Bestselling author and one of our favorite docs, Dr. Ian Smith stopped by to celebrate the publication of his new book, The Ancient Nine, a totally gripping thriller that investigates members-only secret societies at Harvard. This book was 25 years in the making—he started writing it when he himself joined one of these exclusive clubs.

Wow!

Naturally, we couldn’t resist getting his expert opinion on some ancient medical myths, too, so he walked us through the science behind some old-school home remedies that we all grew up hearing.

Equipped with true or false paddles, our studio audience guessed whether each myth was true or false, before Dr. Ian hit us with the real deal.

RELATED: Dr. Ian Answers Your Most Pressing Health Questions

Can Sugar Be Used To Treat Hiccups?

First up, those pesky hiccups!

The Ancient Greeks believed, Dr. Ian told us, that one way to stop hiccups was to sneeze, hold your breath, to be scared or, to eat sugar.

So, we put the question to the audience, and they were pretty much split 50/50.

But Dr. Ian says that, in fact, it’s true!

How does it work? When the diaphragm, which he calls the most important breathing muscle in the body, spasms, your epiglottis (a small piece of cartilage which covers your vocal chords) closes down (the ‘hic’ you hear, he says, is the air not being able to pass through).

A teaspoon of sugar gets rid of hiccups, the doc explains, by stimulating the vagus nerve located in the throat, which makes the body forget to hiccup. The vagus nerve is a cranial nerve that conveys sensory information about the organs to the brain. When it's distracted by something else — like swallowing sugar — it tells the brain that something more important than hiccupping has come up so the diaphragm spasms stop.

Will Carrots Improve Your Vision and Make You See Better At Night?

This is one we’ve heard since childhood, but is it actually true?

The audience definitely thought so, and Dr. Ian revealed it’s both true and false! Carrots can help prevent eyesight deterioration because of their antioxidants, but they won’t restore 20/20 vision or help you see in the dark (eggs, citrus, peanut butter, and dark leafy greens also contain this important antioxidant called lutein), he says.

People started believing this during the World War II blackouts in London (which were issued by the government to make it more difficult for the German planes to hit targets), the doc explained. There was a pilot named Cunningham, he said, who was able to knock down enemy planes in the middle of the night, and they believed he was able to do that because he ate a lot of carrots.

We hit the learning jackpot: a history lesson and some medical myth-busting!

RELATED: How Do I Get Rid of Hiccups?

Can Cranberry Juice Treat a Urinary Tract Infection?

Our viewers DEFINITELY thought so, but Dr. Ian totally busted this myth!

The story behind the myth, he said, is that for thousands of years, Native Americans actually used a poultice made from cranberries to help heal wounds and tumors. That was a smart strategy, he told us, as cranberries have a compound that prevents common bacteria like E. coli and Staph from attaching to the walls of tissue cells. There is an active ingredient in cranberries that can prevent adherence of bacteria to the bladder wall, particularly E. coli, but most of the studies have shown that juice and supplements don’t have enough of the active ingredient -- A-type proanthocyanidins (PACs) -- to prevent bacteria from sticking to the urinary tract.

If you’re suffering from a UTI, the doc says, see your doctor, and perhaps try a different, more pungent ingredient: garlic!

He advises putting a peeled garlic clove in hot water, (“Can’t you just have it with some spaghetti and olive oil?” joked Rach) and letting the nutrients seep into the water. It won’t taste good, he says, but the compounds in the garlic could help kill bacteria and ease discomfort.

He also warns against having coffee, alcohol or spices if you’re dealing with this uncomfortable condition, as he says that they’ll irritate your urinary tract further.

Author, doctor, myth-buster: what can’t Dr. Ian do?!

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