A friend of ours in Mexico city, named Fernando, is an expert in chilis, which of course originated in Mexico and permeates the food of that delicious country.

His theory is that the reason Mexican people are usually so happy and friendly is that they eat chilis every day, usually several times a day.

Wait, what?

This theory is based on two claims:

1. Chilis make you happy

2. Mexicans eat huge quantities of chilis

Are these claims true?

Chilis are spicy. This chemical burning sensation in the mouth is caused by capsaicin, found in tiny glands in the chilli's "placenta" -- that white spongy stuff surrounding the chili's seeds. There's no actual burning. Capsaicin tricks the burn-detection hardware in the mouth into believing that burning is going on.

Capsaicin receptors in the mouth (quantity and sensitivity of which is partly genetic) determines how "hot" chilis feel.

The pain of this capsaicin "heat" causes the the production of a neurotransmitter called substance P, which tells the brain that the mouth is experiencing pain from burning. The brain responds with neurotransmitters designed to reduce the pain, including endorphins and specifically dopamine, which makes you feel good and gives you an overall sense of wellbeing.

So, yes, chilis make you happy.

As a bonus, chilis are high in vitamin C (double what you find in citrus fruits), vitamin A, and b-carotene. They have antibacterial qualities, and contain bioflavonoids and antioxidants.

There's literally no downside to eating chilis, and everything about them contributes to real health and happiness.

But do Mexicans really eat more chilis than others? After all -- although chilis originated in Mexico thousands of years ago -- there's a global chili craze right now.

Again, the answer is: yes. Mexicans eat way more chilis than anybody else.

The average Mexican eats up to nine kilograms of chiles a year -- far more than the average citizen of any other country.

So it looks like our friend Fernando is really onto something. Mexicans eat chilis for breakfast, lunch and dinner. Mexico is a nation drunk on dopamine.

So pack your diet with chilis. And make yourself happy the Mexican way.

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