Genius Food

I’ve briefly mentioned another common omega-3: plantbased alpha-linolenic acid, or ALA, found in seeds and nuts

like flaxseeds, chia seeds, and walnuts. In our bodies, ALA

needs to be converted to DHA and EPA to be used, but this

is a very inefficient process, and what limited ability we

possess further declines with age.

26

Healthy young men convert an estimated 8 percent of

dietary ALA to EPA, and 0 to 4 percent to DHA. In fact, the

conversion of ALA to DHA is so limited in men that

consuming more ALA (from flaxseed oil, for example) may

not increase DHA in the brain at all. Women, on the other

hand, are approximately 2.5 times more efficient at

converting ALA, an ability thought to be facilitated by

estrogen to support the needs of future childbearing.

Unfortunately, the capacity to create DHA from ALA may

partly decline as a result of menopause, perhaps playing a

role in the increased risk that women face for both

Alzheimer’s disease and depression.

27

Factors other than gender influence the conversion of

plant-based ALA to DHA and EPA. People of European

origin who possess “newer” genes (they just don’t make

’em like they used to) may have reduced conversion

abilities compared to those of African descent—it’s possible

that the ability to convert plant forms of ALA became

relegated with the increasing availability of more reliable

sources of omega-3s from meat, fish, and eggs.

28

Ironically, and adding to the considerable consequences

of polyunsaturated oil consumption, the enzymes that

convert ALA to EPA and DHA also convert linoleic acid,

the predominant omega-6 fat in the diet, to its usable proinflammatory form (called arachidonic acid). These

benevolent worker chemicals are indifferent to our needs—

they just convert what we feed them, and today, we’re

feeding them mostly omega-6s. In the case of people who

get little preformed EPA and DHA and lots of omega-6s

from their diets (vegans who consume lots of processed

foods, for example), the brain may actually become omega3 deficient for this reason.

To eliminate the guesswork when it comes to nourishing

your brain with EPA and DHA, I suggest the “set it and

forget it” method: be vigilant in your avoidance of

polyunsaturated oils—corn, soy, canola, and other grain and

seed oils—and ensure that you’re getting preformed EPA

and DHA from whole-food sources like fish (wild salmon

and sardines are great, low-mercury choices), pastured or

omega-3 eggs, and grass-fed beef. On days that you are

unable to get your dose of preformed EPA and DHA,

supplemental fish, krill, or plant-based algae oil may help.

Once you cover those bases, ALA from whole-food sources

like walnuts, flaxseeds, or chia seeds is a great addition.

Monounsaturated Fats: Your Brain’s Best

Friend

As with polyunsaturated fats, the brain is rich in

monounsaturated fats, which form the brain’s myelin sheath.

This is the protective coating that insulates neurons and

allows for speedy neurotransmission. However, unlike

polyunsaturated fats, monounsaturated fats are chemically

stable. Oils composed primarily of these fats not only are

safe to consume but seem to have a number of positive

effects in the body. Some common sources of

monounsaturated fat include avocados, avocado oil, and

macadamia nuts, and the fat content of wild salmon and

beef is nearly 50 percent monounsaturated. But perhaps the

most famous source of monounsaturated fat is extra-virgin

olive oil.

In Mediterranean countries such as Greece, southern

Italy, and Spain—where rates of neurodegenerative diseases

like Parkinson’s and Alzheimer’s are lower—extra-virgin

olive oil is the ultimate sauce, used liberally on steak, beans,

vegetables, bread, pizza, pasta, and seafood, in soups, and

even in desserts. My friend Nicholas Coleman, chief

oleologist at New York City’s Eataly, painted the picture for

me: “They don’t drizzle olive oil; they pour it on.”