And I’m done exams, wohoo!! No more classes until January 7th ! I really want to focus on my blog this Christmas break; I’ve got a few topics in mind before I start researching the suggested topics from some of you guys. If any of you have any requests, feel free to ask and I’ll make a list and eventually get to it .
My roommate and I had our Christmas party last night, couldn’t have asked for a better group of people who came; it was a really nice reward after all of our exams . After spending most of the day climbing (obviously), we came home and decorated the house with Christmas lights, homemade snowflakes and a cardboard Christmas tree I taped to the wall . I definitely feel the holiday spirit now, ready to get onto some vegan holiday creations!
Here’s a picture taken of me in Kentucky from some of my American friends- Thanks Matt for the picture …
There’s a lot of confusion about the effects of omega 3 and omega 6 polyunsaturated fatty acids, so this post will be an attempt to make sense of it all for you guys. Hope you enjoy !
So first things first, what are polyunsaturated fatty acids? Polyunsaturated fatty acids (PUFAs) are just what their name describes, fatty acids that are unsaturated with multiple double bonds; the location and number of double bonds play a role in determining their properties. PUFAs are essential in mammal diets because we lack enzymes to put a double bond in either the 6th or 3rd position of fatty acids and therefore cant create them endogenously. Both omega 3s and omega 6s play an important role in altering cell membranes, signalling molecules, gene expressions, etc.
Omega 6s are abundant in modern diets, especially in corn and soy bean oils and grain-fed meat. Omega 3s on the other hand are less available, they should be actively incorporated into our diets. Omega 3s are found in only a few foods, primarily in fatty fish (increasing at decreased environmental temperatures for the fish in order to maintain membrane fluidity) and certain vegetables and nuts. Algae and phytoplankton make omega 3 which is eaten by fish, omega 3 increases up the food chain through bio-accumulation. Nut omega 3 typically comes in an alpha linolenic acid (ALA) form whereas fish typically has docosahexaenoic acid (DHA), but I’ll get to that later…
From an evolutionary perspective, we evolved on a diet with a PUFA ratio of omega 3s:6s at about 1:1. Today that ratio has shifted to over 15:1 commonly. The ratio of PUFAs are important for regulating homeostasis and growth.
Omega 3 has a counteracting action to omega 6; while omega 6s promote coagulation, angiogenesis and inflammation for example, omega 3s are anticoagulants, anti-angiogenic and anti-inflammatory. Omega 3 has been shown to have anti-tumor properties and a role in the protection against many chronic diseases including heart disease. In contrast, omega 6 was shown to promote tumor formation and growth as well as promote heart disease. Both are essential and required for optimal health (for example, in the case of clotting; the pro-coagulating and pro-inflammatory properties of omega 6 are very important).
Omega 3s and 6s compete for cell membrane incorporation; higher levels of omega 3s in our diets can help prevent adverse effects associated with omega 6s. Again, many chronic diseases, e.g. heart disease, cancer, diabetes, rheumatoid arthritis, depression, asthma, etc, are associated with an increased omega 6 intake. Risks can be effectively reduced by increasing your omega 3 intake. Since many chronic diseases start in utero, proper PUFA consumption is important in pregnancy (and before) (also important for normal brain development).
The primary omega 6 is linoleic acid (LA) which is converted to arachidonic acid (AA). The three primary omega 3s are alpha-linoleic acid (ALA) (the form in many vegan omega 3s), docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA); ALA can be converted to EPA and DHA following consumption. This conversion is quite inefficient; consuming preformed EPA and DHA may be necessary to meet dietary requirements for omega 3. There are, however vegan DHA supplements out there derived from algae (but typically at lower concentrations than fish oil supplements).
So I’ll end things here, hopefully I got the point across for the need to up your omega 3 intake! Hope you all have an awesome weekend!
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