Omega-3 and omega-6 are two types of fatty acids. They participate in essential chemical reactions in your body and are deemed essential in humans. Since your body cannot produce these fatty acids, you must obtain them in your diet. Your body converts the omega fats into eicosanoids, a class of chemicals with functions ranging from blood pressure regulation to inflammation and pain signaling.
Omega-6s
The most common fatty acids in the Western diet are the omega-6s, according to "Kelley's Textbook of Rheumatology." Sources of omega-6s include vegetable oils such as canola oil, sunflower oil and corn oil, as well as nuts, grains and most seeds. The most common omega-6 is linoleic acid, which is essential to life because it helps form arachidonic acid. Your body derives a wide array of important chemicals from arachidonic acid, including prostaglandins and leukotrienes.
Omega-6 Pathway
When you eat omega-6 fatty acids, they are inserted into the membranes of your cells and stored. Many stimuli can cause your body to convert omega-6s into a compound known as arachidonic acid. These stimuli include stress and infection. Your body uses two enzymes to break down arachidonic acid. The enzyme 5-lipoxygenase converts arachidonic acid into leukotrienes and prostaglandins, which help your body fight infection. The second enzyme is called cyclooxygenase, which converts arachidonic acid into prostacylins and thromboxanes, which modulate pain. Medications including aspirin and ibuprofen inhibit cyclooxygenase and thereby reduce pain.
Omega-3s
One dietary source of omega-3s is in the form of ALA, or alpha-linolenic acid. ALA is found green leafy vegetables, nuts such as walnuts, in addition to flaxseeds and vegetable oils including soybean and canola oils. EPA and DHA are two other omega-3s. These are found primarily in fatty cold-water fish such as sardines, salmon and herring.
Omega-3 Pathway
The omega-3s found in fish are DHA and EPA. The same enzymes involved in omega-6 metabolism, lipoxygenase and cyclooxygenase, break down these fatty acids into compounds that help regulate blood clots, reduce risk of cardiac disease, and suppress abnormal heart rhythms, according to the textbook "Biochemistry."
Considerations
If you derive your omega-3s as ALA from plant-based sources such as flaxseeds or walnuts, additional reactions are needed to break it down. A key enzyme is delta-6 desaturase, whose activity is diminished with age and in some chronic diseases. Therefore, certain people may require supplementation with EPA and DHA, especially if you do not consume fish. For more information, talk to your doctor.
References
- "Kelley's Textbook of Rheumatology"; Gary S. Firestein, M.D.; 2008
- "Biochemistry"; Richard A. Harvey, Ph.D.; 2010
- "Pathologic Basis of Disease"; Vinay Kumar, M.D.; 2005
Member Comments