Foods that provide fat offer a concentrated source of dietary energy – a source of fuel needed for survival. We desire dietary fats biologically and socio-culturally, and they contribute flavour, texture, and aroma that keeps us coming back for more.
Concern around dietary fat intake is more complex than simply running from any fatty food for fear of weight gain or other chronic diet-related health conditions. For health and happiness, there are fats to limit, and fats to embrace.
We love including good nourishing sources of fat in our daily diet here at That Sugar. These can include avocado, olive oil, nuts, seeds and some oily fish.
But there is one type of fat that gets an all-resounding no-no for consumption – trans-fats.
The down-low on trans-fats
Now, a little trans-fat exists in some foods naturally, like in dairy fat. That is fine, and not what we are concerned with here.1
However, when we get stuck into foods that are comprised of industrially produced partially hydrogenated processed vegetable oils, we can overload on the trans, and experience detrimental effects on the body.
Trans-unsaturated fatty acids (a.k.a trans-fats) are created when hydrogen is added to vegetable oils to make them more structurally similar in shape to saturated fat, and therefore solid at room temperature, less likely to go rancid, and good for frying.
Manufacturers LOVE it. It is perfect for replacing animal fat, making doughnuts or fried chicken, and keeping those cookies on the supermarket shelf for several years without spoiling.1
But the altered structure of artificially created trans-fatty acids can be dangerous, and may hinder our ability to metabolise beneficial essential fatty acids.2
Such trans fats have been associated with increased risk of cardiovascular disease, lowering HDL (the good) and raising LDL (the not-so-good) cholesterol, damaging endothelial lining of blood vessels, and inflammation.1;3-6
As a result, we are working toward removing manufactured trans-fats from our food supply – but also make sure to keep an eye out for hydrogenated vegetable oils in the ingredients lists, trans-fats in the nutrition panel, and limit foods like pastries, pies, cookies, cakes, and fried foods.1
Nasty fat aside, what we need is to choose ourselves some good fat!
Essential fatty acids
As the name implies, these are essential to our survival. Essential fatty acids (EFA) are polyunsaturated fatty acids, with the most common forms being omega-3 and omega-6.
Omega-3 fats are sourced from foods such as walnuts, flaxseed, chia seed, oily fish, and leafy greens. And what has gained omega-3 fats such positive attention of late is its anti-inflammatory activity, and nourishment it offers the brain, joints, heart, the nervous system and more.7
Omega-6 fats are commonly sourced from seed oils, as well as whole foods like seeds, grains, dairy, and meat. It offers helpful inflammatory and anti-inflammatory activity, maintains the reproductive system and bone health, regulates metabolism, and ideally is consumed in 1:1 or 2:1 ratio with omega-3 fatty acids.8-9
However, it is estimated the ratio of omega-6 to omega-3 fatty acids intake is 16:1.8 Yikes.
Too much omega-6 – as we are seeing in the Western style diet that comprises a LOT of highly processed foods that contain a LOT of industrialised seed oils – and inflammation can spiral out of control. We need a little less of the omega-6 and a little more of the omega-3 to balance out the inflammatory response.
Monounsaturated fatty acids
Olive oil is the poster-child of the mono-fats, and a diet that includes whole food or minimally processed sources, like olives, olive oils, avocado, peanuts and almonds, may reap health benefits. Studies are correlating the health benefits of the Mediterranean style diet, often high in whole foods and monounsaturated fats, with lowered risk of conditions like type 2 diabetes and cardiovascular disease.4;10
Saturated fatty acids
There remains much conjecture over whether saturated fats are not too great for us or are a welcome part of a balanced, whole food diet.
Saturated fats come in several forms. What is offered in red meat is different from that in coconut meat. And each may have different health impacts.
It has been found that replacing heavily refined carbohydrates with some saturated fat can improve conditions like insulin resistance, and fares far better for all-cause mortality than trans-fats.4
It is important to consider that while trans-fats and saturated fats are both structured similarly and therefore solid at room temperature, they can’t be considered the same when correlating health effects. The hydrogenation process of vegetable oils is designed to make them structurally similar to a saturated fat, but the process may not fully complete the structural change to be exactly the same as a saturated fat. Kahn Academy has a video that explains the changes in chemical structure in more detail.
