There are three different but normal versions of the apo E gene and its protein, known respectively as E-2, E-3 and E-4.

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But 75% to 80% of people are born with at least one E-3 version of the protein, and more than half of people have two E-3's.

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The American College of Sports Medicine recommends that endurance and strength training athletes consume higher levels of daily protein than the standard recommended daily allowance (i.e. 1.2-1.7 grams of protein for each kilogram of body weight, versus 0.8 grams per kilogram per day).

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Vitamin E in particular can help boost collagen, a protein that gives skin its structure, she says.

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The Maya nut has high levels of nutrients including protein, calcium, fiber, iron and vitamins A, E, C and B.

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To come up with his index, Drewnowski ranked foods based on their concentrations of nine essential nutrients (protein, fiber, calcium, iron, magnesium, potassium, vitamins A, C, E).

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