In my latest post I briefly discuss the importance of omega-3 fatty acids for nearly every function in our body! From fetal and early childhood development to memory retention, visual acuity, heart health, and cancer prevention these long-chain essential fatty acids are critical at all stages in our life! Sadly, around 4.5% of Canadians get enough of this important nutrient.
Like many others, my own mental health has become of utmost importance during this pandemic. While I'm generally a pretty outgoing and extroverted person, I've been finding that lately, my energy levels have been in a bit of a funk lately. So naturally, as a Registered Dietitian, I spent the weekend refreshing my knowledge on the importance of nutrition and mental health. I have to say, the liver will always be my favourite organ but the brain is a close second. Here's what I found.
Weighing in at roughly 2 pounds, it is one of the most complex organs we own playing a role in everything from speech, memory, movement, emotions. It is also one of the fattiest organs in the body, nearly 2/3 are made up of essential fatty acids! Who knew. Essential fatty acids are required for optimal health, however, similar to how your body needs essential amino acids from the diet to grow and repair muscle fibres (think leucine and tryptophan), your body requires EFA’s from the diet as well. Sadly, many of us living in North America are deficient in it which poses future health care risks.
There are two main types of essential fatty acids that we need to get from the diet: 1) omega-3 (alpha-linolenic acid) and 2) omega-6 (linoleic) both of these are “polyunsaturated” in nature since they have more than double bonds at the end of their backbone. In contrast, monounsaturated fatty acids (MUFA's like olive oil and avocado) only have one double bond. For the purpose of this article, I will mainly be discussing the former since omega-6's or Linoleic acid are prominent in the western diet (corn and vegetable oils). Unfortunately, an abundance of processed foods in the food supply has shifted our diets in favour of these "pro-inflammatory" fats resulting in a decrease in omega-3's and an increase in hypertension.
Both kinds of PUFA’s have an important role in maintaining the integrity of our cell membranes, and provide our bodies with energy to function! Omega-3’s have been shown to play a key role in chronic diseases like cancer, insulin resistance, ADHD, and cardiovascular disease at all stages of the life cycle.
Did you know that Greenland Eskimos who consume large amounts of fat from seafood have a lower prevalence of heart disease? It’s not surprising given that fish is rich in omega-3 which we know can help with high blood pressure, triglycerides, and narrowing of our arteries.
There are a few types of omega-3 fatty acids, EPA, DHA, DPA, ALA. ALA is common in plants and seeds like hemp hearts, chia seeds, flax seeds, however as a shorter-chain FA it is not as biologically active in the body as the other two. In fact, research suggests that the conversion to EPA and DHA in the mitochondria can be as low as 5-10%! From a dietary standpoint, this is important because in order to produce these Eicosanoids we need to know whether or not we can obtain EPA and DHA from plant-sources or not.
In general, EPA and DHA from fish sources have been researched a lot more than the plant-derived ALA source. For example, DHA, in particular, helps to modulate the electrical signalling that happens within the cell in the body which helps us to learn new things, retain information and see things in detail. Higher levels of DHA are also important during the third trimester of pregnancy and the early stages of a child’s life.
Likewise, EPA is associated with anti-inflammatory properties which help to play a role in CVD and mood disorders like depression. In a 2009 study looking at whether or not Omega-3 fatty acid supplements improved the cardiovascular risk profile of subjects with metabolic syndrome, 89 patients treated with EPA+DHA had a significant reduction in inflammatory markers like CRP and were had a better return of blood flow to the heart following a period of tissue damage. Similar trials like the REDUCE-IT intervention, also found that 4 grams of EPA had a 25% risk reduction of dying from heart disease or suffering from a CVD event in over 8,000 middle-aged older adults.
While there are no established amounts by the IOM for EPA and DHA, 1.6 g/ day for F and 1.1 g/day for males is recommended for ALA. However, to reap the benefits of the former the general consensus would be to have two 3-ounce servings of fatty fish per week and incorporate foods rich in ALA as well like flax, chia, omega-3 eggs, canola oil. Some excellent choices of EPA and DHA rich foods include salmon, trout, mackerel, sardines, tuna. Doug Cook, RD, MPH has an excellent nutrition breakdown of fish sources on this blog post. If you are vegetarian or vegan an algae-based supplement like AquaOmega is an option. In fact, fish can’t actually synthesize omega-3 themselves they reap the benefits through things like plankton or algae. Supplementation is also a feasible option just make sure you speak to your healthcare professional to make sure none of your medications negatively interact (ie, Warfarin).
This post is merely scratching the surface of some of the benefits of omega-3 fatty acids, but there have been a lot of double-blind randomized control trials and observational studies (think VITAL, REDUCE-IT) that have looked at high levels of EPA and DHA for cancer prevention, memory delay, rheumatoid arthritis, depression, heart disease.
Hope you enjoyed this article, omega-3 FA's are only one of many important nutrients needed for brain health (Vitamin D, K2, Mg) are a few other important ones.
Yours in Health,
