It’s a shame that the years of iniquitous misinformation, societal pressures, and the promotion of ‘diet culture’ norms, by influencers, the media, ‘health campaigns’ and even friends & family have turned fat, an essential macronutrient into an enemy, sworn to be avoided by all means.
It truly baffles me as to why fat or even just a drop of oil, has been so wrongly accused as an unstoppable thief ready to steal every ounce of progress away from you. But then again. It doesn’t, because when I think back to the times when I would *only eat ‘fat-free yoghurt’, drink ‘skinny lattes’ (a stupid name for a fat-free coffee, if you ask me) or refrain from using peanut butter, or even from drizzling some olive oil on my salad, I too have been there. Terrified of fats.
But this negative portrayal is all so so wrong. Yes, fats are higher in calories (9kcal/gram whereas carbs and protein are 4kcal/gram) and yes saturated & trans fats (i.e. commercially hydrogenated vegetable oils) are detrimental to cardiovascular health and increase levels of LDL-cholesterol (i.e. the ‘bad’ kind of cholesterol), but not all fats are the same.
So yes, you should definitely reduce the crap high in saturated and trans fats, but having said that, it’s equally as important, if not more to include a wide variety of ‘good’ fats (i.e. your essential polyunsaturated fatty acids, high in omega-3s & 6s) within your diet, to benefit from all the amazingness that they provide you with (nutritional gains, cellular & biological functional properties, enhanced flavour, improved texture, satiety and palatability etc.).
So, I’m advising you to eat fats because they’re healthy. But why?
In a nutshell, fats can be categorised according to their functional properties and structure. In simple terms, dietary fat enters your system where it is either,
i. Burnt up and used as an essential fuel source (free fatty acids).
ii. Incorporated into cell membranes for structural & functional integrity, as well as cellular signalling.
iii. Utilised in the biosynthesis of steroid hormones, such as testosterone, oestrogen and progesterone. Therefore if you’re a girl, an adequate amount of fat (both in your diet and on your body) is essential for hormonal balance, a regular period and ovulation! So, if you are post-pubescent and still not menstruating, it’s your body’s way of telling you that you’re just too lean. However, this is just one single contributing factor as *amenorrhoea is a multifactorial condition.
iv. Used to make cholesterol (note – we need some levels of cholesterol in our blood as this is essential for the production of precursor molecules such as 1. bile acids which aid in the digestion of fat droplets, and 2. Eicosanoids, which are chemical messengers essential for recovery and wound healing).
v. In excess, dietary fats can be stored as triacylglyceride (TAG) in adipose tissue i.e. your fat reserves. This is where people tend to get a little stressed out. However, even an appropriate amount of adipose tissue is still required to provide your body with insulation, vital cushioning & protection.
This is just a basic outline, and I’ll try not bore you with too much more sciency stuff, but some understanding may help ease the process of including more fats within your diet and discounting them as ‘fear foods’.
So then, you might be wondering, “Which are the healthiest and most nutritious fats?” and “How much should I be eating!?”
As always, the amount of fat you choose to consume is entirely up to you and should be based upon your individualised needs & personal requirements. However, UK guidelines recommend the following, which I have summarised in the table below.
I just want to quickly touch on the PUFAs (polyunsaturated fatty acids). The ratio you see above i.e. 1:4 for omega-3 & 6 respectively, can easily be obtained by eating approximately 2x 140g portions of fish per week (1 being oily, such as salmon).
However, with that being said I do respect that this isn’t an option for individuals following plant-based or vegan diets. Therefore, if you follow a plant-based diet, I highly recommend taking a daily omega-3 supplement.
The reasoning for this is that many individuals still underestimate their omega-6 intake and overestimate their omega-3 intake. It is much easier to achieve adequate levels of omega-6s, as these are present in most unsaturated plant oils, seeds, nuts etc. However, omega-3 is almost exclusively obtained in sufficient amounts through the consumption of oily fish (i.e. salmon) and marine algae (which evidence suggests isn’t regularly or widely consumed by the average person).
So, as mentioned it’s likely that you’re not getting enough omega-3s, but furthermore an imbalance (or put in other words, super-elevated levels of omega-6 and barely-there omega-3, which could be a concern when following an unbalanced vegan diet) can result in highly detrimental long-term consequences such as delayed cognition, neural & visual dysfunction and damage.
So, what is the functional & biological importance of essential PUFAs obtained through diet?
Omega-6s are metabolised into arachidonic acid (a pro-inflammatory agent, essential for immunity and fighting infection).
Omega-3s are metabolised into EPA, DHA & DPA. EPA and DHA in particular, are anti-inflammatory agents which act as platelet inhibitors, preventing the formation of blood clots/coronary thrombosis and also vasodilators which can reduce the risks associated with developing cardiovascular disease i.e. hypertension. Furthermore, evidence suggests that omega-3 fish oils stabilise the electrical activity of the heart (i.e. anti-arrhythmic), lower TAG levels & correct abnormalities in LDL-cholesterol metabolism, by removing fat from postprandial circulation (which additionally reduces one’s overall cardio-metabolic risk).
That explanation may have been slightly more than you bargained for, but the basic point that I am trying to convey is that the balance (or in this case a ratio of approximately 4:1) for both omega-6 and omega-3 respectively is essential for your body’s protective & recovery systems and is, therefore, an essential component of a healthy & balanced diet.
So, which are the healthier fats & oils to consume based on experience, personal preference and the facts?
