Nutritional Supplements #3: EFAs - Essential Fatty Acids.
By: Alicia Berthiaume (2004/04/28)
Canadian skiers are still buzzing about Beckie Scott's bittersweet Olympic medal, and as a result, we are gaining hope for a drug-free world of sport. But the debate about the ethics of supplementing (with vitamins, minerals or other) is still a foggy area for athletes. Without a little bit of understanding of the biochemistry behind the supplements, we put ourselves at risk on many levels. We may be taking something that is damaging to our health, we may be taking something in the wrong doses or we may be taking something illegal in competitive sport. It barely sounds worth it right? Don't be discouraged thought, there are many incredible benefits to supplementing, if you know what to look for. So over the next season XC Ottawa will feature a panel of vitamin, minerals, herbal supplement and others that have been in the limelight recently. Hopefully with a bit of explanation, we'll be able to understand what all the excitement is about! [Please check with your Doctor before starting use of any new supplement, 'natural' or otherwise]
As the first flowers spring up from the ground and we skiers wind down from another grueling season, it's time to turn our focus to rest, recovery, and review. The end of the season is the perfect time to begin repairing not only our equipment but also our bodies, after the wear and tear of the winter. An important part of this rejuvenation comes from good nutrition, and today's nutritional update on Essential Fatty Acids (EFA) will help explain how eating fat can be linked to being fit.
Let's start with the definition of Essential Fatty Acids. First, fatty acids are not normally present in our diets in their free form (free fatty acids), rather, they are components of fat, oil and cell membranes in the regular food of our diets. Once ingested, our bodies breakdown the fat/oil through digestion and circulation and from there the free fatty acids are liberated and assimilated into the body. Second, the term "essential" is used to distinguish the physiologically significant fatty acids which our bodies are NOT capable of synthesizing. Many of the fatty acids required by our bodies can be synthesized by enzymes in the liver, however some fatty acids are solely obtained through diet and are therefore deemed 'essential' and should be included in our daily food consumption.
So, what are fatty acids for? Well, fatty acids are not only used as a source of energy for our cells, they also play a major role in all biological membranes (every cell!), in nerve tissue integrity (insulation and conduction) and they are also critical precursors for many hormones, neurotransmitters and cell-regulators. So fats aren't just a source of mega-calories, some are also major contributors to many normal biochemical pathways.
Omega-3, and (some) omega-6 are groups of fatty acids that are gaining popularity as good fats and are 'essential'. Some examples of foods containing these types of fats are fatty fish (salmon, mackerel), flax seed, flax seed oil, hemp oil, walnut oil, borage oil, primrose oils and some dark leafy vegetables. The oils are not only available as pressed oils; they are also available in capsule form.
The area I want to focus on is the influence of EFAs on inflammation. Because inflammation is a common problem for athletes, we tend to reach for ibuprofen fairly often, and although it works well, it can be hard on the stomach. Alternative treatments and nutritional options are important to know about. So, what is happening when inflammation occurs, and what will EFAs do?
Well, inflammation starts when a distress signal is sent out by a damaged cell or by an immune cell. Other cells in the general vicinity detect the distress signal through special receptors on their membranes, and a specific enzyme in the cells is subsequently activated. The action of this enzyme (Phospholipase A2) is to cleave fatty acids from the cell membrane.
Now, which fatty acids are cleaved depends on the relative abundance of each within the membrane of the cell, and that is directly dependent on what types (and abundance) of fatty acids we are eating.
After fatty acids are cleaved, they go on to be converted into different types of chemical messengers, called eicosanoids. Different fatty acids produce (through reaction with an enzyme) different eicosanoids leading to different messages and cellular responses. So, in essence, the message that is sent out to the cell is dependant on what types of fatty acids we eat.
Ok, so what types of messages can be sent out to the cell? Well, among many others, some EFAs send pro-inflammatory messages (Arachidonic acid, AA) and others send anti-inflammatory messages (Alpha-linolenic, ALA; Eicosapentaenoic acid, EPA; Dihomogammalinolenic acid, DGLA; Gamma-linolenic, GLA). Interestingly, even though different EFAs produce different eicosanoids (messages), with opposing effects, it is the same enzyme that is used by both reactions. So, there is an overall competition by the EFAs for the enzyme, and the effects of the competing EFAs are antagonistic.
The key to good health here is to achieve a balance of different types of fatty acids, so that no single response (neither pro- nor anti-inflammatory) can always dominate. With the North American diet containing as much corn oil and corn products (pro-inflammatory fatty acids!!) as it does, this may be harder than you think. Now, this doesn't mean that corn is bad (it also contains some essential fatty acids!), it just means that there is a seriously abundant supply of it available to us, making imbalance easy, and our susceptibility to inflammation high. A further obstacle in EFA balance is the popularity of low-fat eating habits among athletes, which can lead to deficiency in EFAs. So, how do we get the right balance of the right fats?
The most logical way to achieve a healthy equilibrium and to moderate pro-inflammatory messages is to include more good fat in your diet, and to monitor the not-so-good fat in your diet. Adding fish, soybean and flax seed etc. to your everyday diet is a good way to do this, and/or you can take an EFA supplement. Avoiding stuffing yourself with Corn Pops is another way. Usually the supplements are a combination of several oils (commonly salmon, borage and flax oils), easily giving you a balanced dose of different "good" fatty acids in one capsule. EFA supplements are generally well tolerated and should be taken in combination with a regular multivitamin or other antioxidant source. Importantly, stinky burps from capsules can be avoided if the supplement is taken with a meal!
Reduction of inflammation is just one of the many benefits of balanced EFA consumption. There are too many to list, but as a quick secondary point of interest about EFAs, I wanted to mention their link to asthma as well. Asthma is a fairly common problem among athletes, whether it's exercise-induced or otherwise. The chemical that causes the bronchoconstriction associated with asthma is derived from the same pro-inflammatory fatty acids we just discussed (AA). The rationale for reducing inflammation by increasing the abundance of anti-inflammatory fatty acids is the same rationale for reducing the severity of asthma with good EFA balance. If you can skew the competition for the enzyme by having more good fatty acids available, AA has less opportunity to bind to the enzyme, therefore less opportunity to send bronchoconstrictive messages out.
So the next time your knee is sore or your wheeze makes a comeback, or you just want soft hair, try a drug-free way and reach for the EFA!