In addition, in assessing health effects, studies can lump saturated fat intake together with trans-fats, not treating each as isolated nutrients with different health impacts. And while better health outcomes are seen when replacing either saturated or trans-fats with polyunsaturated fats, the source and quality of polyunsaturated fat should also be considered (think margarine compared with a handful of sunflower seeds – they are not nutritionally equivalent, one being highly processed, the other a whole food packed with beneficial nutrients that operate synergistically).
Perhaps the important thing to consider is the quality of the food containing the saturated fat. Choose ethically raised, pasture-fed, free-range or organic meat and poultry and first cold-pressed extra virgin coconut oil, as opposed to the heavily processed foods that include saturated fat. Enjoy it in moderation as part of a balanced diet, and alongside lots of other whole foods like vegetables.
Just eat real food
Fats needn’t be the antithesis of looking after one’s health. But the type of fat matters.
Keep consumption of trans-fats on the down-low by choosing olive oil, butter, or coconut oil, limiting heavily processed and deep-fried foods, and checking the labels for hydrogenated or partially hydrogenated vegetable oils.
By subbing out the heavily processed packaged stuff for real whole foods, we are deliciously on our way to good health!
By Angela Johnson (BSHc Nut. Med.)
- Gropper, SS & Smith, JL 2013, Advanced Nutrition and Human Metabolism, 6th, Wadsworth, Cengage Learning, Belmont CA
- Kummerow, FA, Zhou, Q, Mahfouz, MM, Smiricky, MR, Grieshop, CM, & Schaeffer, DJ 2004, ‘Trans fatty acids in hydrogenated fat inhibited the synthesis of the polyunsaturated fatty acids in the phospholipid of arterial cells’, Life Sciences, vol. 74, pp. 2707-2723.
- Baer, DJ, Judd, JT, Clevidence, BA, & Tracy, RP 2004, ‘Dietary fatty acids affect plasma markers of inflammation in healthy men fed controlled diets: a randomized crossover study’, The American Journal Of Clinical Nutrition, vol. 79, no. 6, pp. 969-973.
- de Souza, RJ Mente, A Maroleanu, A Cozma, AI Ha, V Kishibe, T et al., 2015, ‘Intake of saturated and trans unsaturated fatty acids and risk of all cause mortality, cardiovascular disease, and type 2 diabetes: systematic review and meta-analysis of observational studies’, British Medical Journal, no. 351, h3978.
- Han, SN, Leka, LS, Lichtenstein, AH, Ausman, LM, Schaefer, EJ, & Meydani, SN 2002, ‘Effect of hydrogenated and saturated, relative to polyunsaturated, fat on immune and inflammatory responses of adults with moderate hypercholesterolemia’, Journal Of Lipid Research, vol. 43, no. 3, pp. 445-452.
- Mozaffarian, D, Pischon, T, Hankinson, SE, Rifai, N, Joshipura, K, Willett, WC, & Rimm, EB 2004, ‘Dietary intake of trans fatty acids and systemic inflammation in women’, The American Journal Of Clinical Nutrition, vol. 79, no. 4, pp. 606-612.
- University of Maryland Medical Centre 2015, Omega-3 Fatty Acids, viewed 22 November 2016, <http://umm.edu/health/medical/altmed/supplement/omega3-fatty-acids>.
- University of Maryland Medical Centre 2015, Omega-6 Fatty Acids, viewed 22 November 2016, <http://umm.edu/health/medical/altmed/supplement/omega6-fatty-acids>
- Simopoulos, AP, & DiNicolantonio, JJ 2016, ‘The importance of a balanced ω-6 to ω-3 ratio in the prevention and management of obesity’, Open Heart, vol. 3, no. 2, p. e000385.
- Schwingshackl, L, Christoph, M, & Hoffmann, G 2015, ‘Effects of Olive Oil on Markers of Inflammation and Endothelial Function-A Systematic Review and Meta-Analysis’, Nutrients, vol. 7, no. 9, pp. 7651-7675.