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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Protein is essential for photosynthesis.

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The gene codes for a nourishing protein that is essential for the survival of motor neurons.

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Campbell said he grew up on a dairy farm and for a long time held to the belief that animal protein was an essential part of a healthy diet.

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If you don't eat eggs or milk, it is essential to incorporate some form of protein at all meals and snacks to meet your daily protein requirements.

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But fish is a good source of protein and the best source of Omega-3 fatty acids, which are essential for the development of a fetus.

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