Supplement Synopsis

I wish I could say the blessings I have been receiving were well wishes into 2024. Unfortunately, I have received multiple “bless you’s” that come following what seems to be a never ending round of sneezing. What a fun way to ring in the New Year!

With head colds, allergies, sinus issues, and other congestion causing illness that affect so many this time of year, along comes everyone’s favorite remedies. I had a short list of vitamins and supplements to talk about in this post, but once I started reading the research on vitamin C, I decided to make this post a 2 part blog post. This one will be only on vitamin C. Zinc, echinacea, garlic, quercetin, and elderberry will be covered in my next post.

Vitamin C

I will be honest, the research on vitamin C as a treatment for the common cold surprised me. I have done a lot of research on vitamins and supplements, but this may have been the first time I looked up vitamin C specifically for colds. I guess I always took it at face value that vitamin C is the best thing for a cold, because that is what has said since the 1970’s.

What surprised me is the research did not support vitamin C as a treatment for colds and the research was mixed on the effect with duration and severity of colds.

Vitamin C is known as an effective antioxidant- it protects neutrophils from oxidative stress during an immune response, plays a role in regulating inflammatory response, and protects from oxidative damage to lymphocytes. (1) With all vitamin C does for the immune system, a meta-analysis of 45 studies indicated vitamin C does not prevent the incidence of the common cold. (2). Another paper stated that with a viral infection, vitamin C may be beneficial, but the evidence to support that claim is limited. (3)

Several other meta-analyses showed results of a decrease in the duration and severity of a cold (4,5,6). One study (6) differentiated between severe and mild symptoms, and found that Vitamin C had a positive impact on duration with severe symptoms, but not with mild symptoms.

Considerations for Vitamin C

If vitamin C does not prevent a cold, but could shorten the time being sick and/or decrease the severity of the illness, is vitamin C supplementation warranted during a cold? Possibly.

Why possibly? There are many factors I consider here:

– does the diet already provide adequate amounts of vitamin C to support nutritional needs?

– is malnourishment a consideration?

– are the symptoms mild or severe?

– is a multivitamin containing vitamin C already taken?

The research varies on how much vitamin C should be supplemented to shorten the duration and severity of a cold. The RDA for vitamin C for 19 and older is 90 mg for men, 75 mg for women. Pregnant or lactating women and smokers require more vitamin C. Tolerable upper intake levels of Vitamin C for 19 and older is 2,000 mg a day. Megadoses should be avoided (unless under the care of a physician) to prevent vitamin C acting as a pro-oxidant, gastrointestinal issues such as diarrhea and nausea, or possible formation of kidney stones in those with hyperoxaluria.

Stay tuned to read about the other supplements I mentioned at the start of this post!