In order to gain the most nutritional benefits from fats, it is advised to stick mainly to ‘wholefood’ sources and plant-derived mono/polyunsaturated oils. However, consuming foods higher in saturated fats i.e. eggs, coconut, naturally fermented dairy products (plain full-fat yoghurts and cheeses free from added nasties), lean meats and poultry (turkey, chicken) should NOT be ruled out entirely, as these foods are still extremely nutritious and can form an essential part of a healthy & balanced diet when consumed appropriately!
Now when I say ‘appropriately’ I definitely don’t mean that you should be going around drinking bulletproof coffees and eating buttery egg & bacon cheese rolls on a daily, this is certainly not advisable and can increase post-prandial lipaemia i.e. post-meal fat storage and increased TAG levels.
But all in all, you never just consume saturated fats straight up (unless you’re scooping butter out the tub with a spoon) and dietary cholesterol doesn’t necessarily impact blood cholesterol. The overall quality of the complete food source needs to be factored in i.e. the level of micronutrients, protein content, fermentation etc.)
I am also aware that whole eggs have previously been branded with a bad rep, due to their high-cholesterol content (approx. 200 mg per large egg). However, evidence has disproved this theory (dietary cholesterol contained within eggs is poorly absorbed by humans and therefore does NOT acutely affect LDL-cholesterol status).
So now that that's cleared up, let’s get back to my fav sources of fats & oils.
Saturated fats:
Lean cuts of both red and white types of meat (i.e. turkey, chicken, beef)
Cheese: feta or goats cheese, cottage cheese, brie, camembert, mozzarella (If your diet is already high in saturates, you may want to consider using medium or low-fat cheeses. For instance, I consume a lot of eggs, chicken, fish, yoghurt, coconut, dark choc etc. so to prevent my total fat intake from becoming too high, I usually opt for reduced-fat cheese.)
Yoghurt: natural Greek yoghurt or coconut-based alternatives
Whole eggs
Cocao nibs and coconut shreds
Monounsaturated fats:
Olives
Avocado
Unsalted raw nuts, seeds and nut butters: almonds, cashews, macadamias, pecans, peanuts, sesame and sunflower seeds/tahini
Unrefined/cold-pressed oils: olive, avocado, sesame, macadamia, peanut, high-oleic (meaning high in monounsaturated fats) canola and sunflower seed oil
My personal preferences:
Unrefined and cold-pressed olive oil, which has been scientifically appraised for its beneficial effects on cardiovascular health and dyslipidaemia (i.e. the Mediterranean Diet). Please note that olive oil is heat-labile, therefore shouldn’t actually be used in high-temp cooking (However, I like the taste of veggies sautéed/roasted in olive oil, so it must be done.)
I love baking with extra-virgin cold pressed coconut oil (unrefined), due to its flavour. (Coconut oil is high in saturated fats, in fact, higher than butter. However, some research suggests that it may be one of the few saturates beneficial for raising HDL-cholesterol i.e. the ‘good’ kind, but this is a largely controversial topic, susceptible to bias and with lots of conflicting evidence.). Coconut oil also has a high-smoke point, therefore suitable for high-heat cooking.
Avocado (neutral flavour) and sesame oil (fantastic in Thai and Asian-inspired recipes!). Both have high-smoke points, making them ideal for cooking.
Polyunsaturated fats:
Omega-3s:
Oily fish: salmon, barramundi, fresh tuna, mackerel, shellfish, sardines etc.
Specific nuts & seeds: walnuts, flaxseeds, chia seeds, hemp seeds
Omega-6s:
Seeds: flaxseeds, chia seeds, hemp seeds, sunflower seeds etc.
Nuts: walnuts, pine nuts and brazil nuts
Unrefined/cold-pressed oils: flaxseed and walnut oil
I personally LOVE ALL FISH! But I always make sure to source locally and sustainably if possible. I also love flaxseed & walnut oil (essential to refrigerate after opening) used in dressings (however both these oils are unsuitable for cooking).
So, there you have it. ‘The Truth About Fats’.
My aim here was to ‘clear the air’ and ease any uncertainties or anxiety around fats & oils through an honest and evidence-based approach. As always, I’d love to hear your feedback! So please message me with any comments or queries, and subscribe to join the space, if you haven’t already done so.
*Disclaimer: fats & oils are a pervasive topic. However, this post only focuses on a few key aspects. Health & nutrition is also continually evolving with an array of conflicting and inconsistent information, that can virtually be given out by anyone. So please take care when looking for nutritional guidance and always seek out professional advice first.
Much love,
Cat x
References:
Fard, S.G. Wang, F. Sinclair, A.J. Elliot, G. Turchini, G.M. (2019) ‘How Does High DHA Fish Oil Affect Health? A Systematic Review of Evidence’, Critical Reviews in Food Science and Nutrition, 59(11). Doi: 10.1080/10408398.2018.1425978.
Hayes, J. Benson, G. (2016) ‘What the Latest Evidence Tells Us About Fat and Cardiovascular Health’, Diabetes Spectrum, 29(3). Doi: 10.2337/diaspect.29.3.171.
Liu, A.G. Ford, N.A. Hu, F.B. Zelman, K.M. Mozzaffarian, 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(53). Doi: 10.1186/s12937-017-0271-4.
Scientific Advisory Committee on Nutrition (SACN) (2018) Draft Report: Saturated Fats and Health. London: Public Health England (PHE).
Available at:
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/704522/Draft_report_-_SACN_Saturated_Fats_and_Health.pdf (Accessed: 1 May 2020).
*amenorrhoea – the abnormal absence of menstruation i.e. your period
*RNI Reference Nutrient Intake
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