Dietary fats 101
Dietary fats are one of the three main macronutrients and they have a wealth of roles and benefits for our bodies and performance. Dietary fats are essential for energy production, cell function, temperature regulation, organ protection, nutrient absorption and hormone production. It would be fair to say, dietary fats are important.
What about the different types? Well, you’ve got the ‘good’ sources in mono- and poly-unsaturated fats, the latter being home to the omega-3 and omega-6 fatty acids. Omega-3 and omega-6 have numerous roles within the body. Omega-3 can be found as EHA and DHA as well as ALA (plant sourced). For EPA and DHA, the best sources are oily fish such as mackerel, trout, tuna and sea bass but salmon typically tops the charts for omega-3. When it comes to ALA, chia seeds and flax seeds rule the roost with soybean and canola oils not far behind. Unfortunately, whilst ALA is the most common it’s also the most inefficient form of omega-3 and requires conversion to EPA and DHA in our bodies but only 1-10% is actually converted.
Omega-3 acts as a starting point for many hormones and has a role in blood clotting and arterial contraction while omega-6 aids skin and hair growth, maintain bone health and metabolism plus many others. From a sports perspective, it’s easiest to think of them as anti-inflammatory (omega-3) and pro-inflammatory (omega-6). On the other hand, you’ve got the ‘bad’ sources in saturated and trans fats. You would be hard-pressed to think of a time and place where trans fats have a beneficial role for our health and saturated fats play a role in energy production and organ protection, however, neither should be consumed in high quantities (<10% of total intake). Regardless of type, all fats contain the same amount of energy, 9kcal per gram, and while they pack more punch per gram than carbohydrates, they serve a very different purpose for energy usage.
Let’s track back to those polyunsaturated fats, the omega-3 and omega-6s. Again, the best way to think about them from a performance view is anti-inflammatory (omega-3) and pro-inflammatory (omega-6). While both are essential and should be consumed in a 1:2 ratio, if you’re in the midst of a training block and the goal is adaptation then you might want to be mindful of how much omega-3 you’re consuming. After you’ve banked a solid workout and entered the recovery phase, inflammation is key to training adaptations and a high intake of omega-3 may dampen the effects. This is not to say you should ramp up your pro-inflammatory omega-6s, you want to allow the inflammation to do its thing not drive it into overdrive.
When we exercise we will use a mix of carbohydrates and fats as our energy source, however, the contribution of each will vary depending on the intensity. Fats come into their own during lower intensities, if we’re talking about a scale of 1-10 it would be less than 6/10 with the maximal fat contribution at a 4/10 effort. This is not to say fats are used at high intensities, they merely occupy a smaller portion of the total energy used. If you are in a sprint or an intense team-based sport, such as the 100m or volleyball, you would be unlikely to utilise a large portion of dietary fats. If endurance events, such as marathon running or long-distance cycling, are your calling, fats are likely to have a larger role to play but they will remain second fiddle to carbohydrates.
