A WSJ article doesn’t reach much of an answer:
Hardly a month goes by without a study suggesting that the omega-3 fatty acids in fish oil can fend off disease — including heart attacks, strokes, Alzheimer’s disease, depression, rheumatoid arthritis, asthma, psoriasis and even attention-deficit hyperactivity disorder.
The problem is, to get the health benefits seen in clinical trials, you probably need to take fistfuls of capsules.
“The kind of benefits seen in most of the clinical trials with omega-3 generally have involved much higher doses than you see recommended on supplement labels,” says Charles Serhan, a Harvard Medical School expert on omega-3’s activity.
Which raises a little-discussed point. For practical purposes, it’s not enough to show that a drug works; you also need to find out the minimum dose that produces near-optimal results. In layman-speak, you need to find “the right dose.” Studies that compare drug and placebo are no help; much better would be studies that compare dosages (e.g., Group A gets one dose, Group B gets a different dose).
Here are three more useful comments:
1. I found that about 3 Tablespoons/day of flaxseed oil was enough to produce the best brain performance. As I’ve said, the amount that optimizes brain performance is likely to be a good amount for everything else. For the same reason that the best voltage pattern for your TV is likely to be a good voltage pattern for your other electrical appliances.
2. You can choose the minimum dose of fish oil that makes your gums perfectly pink. The transition from reddish gums (a sign of inflammation) to pink gums (no inflammation) takes about a week.
3. You can do mental tests to choose your dose, as I have done. The big problem here is practice effects — you will get better at the test just from doing it. So you will need several weeks of doing the test before the practice effects become small. You have to be a little bit sophisticated at data analysis — at least, able to plot your data — to take this approach.
In the future I can imagine people repeatedly measuring their mental ability with short (2-3 minute) tests, just as diabetics measure their blood sugar today.
Thanks to Santosh Anagol.