The research and our knowledge of fats has come a long way in over the past 10 years. We’ve gone from fat-phobic, demonising anything ‘high-fat’ and opting for low-fat options to now realising that fats actually should have a place in our diet and are essential for our health. What we understand now is that we can’t disregard all fats as ‘bad’, it’s just about the quality and the quantity of fats that we are consuming.
Fats are essential for the health of our brains, nervous system function, hormone production, skin health, immune function and the absorption of certain nutrients. On average, we know that most of us should be getting approximately 20-35% of our daily macronutrients from a variety of high-quality fats.
Whether it’s eating half an avocado with breakfast, drizzling olive oil over your salad at lunch, cooking with ghee, or snacking on a handful of nuts and seeds in the afternoon, you can easily reach this goal by making sure you include at least one serve of healthy fats at every meal. However, it is important to remember that we are all different and how we respond to fats varies, so some people may find that they respond better with slightly lower or higher amounts of fat in their diet.
Following on from our understanding of the health benefits of fats, there has been a dramatic rise in people following Ketogenic and Paleo-style diets which are based on the principles of eating high-fat and low-carb. It is these diets that developed the famous ‘bullet-proof coffee’ that you’ve probably heard about or seen in your local cafe. Usually, these coffees are made with coconut oil and are said to keep you focused without the pitfalls of normal coffee and help to improve energy function. However, emerging evidence is now suggesting that there may be some health consequences associated with consuming such high amounts of the fats naturally occurring in coconut oil.
The preliminary research we currently have suggests that the long-chain triglycerides in coconut oil may compromise the integrity of the gastrointestinal lining, resulting in a ‘leaky gut’. A leaky gut is where the lining of the small intestine becomes damaged and as a result, in-digested food particles, waste products, bacteria and toxic substances that would usually be contained in the digestive system can leak into the systemic circulation.
How coconut oil is believed to have this action is related to how the long-chain triglycerides in coconut oil are digested. While not yet fully understood, it is hypothesised that the digestion of long-chain triglycerides causes alterations to the tight junctions that support our gut lining and the cells of the small intestine. This increases the permeability of the gastrointestinal epithelium, resulting in a leaky gut. Additionally, the digestion of long-chain triglycerides results in the absorption of molecules called ‘lipopolysaccharides’ or ‘endotoxins’ which able to travel into the systemic circulation, cause chronic low-grade inflammation and a consequently, an increased risk of adverse health outcomes.
Another factor to remember is that the constitution of our microbiome is significantly determined by our heritage, environmental and dietary history. With this in mind, for people from countries that wouldn’t have traditionally been exposed to coconut products, their digestive systems may be even less equipped to cope with processing the fats in coconut oil, potentially having a greater adverse impact in the gut.
It is important to remember that other dietary and lifestyle factors can contribute to leaky gut, and it isn’t just coconut oil that could be responsible. But if you do have a leaky gut, or are consuming lots of coconut oil in excess, it could potentially be making the situation worse.
While this research may be a little confusing and make you once again question the fats in your diet, I want to assure you that this research is NOT suggesting that all fats contribute to a leaky gut and that you should be avoiding fats altogether. If anything this research reiterates what we already know, which is that fats have a place in our diet, but we need to remember that we should be consuming them in moderation and be conscious about the type of the types of the fats we are having.
The predominant fats in our diet should be the omega 3 and omega 6 -rich polyunsaturated and monounsaturated fats (think olives, nuts, seeds and oily fish), with a smaller amount coming from naturally occurring saturated fats (think full-fat dairy products, grass-fed and ethically sourced animal products). While coconut oil can be a part of the diet in small amounts, we know it shouldn’t be the foundations of our diet, it might not be for everyone and you certainly shouldn’t feel you need to add it everything to be ‘healthier’.
If you still want to feel the effects of your bulletproof coffee without having to make it ‘bulletproof’, my recommendation would be to have a normal coffee but enjoy it with, or following a breakfast that contains healthy whole food fats such as eggs, whole yoghurt, olive oil, nuts or seeds.
This is a fairly beefy, complicated topic that we’ve tried to simplify and condense down as much as possible. But if you are interested in getting to the nitty-gritty of the science, here are our references.
Ilbäck, N., Nyblom, M., Carlfors, J., Fagerlund-Aspenström, B., Tavelin, S., & Glynn, A. (2004). Do surface-active lipids in food increase the intestinal permeability to toxic substances and allergenic agents? Medical Hypotheses, 63(4), 724-730. doi:10.1016/j.mehy.2003.10.037
Ghoshal, S., Witta, J., Zhong, J., De Villiers, W., & Eckhardt, E. (2008). Chylomicrons promote intestinal absorption of lipopolysaccharides. Journal of Lipid Research, 50(1), 90-97. doi:10.1194/jlr.m800156-jlr200
Guo, S., Al-Sadi, R., Said, H. M., & Ma, T. Y. (2013). Lipopolysaccharide Causes an Increase in Intestinal Tight Junction Permeability in Vitro and in Vivo by Inducing Enterocyte Membrane Expression and Localization of TLR-4 and CD14. The American Journal of Pathology, 182(2), 375-387. doi:10.1016/j.ajpath.2012.10.014
Laugerette, F., Vors, C., Peretti, N., & Michalski, M. (2011). Complex links between dietary lipids, endogenous endotoxins and metabolic inflammation. Biochimie, 93(1), 39-45. doi:10.1016/j.biochi.2010.04.016