Is Emergen-C Bad For You?

Emergen-C is supposed to help you prevent and fight colds, although nowhere on their packaging do they say so explicitly. That's probably because Airborne, a similar product, was sued in 2008 for advertising that their product could help you get over a cold. The Federal Trade Commission decided there was no science to support that claim.

But what is Emergen-C? It's is a multivitamin that's built around a staggering megadose of vitamin C: 1000 milligrams, or ten times more than your body needs every day. According to the Mayo Clinic, the upper limit on Vitamin C dosing is 2,0000 mg a day. Most of the extra vitamin C from Emergen-C will be excreted from your body when you use the bathroom. The body can only process about 500 mg of Vitamin C, so half the Emergen-C packet is getting flushed away.

There's a chance, however, that you will experience temporary discomfort and some unpleasant symptoms from vitamin C megadosing. These symptoms are mostly stomach problems - diarrhea, nausea, bloating, cramps, tachycardia, even vomiting. Some studies have shown a correlation between vitamin C megadoses and kidney stones, which is a very high price to pay for a bunch of vitamin C your body won't absorb.

The notion that massive amounts of vitamin C can help fight colds can be traced back to Linus Pauling. He was a decorated 20th-century chemist with two Nobel prizes to his name - one for chemistry and one for peace. Pauling spread the idea that massive doses of vitamin C can help to prevent and treat colds and other ailments. 

Unfortunately, there's not much evidence to support this idea. That's not for a lack of research - according to Quackwatch, more than a dozen double-blind studies have tried to establish whether vitamin C can prevent colds. They found little evidence for that hypothesis. A meta-analysis conducted by Cochrane in 2005 concluded the same.

That's not to say the product is completely useless. If you're vitamin deficient, Emergen-C can help get you back to healthy levels. There's some evidence that vitamin C can help regulate cholesterol; unless you have unhealthy cholesterol levels, however, this won't make much of a difference. The same is true of those with asthma. Large doses of vitamin C can help, but in healthy people it makes little difference. If you're suffering from these conditions, don't self-medicate with Emergen-C: talk to your doctor and get proper medical treatment.

Taking vitamin C does stimulate production of antihistamines, which can slightly improve the symptoms of a cold, but you need only take the recommended daily dose: that's between 60 and 100 milligrams a day, which is about the amount of vitamin C you can find in a cup of chopped strawberries or broccoli. Emergen-C, in short, is overkill.

Vitamin C is water-soluble, so it passes out of your body through urine. Emergen-C also contains 25% of your daily B vitamins, which are not. If you're taking five or six packets a day, there's a chance that over time you could build up enough B vitamins to trigger toxicity symptoms that affect your liver and heart. Nobody should drink this much Emergen-C - remember, your body will max out with the vitamin C content of half a packet.