A Complete, Academic Breakdown of Fat
What is fat?
The term fat is an umbrella term. It is uniquely something you consume, carry around within your body, and, unfortunately, may be labeled as if you are overweight. When we talk about what fat really is; however, all of these definitions amount to the same core component – Lipids.
Lipids are organic compounds comprised of "fatty acids" (the singular components of fat) that are insoluble in water. It is both the arrangement and type of these fatty acids dictating the variation of dietary fat and their effects within the body.
A fatty acid consists of a straight chain of an even number of carbon atoms, with hydrogen atoms along the length and one end of the chain and a 'carboxyl group' (a group of atoms found in organic compounds).
On Polyunsaturated fats
PUFA's are fats that contain Omega-3 and 6, with Omega-3s promoting numerous benefits for athletes. These fats are essential as we cannot create them ourselves; 'Omega' referring to the tail-end of the molecular chain, with the number denoting the position of the final bond in the chain.
There are numerous recovery and immune system benefits to getting your daily Omega-3's in, all of which are underpinned by Omega-3's global anti-inflammatory effects.
One well-documented benefit is the effect on the cardiovascular system. Wherein both aerobic and anaerobic athletics consumed adequate Omega-3 intake, this resulted in significantly enhanced cardiovascular function through enhancement of the endothelial cells (which form the lining of blood and lymph vessels) due to increased nitric oxide production.
Nitric oxide (NO) is an important regulatory molecule with a prominent role in vasodilation (the widening of blood vessels), enabling the body to take in more oxygen during exercise and also lowers blood pressure.
Further underscoring the benefits of Omega-3's on the cardiovascular system are the documented attenuation of bronchoconstriction; a tightening of the airways following exercise that is worst in athletes with asthma. This softens the effect of DOMS (delayed onset muscle soreness) and exercise-induced fatigue through promoting the release of anti-inflammatory cytokines (small proteins crucial in cell signaling) and suppressing the release of proinflammatory cytokines.
They also aid muscle recovery, specifically through a reduction in oxidative stress, (the imbalance between free radicals and antioxidants in the body) by decreasing F2 isoprostane (compounds that act as inflammatory mediators and are markers of oxidative stress).
In addition, evidence that adequate healthy fat aid in the regulation of the anabolic hormones and are instrumental in their function, having an obvious carryover to athletes and bodybuilders.
Aside from the above, a recent meta-analysis concluded Omega-3 consumption improves lipolysis (fat oxidation), but more evidence is needed.
Despite the plethora of benefits regarding Omega-3's, PUFA's are somewhat considered a double-edged sword, with the balance between 3 and 6 being highly important. It is estimated the average person consumes up to 20x more Omega-6 than 3! While Omega-6 fatty acids are essential to the bodily processes of clotting mechanisms and healthy immune function, too many can contribute to the reversal of this, as well as increase the risk of some cancers and cardiovascular disease.
It has even attributed to the early origins of obesity because the standard western diet skews the imbalance of the omega fatty acid ratios in gross favor of Omega-6. Current research suggests the most prominent factors are high amounts of vegetable oils (unbalanced omega-6's) and hydrogenated (trans) fats in the western diet, as well as excess refined carbohydrate consumption and along with deficiencies in key vitamins and minerals. Choosing to balance your cooking with these oils and saturated fats such as grass-fed butter and coconut oil can help alleviate this issue.
The Three Forms of Omega-3: EPA, DHA & ALA
Omega-3 is a collective term for several different types of essential fatty acids.
ALA (alpha-linolenic acid) is the most common and essential fatty acid (found mostly in plant-based foods), but the biologically available forms (the forms the body can readily absorb) are EPA (eicosapentaenoic acid) and DHA (docosahexaenoic). This means that ALA needs to be converted into DHA and EPA before it can be used.
Unfortunately, consuming ALA is not very bioavailable, meaning once digestion has taken place, you are not left with much DHA and EPA; with a conversion rate of less than 5-10% for EPA and 2-5% for DHA. This is why fish oils are popular, with their already high DHA and EPA contents forgoing the need for conversion. While fish oils are invariably your best choice for getting your Omega-3s in, however, not all are created equal. The World Health Organisation recommends a daily intake of 0.250 g/day of EPA plus DHA, so be sure to check your Omega-3 supplements or food serving for these amounts.
