Vitamin C for colds: Debunking the myth of mega-doses

Vitamin C for colds: Debunking the myth of mega-doses

It's a common opinion held by many that taking high doses of vitamin C for colds is as effective and logical as melting an ice cube under the sun. Or is it? Here's why this is one of the most widely spread myths in the world.

The first thing many parents do when their kid gets a cold is to give them a dose of vitamin C, or at the very least, a big glass of orange juice. It’s the same for you – those first sniffles or sneezes call for vitamin C. But, is vitamin C for colds really effective? 

According to science, it is not. 

But how did the world get the idea that vitamin C is supposed to help alleviate colds — if not cure it? Is it vitamin C manufacturers trying to sell us more vitamins? Is it the citrus fruits industry? Could it be a conspiracy?!? We delve into the truth about vitamin C.

Vitamin C for colds is a cure-all?

vitamin C for colds

Vitamin C for colds? | Image Source: File Photo

The truth is, vitamin C is rarely harmful so there’s no strict restriction on it.  This only cements the notion that it’s a cure-all.

“There’s a lot of misinformation out there on vitamin C because it’s safe,” says Heather Mangieri, a nutritionist who works with the Academy of Nutrition and Dietetics.

If you really want to get to the bottom of this notion, you can trace it to Nobel-prize winning scientist Linus Pauling. He believed that vitamin C could cure numerous unrelated ailments. His belief persists to this day, and it’s one that’s believed by millions.

Discovery of vitamin C for colds and scurvy

You have to remember that there was a time when people didn’t know that vitamin C existed. 

However, they did know about scurvy. We now know that this condition is an extreme vitamin C deficiency that commonly plagued seafarers. Sailors on long voyages were often short on fruits and vegetables. Without them, they didn’t get vitamin C in their diets, so they contracted scurvy. This usually results in swollen extremities and painfully inflamed gums.

Between 1500 and 1800, there were around two million sailors who died of scurvy.

In 1747, scientist James Lind stumbled upon a solution to scurvy through trial and error. While testing different ways to cure scurvy, he found that the most effective treatment was oranges and lemons.

Oranges and lemons, vitamin C for colds

Even with that discovery, it took almost two more centuries before scientists figured out what exactly was in oranges and lemons that cured scurvy.

In 1928, Hungarian scientist Albert Szent-Gyorgi discovered a substance that adrenal glands naturally produce and called it hexuronic acid. Three years later in 1931, American biochemists J.L. Svirbely and Charles Glen King discovered that the crystalline vitamin C in lemon juice matched the properties of hexuronic acid.

Then came Linus Pauling, the only person to ever win two unshared Nobel Prizes. 

Non-expert recommends vitamin C for colds

During a talk in 1960, Pauling mentioned that he hoped to live another 25 years to witness the newest discoveries in science. A man in the audience, Irwin Stone, responded to Pauling’s remark in a letter. He recommended that Pauling take 3,000 mg of vitamin C to live longer.

Pauling said afterward that he did begin to feel livelier and healthier” after taking Stone’s advice.

The problem here is that Irwin Stone isn’t an expert in anything. But Pauling was already convinced.

“In particular, the severe colds I had suffered several times a year all my life no longer occurred,” Pauling was noted as saying.

In the following years, he raised his vitamin C intake up to 18,000 mg per day (which is already 18g of vitamin C already). Since then, he became obsessed with Vitamin C.

A book on vitamin C for colds

This obsession culminated in 1970 with the release of Pauling’s book, Vitamin C and the Common Cold, which encouraged readers to consume at least 3,000mg of vitamin C daily.

“Unfortunately, many laymen are going to believe the ideas that the author is selling,” Franklin Bing wrote in a scathing review of the “irritating” book in the Journal of the American Medical Association. 

History shows us how right Bing was.

For instance, a January 1971 article by The Bulletin reported the dramatic rise in sales of vitamin C supplements.

“Pharmacist Bob Gabriel reported that people are not only buying more vitamin C, but are asking for it in higher dosages because of Dr. Pauling’s assertions. Before 100 mg tablets were the common purchase. Now 250 and 500mg sizes are the first to go.”

Pauling made exaggerated claims that said how vitamin C can eliminate the common cold, retinal detachment, snakebites, and the AIDS virus. He even made dubious tests trying to prove vitamin C’s efficiency in curing ailments, but these were later debunked by scientists who criticized his unscientific methods and tried to replicate his tests to no success.

Vitamin C for colds does not work

Scientists have repeatedly found that high amounts of vitamin C do not slow the progress of colds.

A Cochrane review of nearly 30 studies looked into people with colds who took the normal daily dose of vitamin C and found that it only reduced the colds’ length by 8 percent. 

Researchers found no dramatic effects of vitamin C supplements on lowering the risk of cancer. Scientists also encountered the same problem when they tried to establish a correlation between pneumonia and vitamin C.

“Lots of people have tried to feed high levels of a single nutrient like vitamin C and look at anything from cardiovascular disease to cancer to cataracts, and most of those trials have been very disappointing,” said Dr. John Erdman, a nutrition researcher.

The risk of overdosing on vitamin C for colds

Apart from being highly ineffective at large doses, “mega-doses” of vitamin C come with risks.

The National Institutes of Health said people shouldn’t take more than 2,000mg per day. Any higher and you could get stomach cramps, nausea, and diarrhea.

That’s not all. In one study, Swedish researchers discovered that men taking vitamin C were twice as likely to develop kidney stones compared to people who don’t.

So why do we still take them? 

When the vitamin industry has an opportunity to broadcast news, distribute literature, anything else, it takes that opportunity,” said Dr. Stephen Barrett, retired psychiatrist of the accountability site

The problem here is that they’re not even regulated by local governments. Even the websites that promote these supplements say so themselves.

Alternative to vitamin C for colds

If you or your child has a cold, you don’t have to load them up on vitamin C to make them better. There are more effective ways to ease their discomfort like the following:

  • Putting saline (saltwater) drops in the nostrils to relieve nasal congestion
  • Running a cool-mist humidifier to increase air moisture
  • Dabbing petroleum jelly on the skin under the nose to soothe rawness
  • Giving cough drops to relieve sore throat (only for kids older than six years)
  • Putting a towel over the head and inhaling steam from a basin/bowl of hot water, while using drops of a plant oil such as eucalyptus or olbas oil for added relief
  • Running a warm bath or use a heating pad to soothe aches and pains
  • Eating a hot (but not too hot!) bowl of chicken soup or any sort of soup

Make sure your child eats when he’s hungry. Give him plenty of fluids like water or fresh fruit juice to help replace fluids lost during a fever.

Is it a cold or the flu?

vitamin C for colds

How to differentiate flu from common cold | Picture by the Center for Disease Control and Prevention

Remember, though the flu and the common cold are both respiratory illnesses sharing many symptoms, they are caused by different viruses. It can be difficult to tell them apart, but usually, the flu is worse than a common cold.

Common colds usually cause a runny or stuffy nose, but do not result in serious health problems like pneumonia, bacterial infections, or serious complications that lead to hospitalization.

The symptoms of flu may include fever or chills, cough, sore throat, runny or stuffy nose, muscle or body aches, headaches and fatigue.


National Institutes of Health

Centers for Disease Control and Prevention




YOU CAN ALSO READ: 5 Reasons why your child is always hungry

Republished with permission from: theAsianParent Singapore


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