12 February 2021
Have the health benefits of healthy fats been overhyped?
This article was originally posted in the JPS Education Portal – our exclusive subscribers only platform. To join the portal and gain access to more articles, lectures, exercise demos, Q&A’s, click the link HERE and subscribe for just $7.99 per week. Over the past few years, the way in which the general public obtain information has changed…
This article was originally posted in the JPS Education Portal – our exclusive subscribers only platform. To join the portal and gain access to more articles, lectures, exercise demos, Q&A’s, click the link HERE and subscribe for just $7.99 per week.
Over the past few years, the way in which the general public obtain information has changed substantially. The use of social media has grown substantially, and I dare say it has now become the predominant source of health and wellness information for most people.
This isn’t necessarily a step in the right direction considering there is no vetting of information on social media, and anyone from nutritional scientists to my aunt and uncle is free to share information without restriction. Such a situation has resulted in a plethora of false, biased and conflicting information constantly in circulation, confusing the public more than ever.
The controversy of dietary fat.
The topic of dietary fat is one example of suboptimal communication between scientists and consumers, conflicting information from a variety of unsubstantiated sources, and disagreement among the public.
For decades, reducing dietary fat consumption was strongly recommended as a strategy for reducing cardiovascular disease risk. This recommendation was mostly based on the ‘diet-heart hypothesis’ which suggested that consumption of saturated fat and cholesterol played a major role in the development of disease. Dietary fat was demonized heavily for years, and avoidance was advocated. Over time, the general population consensus became dietary fats are bad news.
Explosion of the low-fat movement.
Medical experts at the time pushed the concept that dietary fat was deleterious for your cholesterol levels and heart health. Additionally, consumers were informed that fat was the most calorie-dense macronutrient, increasing the risk of weight gain and obesity.
As a result, in the early twentieth century western culture embraced low-fat dieting culture. Low calorie and low-fat diets were promoted heavily as the solution to leaner, aesthetic bodies (especially for women). Despite the lack of compelling scientific evidence, low-fat diets became the go-to approach for both medical and aesthetic purposes.
The aforementioned belief held unshaken for the better part of the next four decades. Thankfully, due to the advancement and growth of our body of research on the topic, we began to recognize that dietary fat perhaps was not the exclusive variable to blame for the development of heart and metabolic disease, and that previous evidence supporting the low-fat approach had substantial limitations.
On the flip side. Fats are now our friend?
As with most things in our fitness industry, we witnessed a sudden rise in the promotion of dietary fat-mediated “health benefits”, with high-fat products and high-fat diets (e.g., South Beach, Atkins diet) flooding the mainstream. In the same way that many experts peddled the utility of a low-fat dietary approach, a vast number of dietitians, nutritionists, and trainers began advocating the opposite; a high fat diet, with a particular emphasis of consuming many ‘healthy’ or ‘good’ fats.
But what does good or healthy fat actually mean?
Well, here’s how the American Heart Association breaks it down:
Love it: Unsaturated (poly & mono) fats
Limit it: Saturated fats
Lose it: Trans fats, hydrogenated fats, & tropical oils
In other words, the American Heart Association portrayed the message that any unsaturated fats can be consumed without restriction (and that high consumption will in fact improve health markers), and that saturated (animal products) and artificial (trans) fats should be avoided wherever possible.
While this message is very palatable and easily grasped by the general public, it is also grossly simplified, failing to consider nuance, and various other factors involved.
Mainstream dietary fat recommendations.
The current recommendations from recognized and reputable entities such as the American Heart Association, World Health Organization, and the American College of Cardiology all promote very similar guidelines with respect to dietary fat consumption. In regard to total fat intake, they advise consumption should not exceed 35% of total calories, with a minimum intake recommendation of 20% to ensure adequate consumption of energy and essential fatty acids. Moreover, it is strictly emphasized that saturated fats should be kept below 10% of total calories consumed, and that trans fats should be avoided completely. how we should absolutely limit Trans-fat as much as possible. Indeed, this recommendation seems to fit in line with dietary trends detailed in the Australian Health Survey, indicating that this advice has been embraced by the general public.
