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Correspondence to A Astrup.

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Stender, S., Dyerberg, J. & Astrup, A. Fast food: unfriendly and unhealthy. Int J Obes 31, 887–890 (2007).

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  • trans-fatty acids
  • fast food
  • energy density

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