The result of our immune system wrongly attacking our body cells is inflammation. Inflammation in our lungs leads to difficulty breathing. Inflammation in our joints and muscles causes pain. And inflammation in our gastrointestinal tract causes a variety of different complications such as diarrhea or constipation, blood in the stool, abdominal discomfort and more.
Fish oil possesses powerful anti-inflammatory properties. Once this was understood scientists began studying the effect of fish oil supplementation in a wide variety of autoimmune diseases.
The term “autoimmune” is used to encompass a long list of diseases. Autoimmune implies that our immune system begins to wrongly attach cells of our own body, or otherwise overreacts to normal environmental triggers. In essence, almost all diseases characterized by long- term inflammation fall under the umbrella term “autoimmune”. A very limited list of conditions include; arthritis, inflammatory bowel disease (Crohn’s disease, Ulcerative colitis), asthma, eczema, chronic fatigue syndrome, fibromyalgia, psoriasis, etc… Although each condition listed above possesses very unique characteristics, the underlying problem associated with all of them is inflammation.
How EPA and DHA can reduce inflammation
The main ingredients in fish oil are EPA and DHA. When EPA or DHA take the place of arachidonic acid (AA) the result is inhibition of inflammatory processes. The target of pain killing medications is to prevent the action of the enzymes which make cytokines. EPA and DHA use a completely different target. They do not block the enzymes which make the cytokines, instead they replace the fat the cytokines are made from.
Both EPA and DHA compete with AA for conversion to cytokines
Supplementing with fish oil leads to a very substantial increase in the amount of EPA and DHA in cell membranes. When phospholipase A2 searches for a fat it now has a much greater chance of releasing a molecule of EPA or DHA instead of releasing a molecule of AA. With less AA released from the membrane, less cytokines formed from AA will also be produced. The net result is a reduction in inflammation. This is the “competitive effect” of both EPA and DHA on cytokine production.
EPA produces anti-inflammatory cytokines
When cyclooxygenase or lipoxygenase act upon EPA new cytokines are made. The cytokines produced from EPA are similar in structure to the cytokines produced from AA but they have very different biological effects. Instead of promoting inflammation and pain, the EPA- derived cytokines are anti-inflammatory. They will oppose the action of cytokines which do end up being made from AA.
Due to the concept of competition with AA, DHA is able to benefit inflammation. DHA does not give rise to biologically active cytokines. This suggests that EPA is likely more important to the prevention of inflammation than DHA, although both EPA and DHA have shown benefit to inflammation in human studies.