What does the research say?
These same reputable health entities also conclude that the consumption of monounsaturated fatty acids and polyunsaturated fatty acids is of high importance since they both contribute to the optimal development and functioning of the brain, cardiovascular system, and the nervous system. Interestingly, Jakobsen and colleagues reviewed 11 cohort studies with over 344,000 participants and found that replacing intake of saturated fat with an isocaloric amount of polyunsaturated fats reduced the risk of coronary events and cardiovascular-related mortalities. Similarly, in a meta-analysis, Mozaffarian and colleagues evaluated the effect of increased unsaturated fat consumption in place of saturated fat. Compared to control (who consumed 5% of their calories from polyunsaturated fats), those who consumed an average of 15% of their calories from polyunsaturated fats had a 19% reduced risk of coronary heart disease.
The big problem with healthy fats hype.
It is clear that dietary fats play a significant role in our physiology, influencing the health and function of various bodily systems, including our cell structure, organs and hormones. We also have reasonable evidence that consumption of unsaturated fats is preferable over consumption of saturated and trans fats when it comes to human health and longevity. That being said, when any form of dietary fat is consumed in excess (including unsaturated fats) resulting in the establishment of an unplanned calorie surplus, any potential dietary fat-mediated health benefits vanish. We do have COMPELLING research that a chronic calorie surplus contributing to long term weight and fat gain is the single biggest predictor of early mortality and cardiovascular disease, irrelevant of the proportion of unsaturated fats consumed. This is why I have a slight gripe with many health and fitness “experts” peddling the message that unsaturated or healthy fats should be consumed daily and in high amounts.
It is important to emphasize that fat is a far denser energy source (by double in fact) relative to carbohydrate and protein. Simply advocating for consuming more healthy fats is not very helpful, particularly to a society that struggles to control their overall calorie intake, with 2/3 of people being overweight or obese (in Western cultures at least). For the average Joe, this “healthy fats: LOVE IT” recommendation could (and does often) lead to increased consumption of dietary fat (despite being from “healthy” sources) on a daily basis, resulting in a rapid influx of calories despite a small food volume. Implementing this advice makes the maintenance of a calorie intake conducive to physiological energy demands even more challenging and increases the risk of weight gain (and associated health downsides) substantially. It is well known that positive energy imbalance (i, e., a calorie surplus) leads to obesity. With obesity and chronic weight gain comes an increased risk of numerous metabolic diseases, including diabetes mellitus, dyslipidemia, and hypertension. Of all the external influences on body weight, dietary fat is thought by many, to exert the strongest effect. However – as I hope this piece makes clear – more is not always better.
Simply spreading the message that healthy fats are great can be quite misleading.
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Alice H. Lichtenstein, DSc, Eileen Kennedy, PhD, Phyllis Barrier, MS, RD, CDE, Darla Danford, DSc, Nancy D. Ernst, PhD, Scott M. Grundy, MD, PhD, Gilbert A. Leveille, PhD, Linda Van Horn, PhD, RD, Christine L. Williams, MD, Sarah L. Booth, PhD, Dietary Fat Consumption and Health, Nutrition Reviews, Volume 56, Issue 5, May 1998, Pages 3–19, https://doi.org/10.1111/j.1753-4887.1998.tb01728.x
About the author
Jackson is a PhD candidate, accredited Sports Nutritionist, and competitive bodybuilder and boxer. He currently works at the School of Human Sciences, where he has completed a BSc in Sports Science and in Exercise & Health, and an Honours in Exercise Physiology. Jackson is also completing his PhD in the field of Nutrition where he is directing the first randomised controlled trial investigating the effects of intermittent vs continuous dieting on fat loss, muscle retention and muscle performance in resistance-trained athletes. Instagram @jacksonpeos