If you do not eat fish or follow a plant-based diet, although the conversion rate ALA is not the best, that does not mean ALA containing foods are not beneficial. Foods such as Chia seeds and walnuts can be incorporated into the diet for a decent, albeit weaker Omega-3 hit. And when there are lower DHA and EPA amounts in the diet, the body will increase its conversion rate of ALA to compensate. This results in research finding Omega-3 levels to be roughly the same between omnivorous and vegan and vegetarian diets.
The best plant-based source of Omega-3, however, comes from Marine Algae. Omega-3's are ultimately plant-based, existing in fish only due to their consumption of these high EPA and DHA containing algae and seaweed, available commercially as supplements in the same way that fish oil is. Again, as with fish oil, make sure you check these supplements for the adequate daily amounts of EPA and DHA.
Unlike 3 and 6, Omega-9 is considered conditionally essential in the body can produce it through adequate omega 3 and 6 balance, and so providing proper 3 and 6 balance is followed, its consumption is not of great concern. The main difference between Omega-9 and Omega-3 and 6 is their molecular make-up; the 'mono' referring to the fact that omega-9 fats only have one double bond, unlike the poly's, which have many. The benefits of Omega-9 are considered in tandem with those of Omega 6.
All nuts and most nut oils (olive oils, avocados, and seeds) are sources of monounsaturated fats.
Despite the bad press originating from the 1960's, beginning with Ancel Keyes's "Lipid Hypothesis," modern research suggests universally that saturated fats are not the leading cause of heart disease. A meta-analysis critiquing and discussing 27 papers found plasma lipid concentrations (dietary fat in the blood) was likely not related to increased CHD risk, with studies suggesting arterial plaque formed by predominantly unsaturated fat.
While no specific athletic benefits have been studied, there are benefits to a balanced, moderate consumption of saturated fats for the body, which carry over directly to athletic performance such as increased bone mineral density and enhanced immune system function, as well as being key in the utilization of the other essential fatty acids. Sourced include red meats, cheese, and coconut oil, to name a few.
Trans-fats are solid fats that have been 'man-made' through the process of catalyzation - heating vegetable oils with hydrogen to elicit carbon atoms bonding in a straight configuration. This process substantially increases food shelf life and aids mass production, allowing cakes and chips to maintain their solid structure at room temperature.
These fats have been universally condemned, and in many cases, banned or phased out in food production across the globe, with hundreds of studies documenting the dangers regarding CHD and all-cause mortality. In 1994, a study estimated that 30,000 premature CHD cases attributed to the consumption of these fatty acids!
Governing bodies are currently moving forward in attempts to ban trans-fats, and in the US, the FDA has taken steps to ban the use of these fats in processed foods.Trans-fat containing foods include fried fast food, processed baked goods, and margarine.
Practical Recommendations for the Athlete
Fat is easily trackable with fitness apps available on smartphone devices. Overall recommendations for fat will vary on an individual basis and will need to per relative needs. Based on the literature, a good rule for fat percentages for bodybuilders, strength & power, and endurance athletes is 20-30%, with a recommendation of 15-20% for athletes on caloric restriction.
With trans fatty acids to be minimized as much as possible, contemporary recommendations for saturated far are around 5-6% of the diet. This leaves the rest of your fat intake to come from the PUFAs and MUFAs.
The most prominent variable to consider is hitting your daily requirement for Omega-3, which across all major governing organizations, is around 250-500mg.
Omega-3 intake can also be achieved through supplements of fish or certain seaweed oil supplements. It's important to consider food quality as well. Cheaper, pre-cooked "lunch meats" tend to be higher in saturated fat and Omega-6's than that of grass-fed meats.
The exact ratio between Omega-3 and 6 is yet to be elucidated, so contemporary research recommends monitoring and limiting excessive consumption of high Omega-6 vegetable oils, and increasing use of oily fish and flaxseed to achieve your daily fat intake.Linden Garcia Pepworth is a Sports Nutritionist (BSc Sports Nutrition) and YMCA Accredited Instructor. He is currently working on a review comparing the anabolic differences between plant and animal proteins.