-What did you say? -Orange juice.

It's for when you're feeling hot, and not so hot.

Don't you worry about Suzie getting enough Vitamin C?

Many people reach straight for orange juice when they get a cold.

Or mix up one of these cold busting, immune-boosting supplements packed full of Vitamin C.

It's supposed to help cure the common cold.

They're a growing two-hundred-million dollar industry.

And, unsurprisingly, their sales peak when the cold and flu season does.

And with boxes that claim that Vitamin C helps support your immune system, why wouldn't you pop a fizzy tablet when you start to feel a bit stuffy?

But if you follow these little asterisks, you'll see that the claim isn't supported by the FDA.

That's because Vitamin C doesn't cure your cold.

A powerhouse of Vitamin C!

You really crave orange juice and that craving is your body wisdom.

My what?

You just can't beat that great taste.

You can trace the Vitamin C craze back to this guy: Linus Pauling.

He was a pretty big deal.

He won a Nobel Prize for his work with quantum chemistry and a Nobel Peace Prize in the 60s for his anti-nuclear weapon advocacy.

So when he came out with a book in 1970, claiming that Vitamin C could help you avoid colds and improve your health, it took off.

Americans cleared drugstore shelves.

Newspapers wrote that the sales were "not to be sneezed at" and called it "The Great Cold Rush.”

But the medical community was cold to Pauling's cold claims.

For one, they weren't based on any actual science. Pauling had personally started taking Vitamin C at the suggestion of a friend, and he got less colds.

The criticism, of course, was that just because it happened to him, it didn't make it a real study.

Which Pauling admitted to, and asked that "someone" actually do one.

But doctors already knew that taking large amounts of Vitamin C wasn't the best idea.

Adults only need 75-90 mg of Vitamin C a day.

It's found in a ton of different foods.

Most people are eating enough Vitamin C in their normal diet for a healthy immune system.

But Pauling's book suggested taking 2,000 mg or more a day.

22 times the amount you really need.

Just because Vitamin C is good for you, doesn't mean that taking more is better for you.

A review of 46 different scientific trials with more than 11,000 participants found that taking Vitamin C supplements regularly doesn't prevent you from getting colds.

It can reduce the length of your cold by a meagar 8 percent — less than half a day.

But taking a supplement at the beginning of a cold doesn't help make it go away faster.

Vitamin C was found to be most useful for people engaged in "intense physical exercise", like marathon runners.

But for most people, "routine supplementation is not justified.”

And taking extra Vitamin C can result in a classic "too much of a good thing.”

That 2,000 mg Pauling recommended is the amount in two Emergen-Cs.

It's also the threshold of how much you can take before you may start to feel cramping or have diarrhea or nausea.

It could get worse.

A Swedish study found that men who took just 1,000 mg of Vitamin C a day were twice as likely to develop kidney stones.

But that's about as bad as it gets.

The reason this hasn't been more highly regulated, is you can't seriously hurt yourself with Vitamin C.

No one has died from an overdose.

Pauling himself said he used to take up to 30,000 mg.

It probably gave him tummy troubles, but he was otherwise fine.

So what will help your cold?

For one, hydration.

Sure, you can still have that orange juice, but just plain water or clear broth will do the trick, too.

Things like decongestants, ibuprofen, vapor rubs, they help ease the symptoms of a cold, but don't necessarily shorten it.

The best way to cure a cold is rest.

Let your immune system do its thing.

And don't worry too much about Vitamin C.