Q. About 10 years ago I cleaned up my diet big time. I was eating so many fresh fruits and vegetables I figured I no longer needed the multi-vitamin and fish oil I had been taking. After about a year I was feeling great physically, but could not concentrate as well as I used to. I read the term “brain fog” and thought that was definitely what I had.

I started taking fish oil again, just a 1,000 mg capsule daily. Within about a month or so my mind felt noticeably more clear and agile. I’ll never stop taking fish oil as long as I can get it.

A. The benefits of fish oil are controversial when it comes to cognitive function. A review of the literature points out that animal studies are consistently positive and that fish oil supplements seem to help with mild cognitive impairment–what you are calling brain fog–but not Alzheimer’s disease (Advances in Nutrition, Nov, 2013).

A large, long-term study of women found that those with the highest levels of omega-3 fatty acids in their red blood cells had less brain shrinkage (atrophy) on MRI testing (Neurology, Feb. 4, 2014). Most nutrition experts recommend eating fatty fish at least twice a week to get adequate levels of fish oil.

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  1. Jerry
    New Jersey

    I’d been taking fish oil consistently for quite some time and over the past few months have been developing worsening brain fog until it was getting to intolerable levels over the past few days. The day before yesterday I decided to see if my discontinuing fish oil would have any effect and for the first time in several months I feel much sharper mentally with increase clarity, memory, mood, mental stamina, and cognition. So for me at least, it was having a paradoxical effect.

  2. DS

    Please keep me posted on this topic.

  3. Cindy M. B.

    Some reputable websites are now absolutely DECRYIING the use of fish oil, saying that it doesn’t just fail to provide the touted benefits but in fact it can “hasten aging and debilities of all kinds.” This was a shock when I first read it, and I set about finding out WHY they would say such a thing. Well, it turns out that it’s all because (as they claim), the fish oil can get rancid and that’s how it can hurt you. So, it’s not the fish oil itself but possible rancidity that can cause problems.
    Well, I switched to krill oil, and I always keep it in the fridge! But I see fish oil all the time on store shelves, unrefrigerated, and they don’t say to refrigerate the product once opened, either. Can the threat of rancidity (and attendant health problems) be all that valid? I’d love to hear what PP might have to say about this. Thank you.
    People’s Pharmacy response: It is important not to take rancid oil of any kind. If you hang onto your fish oil long enough for it to go rancid, keep it in the freezer. That won’t harm it. The same goes for flaxseed or borage oil, or any other oil taken as a supplement. If it smells bad, toss it.

  4. Liz H

    My CFS doctor showed me a published study showing that Omega3 repairs brain tissue. It’s been a wonder drug for me.

  5. Barb

    I found a good 1360mg fish oil that contains 950mg. active Omega 3. It contains 625 mg of EPA and 244 mg. of DHA. I also eat 1/4 cup of walnuts and almonds every day with my high fiber green, orange and red salad and a sandwich of 2 slices of spelt bread made with either cucumber or tomato on alternate days. In between days are boiled egg white or tuna salad. I use organic romaine lettuce when I can find it and organic carrots. I eat about half a tomato every day in one form or another. I’m an 82-year-old woman weighing about 112lbs. I walk forty minutes a day and work out 3 days a week. I also play scrabble every week to keep cobwebs at bay (and to have fun!)

  6. alxzba

    interested in receiving future comments on this. thanks.

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