Notes from DrKF:
Look for an algae-based omega-3 supplement that contains both DHA and EPA. Interestingly, it’s all the algae that fish eat that makes fish such a good source of omega 3s; these supplements help you go straight to the source. And make sure you’re eating plenty of plants that are rich in the omega-3 fatty acid alpha-linolenic acid (ALA), including flax seeds, chia seeds, walnuts, and hemp seeds. Your body has to convert ALA into the most important forms of omega 3s—EPA and DHA—and the conversion process is very inefficient for most of us. So it’s helpful to eat a lot of ALA and take an algae supplement.
Dosage for ALA: Shoot for about 3 to 5 grams of ALA per day, but I recommend using the whole food to get it. For ground flax seed (my top ALA source), that would be one to two tablespoons per day.
Dosage for EPA and DHA: Try to get at least 300 mg combined EPA and DHA daily, and possibly more if you are older, pregnant, or nursing, or if you have an inflammatory condition such as heart disease, autoimmunity, or allergies. (Testing your levels of EPA, DHA and ALA is particularly useful.)