Source: http://whole9life.com/fish-oil-faq/

Here are some of the highlights, head over to their website for more information.
Q: Where do Omega-3 fatty acids come from?
A: Omega-3 fatty acids are found in the green leaves of plants, like grass, phytoplankton, algae and seaweed. This is the food that OUR food is designed to eat, which makes grass-fed beef, pastured organic eggs, and most importantly, certain types of fish (wild-caught fish and fish lower on the food chain, like herring, anchovy, sardine and mackerel) are good, natural sources of omega-3′s. Unfortunately, due to poor meat quality, and over-consumption of fast foods, processed foods, and vegetable oils, most of our diets are lacking in these essential fatty acids (and overly rich in pro-inflammatory omega-6 fatty acids).
Q: So why can’t I just eat grass or seaweed to get my omega-3′s?
A: First, you don’t have the ability to digest grass properly. Moving on, omega-3′s are a family of fatty acids, and the “parent” molecule is called alpha-linolenic acid (abbreviated as LNA or ALA). The ALA from plants is converted by animals or fish to the potent anti-inflammatory omega-3′s called EPA and DHA by a long conversion process (see the discussion of ALA from plant seeds below). The ALA itself is not actually anti-inflammatory, and only a small percentage of ALA can be converted to EPA and DHA. Fish (and to a much lesser degree, land animals) do the metabolic work to convert the plant-based ALA into concentrated EPA and DHA. Fish oil is already a concentrated source of EPA and DHA, which is why fish oil has such potent anti-inflammatory properties.
Q: Why can’t I get my omega-3′s from flax?
A: There are countless problems with getting your omega-3′s from this particular plant source. It requires an extremely inefficient conversion process – meaning your body has to do a lot of work to get the EPA and DHA you want out of the kind of fat found in flax (ALA). And the conversion pathway is fraught with difficulties that can, in fact, lead to MORE inflammation – the exact opposite of the intention. Finally, even if everything works perfectly, the amount of EPA and DHA you can actually convert from flax is so small it practically doesn’t count. (By the way, the story is the same whether you’re talking about flax, chia, hemp or echium.) Just stick with your fish oil.
Q: Why do I need EPA and DHA?
A: You only need a quick web search for this one, because there is a wealth of information on this subject. Fish oil is not a magic bullet, but there are an infinite number of well-documented benefits for a whole host of lifestyle diseases and conditions. The short answer is that EPA and DHA are specific types of polyunsatured omega-3 fatty acids. Your body cannot produce these fatty acids – you must get them from the food you eat, or via supplementation. EPA and DHA are natural anti-inflammatory agents, and as such, play a role in brain health, heart health, protection against cancer, Alzheimer’s and depression, improvement of skin conditions like psoriasis and acne, fetal brain development, inflammatory bowel disorders, and arthritis, to name a few.
Our typical diets are rich in another type of pro-inflammatory polyunsaturated fatty acid called omega-6. When our dietary intake of omega-6′s far exceeds our intake of omega-3′s, our bodies experience a wide range of negative consequences, all with the underlying cause of increased systemic inflammation. Minimizing dietary intake of omega-6 fatty acids, and supplementing your intake of omega-3 fatty acids, helps to reduce inflammation, and the wide range of downstream effects.
Q: Is there an ideal EPA to DHA ratio?
A: This isn’t particularly important – but a supplement in the general neighborhood of 1:1 would be a good find. DHA converts to EPA easier than vice versa, so if you had to choose, choose a high-DHA oil.
Q: What else should I look for in a fish oil brand?
A: First and most importantly, squeaky clean ingredients. This means your fish oil should be free of soy (including lecithin), dairy, wheat, rice, sweeteners or other artificial ingredients. (Visit our Supplement Evaluation Checklist for more information.)
Then, look at the EPA and DHA amounts per serving – that’s far more important than the “total fish oil” amount. A concentrated source means you have to take fewer pills or teaspoons a day – it’s more efficient, and makes it more likely that you’ll actually take your recommended dose each day.
Q: Are there any contraindications for taking fish oil?
A: Because fish oil capsules have an effect on reducing the stickiness of platelets, it is recommended that if you have any of the following conditions, that you see your physician to discuss whether you should take fish oil capsules:
-You have a bleeding tendency
-You are on blood thinning medications
-You are about to have surgery
Of course, before starting any new medication or supplement, it is always a smart idea to consult your physician, right?
Q: I’m pregnant – is it safe to take fish oil?
A: First, consult your doctor before starting any medications or supplementation. The general consensus is that EPA, and especially DHA, provide excellent benefits for your baby’s neurological and early visual development, and may reduce the risk of pregnancy complications like pre-eclampsia, gestational diabetes, post-partum depression and pre-term delivery. Your recommended dose will be different, however… again, check with your doctor to find a range that’s healthy for you and your baby.
Q: How much fish oil should I take?
A: Our general recommendations are to aim for around 2-4 grams of EPA/DHA per day. However, if you eat lots of wild-caught salmon, grass-fed beef and other natural sources of omega-3 fatty acids, and generally avoid sources of omega-6 (like vegetable oils, factory-farmed meat, nuts and seeds), you may not need any fish oil supplementation at all.
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