As a Foodpunk you probably already know that when it comes to fat, the point is not to cut back but above all to choose quality. And you will certainly have heard that there are omega 3 fatty acids with many useful properties. They can boost fat burning and lower raised blood fats (triglycerides), for example, and in that way help protect against cardiovascular disease. In another article we have already gathered all the important information about omega 3 fatty acids for you.
What matters most here are the highly unsaturated omega 3 fatty acids EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). They occur abundantly in fish, seafood and certain algae, and in smaller amounts in the meat, eggs and milk of pasture raised and wild animals. EPA and DHA are important parts of cell membranes and help determine their firmness and flexibility. That matters, because it also decides how well a cell can take up nutrients and move its “goods” (enzymes or hormones, for example) or its waste out again. You may have heard or read all of this before. But have you ever thought about your immune system in connection with omega 3 fatty acids? There are some fascinating findings there, and I would like to give you a short introduction.
Out of highly unsaturated fatty acids the body also builds a whole range of signalling substances. These “messengers” can promote, prevent or end inflammation, among other things. While most, though not all, highly unsaturated fatty acids from the omega 6 family are turned into inflammation promoting signals, highly unsaturated omega 3 fatty acids mostly become anti-inflammatory or inflammation resolving “messengers”. When these processes are in balance, the immune system benefits too. During a viral infection, for example, it first needs inflammation promoting signalling substances. After that it needs the anti-inflammatory or inflammation ending messengers. So this is not about having as much as possible of one kind or the other, it is about balance. And that balance is missing on many plates, where there are often too many omega 6 and too few omega 3 fatty acids.
If we eat enough long chain omega 3 fatty acids, they accumulate in the cell membranes of our immune cells as well. That also changes the “messengers” (cytokines) the immune cells send out. Until now it was assumed that these “messengers” weaken or end inflammatory responses. Is that good or bad for our defences? More recent studies have looked into this question and investigated how omega 3 fatty acids affect the various cells of the immune system. In short: differently. And that is a good thing.
It turned out that some immune cells are activated by omega 3 fatty acids while others are inhibited. The fatty acids therefore act in a balancing and regulating way on the immune system, not in one direction only. In doing so they help protect against diseases of civilisation (type 2 diabetes or heart attack, for example) and against excessive immune responses (allergies, autoimmune diseases), which are marked by too much inflammation. At the same time they support immune cells in their work and increase their effectiveness. Particularly fascinating and new: omega 3 fatty acids work together with immune cells and the gut flora to keep the gut wall intact and tight. In that way they help prevent a “leaky gut” and contribute to a fit immune system along this route as well.
The immune suppressing (and blood thinning) effects of highly unsaturated omega 3 fatty acids only become critical from around five grams a day. With a usual diet, and with a fat rich ketogenic diet as well, such amounts are generally not reached. Anyone who wants to take omega 3 fatty acids in high doses should definitely speak with a doctor or nutrition therapist beforehand and have their status measured in the blood. The so called omega 3 index is ideal for that, showing how high the proportion of DHA and EPA is in the membranes of the red blood cells. From that you can tell whether additional supplementation is necessary or sensible. Anyone who eats fish and seafood regularly may well be sufficiently supplied with these important immune modulators, and with other important nutrients for the immune system such as protein, selenium, iodine and zinc. With fish and seafood, please do pay attention to sustainable sources, or switch to algae, algae oils or residue tested fish oils.
Gutierrez, S et al.: Effects of omega-3 fatty acids on immune cells. Int J Molecular Sci 2019;20:5028, doi: 10.3390/ijms20205028
Parolini, C: Effects of fish n-3 PUFAs on intestinal microbiota and immune system. Marine Drugs 2019;17:374, doi: 10.3390/md17060374
