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Rapid Effects of Omega-3 Fats on Brain Function. Seth Roberts University of California, Berkeley. Outline. background choosing a dose 2 self-experiments other people, other effects conclusions. Chemical Background. omega-3 fats are polyunsaturated fats
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Rapid Effects of Omega-3 Fats on Brain Function Seth Roberts University of California, Berkeley
Outline • background • choosing a dose • 2 self-experiments • other people, other effects • conclusions
Chemical Background • omega-3 fats are polyunsaturated fats • Three versions vary in number of carbons: 18 (ALA), 20 (EPA), 22 (DHA) • ALA in plants. EPA & DHA in fish. Humans make EPA & DHA from ALA. • Flaxseed oil rich in ALA. • Brain 2/3rds fat (not counting water). DHA most abundant fat.
Health Effect? • 1972 Eskimos much less heart disease than Danes. Much more EPA & DHA in blood. • Now: Effect of fish oil on heart disease not entirely clear. • Now: Inconsistent effects on mood • Now: Several studies correlate fish consumption & better cognition in elderly • Now: Consistently improves ADHD
How I Got Involved • The Shangri-La Diet (SLD) showed how to drink olive oil & lose weight. • Many SLD dieters reported better sleep. • Due to omega-3? I took flaxseed oil capsules one evening. • Next morning my balance was better. • Could this be confirmed?
Measuring Balance • Slow learning, continues for a long time • One test/day, to keep learning constant • 30 trials/session – the most I could bear • Took about 15 minutes • Every morning. Before any flaxseed oil that day.
What Dose? Conclusions • 3 T/day flaxseed oil better than 2 T/day • 4 T/day about the same as 3 T/day • Dose effect inconsistent with placebo effect. (Initial effect also inconsistent.) • With other effects of omega-3 the best dose is unclear.
Expt 1: flaxseed oil vs olive oil • Took 4 T/day flaxseed oil most days (4 T flaxseed oil contains 28 g ALA) • For 9 days took 4 T/day olive oil instead
Expt 2: memory-scan measure • Each test: 5 blocks of 100 digits each. • Took about 4 minutes.
Expt 1: arithmetic measure • Simple arithmetic problems, randomly-chosen: • 5+3, 7-4, 7*8 • Answer (type answer, hit return) as quickly as possible. Measure of performance is reaction time. • 100 problems/session. Each session took about 2 minutes.
Expt 1: digit-span measure • Typical digit span task. See digits 1/sec in center of screen. 3 sec pause. Test: recall all digits in correct order. • Adaptive staircase: number of digits increases after correct answer, decreases after incorrect answer. • About 15 trials/session. Takes about 8 minutes.
Expt 2: flaxseed oil vs. nothing • Took 4 T/day flaxseed oil most of expt. • For 12 days, stopped taking flaxseed oil
Other People • Tim Lundeen, software developer, Bay Area. Simple arithmetic. • Sander Van de Cruz, graduate student, Copenhagen University. Iconic memory task. • My mom. Balance test.
Other Effects • Gums better (less inflammation) • Sports injuries better (less pain & swelling)
Dental Health • Me. Dentist noticed gums not inflamed. Never before like this. • Tyler Cowen, Marginal Revolution. Gum surgery cancelled. • Three other people.
Dental Health: Tyler Cowen • January 2007. Gum specialist: “You’ll need surgery either right now, or within a few months. We cut open the gum, clean out the inflammation, and sew your mouth right back up. Only sometimes do we have to eliminate the tooth.” • July 2007. Gum surgeon: “We can cancel this morning’s surgery, it seems OK for now.”
Sports Injuries • Starting taking flaxseed oil (2 T/day) because of Cowen story. Gums stopped bleeding. • “Full contact fighting leads to all kinds of sprains, strains, dislocations, etc. Ever since I started taking it --in caplets, equivalent of 2 tablespoons a day--I have noticed a big reduction in the number of small injuries, and a reduction in recovery time for those injuries.”
Sports Injuries (cont.) • “I used to have to take four Advil every day before I went to class because I was so sore from the previous days. Now I don't take any--and I haven't changed anything other than the flaxseed tablets.” • Stopped taking flaxseed oil. In about 10 days, soreness and bleeding gums returned.
Placebo Effect? • Placebos never show a dose effect. This does (2 vs 3 T/day). • Placebos never have unexpected effects. This does (dental & sports injury effects).
Conclusions: Substance • Flaxseed oil produces rapid improvement in cognitive functions and balance. Improvement disappears slowly. • Omega-3 the crucial ingredient • Best dose around 3 Tablespoons/day (= 350 calories). Health benefits clear with 2 T/day.
Conclusions: Method • Self-experimentation allowed fast, flexible study of accidental effect. Long ingestion better digestion. • Got source (flaxseed oil) & dose right. • Benefits much clearer than before. • Blogging caused others to try. • Methods of cognitive psychology can improve health. Optimize brain optimize body.