Did you ever wonder if certain foods have a direct effect on your health?

Well, I'm here to solve that mystery since you are the foods you eat.

Welcome to the Nutrition Facts Podcast. I'm your host Dr. Michael Greger.

Today we look at their old diet plays in preventing and treating mood disorders.

Depression affects more than 150 million people worldwide,

making it a leading cause of losing healthy years of life

as a result of disability. Why is depression so common? Well, it has said

nothing in biology makes sense except in the light of evolution, but why would we evolve

to get depressed?

Depression poses a baffling evolutionary puzzle

if it has such negative effects,

but yet it remains so common,

and inheritable, meaning a big chunk of risk

is passed through our genes,

so there must be some kind of adaptive benefit.

Otherwise, presumably, it would have been naturally selected against.

Maybe depression is an evolutionary strategy for defense against infection.

Infection has been the leading cause of mortality throughout human history.

The average of life expectancy was 25, and it was not uncommon for half our kids to die.

With such stark capabilities, infection has been a critical and potent driving force and natural selection.

When we become infected, there's a surge of inflammation as our body mounts a counterattack.

And then what happens? We feel lousy. We feel sick, we get

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