Updated: Jul 7
‘Good’ fats vs ‘Bad’ fats
When it comes to dietary fats, not all are created equally. While some fats are good for us and promote good health, others can lead to chronic diseases and poor health when consumed excessively.
Research has shown us that healthy fats are extremely necessary and beneficial for the body, including our skin and hair, hormones, brain and nervous system. They are required for the building of cell membranes, muscle movement, reducing inflammation and supporting heart health. Some vitamins actually require the presence of dietary fats in order to be absorbed by the body (fat soluble vitamins A, D, E and K). For the general population, cutting fats completely from the diet does more harm than good.
However, there are types of dietary fat which are harmful to the human body, and it is suggested that foods containing these types of fats should be limited to reduce the risk of developing chronic disease.
It is important to note that fats are the largest source of energy out of the three macronutrients, and they provide more than double the energy content of carbohydrates and protein. Therefore, an excessive amount of fat intake, regardless of the type, will likely lead to excess weight gain. It is important to ensure that nutritious fat-rich foods are still eaten in moderation.
So, what are the different types of fat?
This type of fat includes mono-unsaturated and poly-unsaturated fats which are known as “good” fat. Foods that are rich in unsaturated fat have been shown to prevent cardiovascular diseases, age-related mental decline and Alzheimer’s disease. Including this type of fat in the diet is essential for a well-functioning body and mind. Food rich in unsaturated fat include avocados, nuts, fish such as salmon, tuna and sardines, olives and olive oil, linseeds, chia seeds and tahini.
Saturated fat is found in foods including meat, whole milk, cream, cheese, butter, ghee and coconut oil. There is a great amount of controversy around whether or not saturated fat is as bad as previously believed. Traditionally, research suggested that saturated fat intake was linked to heart disease, however this idea has been called into question more recently. Ultimately saturated fat should not exceed unsaturated fat in the diet, and it should be included in moderation.
This type of fat typically does not occur naturally and is formed artificially through the hydrogenation process of vegetable oils when making processed foods, such as deep-fried foods, biscuits, cakes and pastries, and takeaway foods such as pizza, hamburgers and hot chips. These fats when eaten in excess raise cholesterol levels, and greatly increase the risk of heart disease and other diseases. To optimise long term health trans fats should be minimised as much as possible.
While no foods should be strictly ‘forbidden’ from the diet, it is important to be aware of the different types of dietary fats that exist and their effects on our bodies. Unsaturated fats should be included in greater quantities compared to saturated and trans fats to optimise health.
Dhaka, V., Gulia, N., Ahlawat, K. S., & Khatkar, B. S. (2011). Trans fats-sources, health risks and alternative approach - A review. Journal of food science and technology, 48(5), 534–541. https://doi.org/10.1007/s13197-010-0225-8
Heart Foundation (2021). Fats, oils and heart health. Retrieved from https://www.heartfoundation.org.au/heart-health-education/fats-oils-and-heart-health
Lawrence G. D. (2013). Dietary fats and health: dietary recommendations in the context of scientific evidence. Advances in nutrition (Bethesda, Md.), 4(3), 294–302. https://doi.org/10.3945/an.113.003657
Liu, A. G., Ford, N. A., Hu, F. B., Zelman, K. M., Mozaffarian, D., & Kris-Etherton, P. M. (2017). A healthy approach to dietary fats: understanding the science and taking action to reduce consumer confusion. Nutrition journal, 16(1), 53. https://doi.org/10.1186/s12937-017-0271-4
Nettleton, J. A., Brouwer, I. A., Mensink, R. P., Diekman, C., & Hornstra, G. (2018). Fats in Foods: Current Evidence for Dietary Advice. Annals of nutrition & metabolism, 72(3), 248–254. https://doi.org/10.1159/000488006