A lot of people believe that fat is harmful and we should avoid when we possibly can, especially when we are on a diet plan. Before we deny fat as a whole, we need to know that there is more than one kind of fat. And different kinds of fat may play different roles in human body.
There is already agreement on artificial trans fat contributes to heart problems and diabetes[2]. The previous popularity of trans fit has been contained in the nation, especially in big cities like New York and Los Angeles[3, 4]. But debates continue on whether saturated fat is harmful and should be replaced with polyunsaturated and monounsaturated fatty acids. There is more evidence we can find in the literature associating saturated fat and cardiovascular disease. A meta-analysis published in 2010 synthesizing 21 prospective cohort studies showed that there is no link between higher saturated fat consumption and increased risk of CVD[5]. The studies chosen were relatively small in size and short in duration and thus studies of larger sizes and more years are still needed to assess the effect of saturated fat. However, on the website of American Heart Association, saturated fat has already been categorized as bad fat along with trans fat[6]. It might be too early to make this judgement based on the available evidence. On the other hand, are there better substitutes than saturated fat? The AHA recommended polyunsaturated fat and monounsaturated fat. A newly published meta-analysis suggests that polyunsaturated fat might be a better option than both saturated fat and monounsaturated fat[7]. Certainly when trans fat goes out, something has to go in to replace it. What will that be? For manufacturers, this is usually saturated fat. The total fat amount in food before and after the trans fat ban did not change.
Low fat is one of the biggest pitfalls about diet. While everybody knows that the excessive body fat contributes to development of chronic diseases, fats (except trans-fat), when consumed in a moderate amount, are actually protective of bones, reproductive health, etc. It is not dietary fat, but the excessive body fat caused energy imbalance through a long period of time that is negatively affecting for public health.
- Sifferlin, A., Here’s New Proof That Not All Fats Are Bad For You. 2016.
- Willett, W.C., Trans fatty acids and cardiovascular disease – epidemiological data. Atherosclerosis Supplements, 2006. 7(2): p. 5-8.
- Angell, S.Y., et al., Cholesterol control beyond the clinic: New York City’s trans fat restriction. Ann Intern Med, 2009. 151(2): p. 129-34.
- McCarthy, M., US gives food manufacturers three years to ban trans fats. BMJ, 2015. 350: p. h3315.
- Siri-Tarino, P.W., et al., Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease. Am J Clin Nutr, 2010. 91(3): p. 535-46.
- Monounsaturated Fats. 2016; Available from: http://www.heart.org/HEARTORG/HealthyLiving/HealthyEating/Nutrition/Monounsaturated-Fats_UCM_301460_Article.jsp#.WBT_MfkrJEY.
- Imamura, F., et al., Effects of Saturated Fat, Polyunsaturated Fat, Monounsaturated Fat, and Carbohydrate on Glucose-Insulin Homeostasis: A Systematic Review and Meta-analysis of Randomised Controlled Feeding Trials. PLoS Med, 2016. 13(7): p. e1002087.
I agree that many people are misled to think that all fats are bad and a “low fat” diet is going to help them lose weight, so it is especially important for practitioners to share this information with their clients. Individuals need to understand the difference in the types of fat, because if someone is uneducated and unfamiliar with health and nutrition, they may not fully understand what the difference is. There are also so many other factors that make something “good” or “bad” that people should also be aware of as well. A food may be high in the healthy fats such as monounsaturated and polyunsaturated fats, but depending on whether it is fried or grilled, for example, this can influence whether or not it is actually healthy. It is useful for practitioners to focus on how to cook food in healthy, delicious ways to make sure individuals are getting the nutrients our bodies need.