No, and yes. But mostly no.
Let me explain…
Maybe you can relate: growing up, I always took a Flintstone’s chewable multivitamin tablet with breakfast. As a teenager, I bought the gummies and ate probably six or seven at a time so I could feel virtuous about eating gummy bears. [I don’t recommend doing this…] But I didn’t really ever stop to think what the point of taking vitamins was or what they did for my body until supplements started gaining popularity — Emergen-C being one of them. Essentially, Emergen-C is a high-dose vitamin C powder (with a few other vitamins thrown in) that is advertised under the premise that it can be used to prevent or treat colds. Of course, the company doesn’t technically make these claims, but it’s the idea that most people take away from a statement like “supports the immune system and general health.”
Most people that I talk to think Emergen-C is like a “natural cold medicine.” Those who use it typically do so after they start feeling sick, or if they have been around someone who has cold/flu symptoms.
The truth is, Vitamin C does play a role in the immune system, but taking it in high doses doesn’t prevent you from catching a cold, and definitely doesn’t “treat” cold and flu symptoms. What most people don’t know is that it also plays another, very important role in the body, totally separate from runny noses and sore throats. I’ll explain this more thoroughly below, but here’s the main idea if you aren’t interested in the scientific detail.
Vitamin C needs to be taken daily to promote immunity. It doesn’t do anything for you if you’re already sick.
High doses (more than 500 mg/day) are ineffective
Vitamin C plays a role in heart health: research has shown that it can lower LDL cholesterol, and it is associated with reduced risk of heart attack and stroke.
If you want to supplement, 500 mg chewable tablets may benefit. I take on daily, and my favorite kind is pictured below. I think it was $6 for a 3-month supply.
Vitamin C and Immunity
Vitamin C (ascorbic acid) is not prophylactic against the common cold — or any infection, for that matter. The role of ascorbic acid in the body is to serve as a cofactor for numerous enzymes, meaning it participates in chemical reactions, especially by giving off reactive chemical groups. One of the most important functions of Vitamin C is serving as an anti-oxidant, meaning it prevents cells and tissues from being destroyed either by external, environmental factors, or by internal processes.
White blood cells, which are the active cells of our immune system in fighting off infections, store Vitamin C. The stored Vitamin C (antioxidant) helps protect them from destruction, and keeps them alive and active for a longer period of time. The longer white blood cells stay in our blood, the more opportunity they have to kill bacteria and viruses.
When we get sick, our body produces even more white blood cells, which fight off the infection with intensity. These cells need a certain amount of vitamin C to be effective, but only a very small level. (Most people already get enough vitamin C for a healthy immune system.) Taking extra Vitamin C doesn’t do much for us in terms of building up the army of white blood cells that are produced in response to infection. However, taking Vitamin C on a daily basis allows the white blood cells that are already in our blood to store up extra ascorbic acid to be used as an antioxidant. This helps them live longer and fight off infections a little bit faster. That’s why a supplement is beneficial in promoting immunity, but only if we are taking it before we get sick.
High Dose Vitamin C and Cardiovascular Health
The recommended dietary allowance (RDA) for Vitamin C is 75 mg/day and 90 mg/day for women and men, respectively. However, research has shown that the antioxidant effect of taking 500 mg per day is effective in lowering LDL cholesterol and preventing cardiovascular disease.
Cholesterol is problematic in our blood when it becomes oxidized. When this happens, our immune system doesn’t recognize it, and attacks it. This forms plaques, which stick to our inflamed blood vessels. This is how blocked blood vessels form — which lead to ischemia, strokes, and heart attacks. Since Vitamin C is an anti-oxidant, it prevents cholesterol from becoming oxidized, prevents immune attack, plaque formation, and reduces the subsequent cardiovascular risk.
How to Supplement
500 mg is the highest effective dose of Vitamin C. Taking more than this in one day can’t be absorbed because the blood already has the maximum amount of Vitamin C. As a result, extra Vitamin C is excreted in the urine or the bowel. (1,000 mg or more, such as the amount in Emergen-C, can cause diarrhea, but isn’t usually dangerous.)
If you’re interested in supplementing, research suggests that 500 mg, taken daily with food will benefit most people. Chewable tablets are way less expensive than Emergen-C, which costs more than $10 for a month’s supply. I don’t recommend taking pills, because they’re difficult to digest, and usually just pass through the body without being absorbed. [If you already own Emergen-C, cutting the dose in half and using it until you run out is a much more effective and affordable use. After that, get some chewables.]
Most importantly, talk to your doctor before starting a new supplement regime. Even though you don’t need a prescription for most supplements, they can have dangerous drug interactions, and some people may respond negatively. (For example, it is not recommended to supplement with vitamin C if you are prone to kidney stones.)