In recent years, the interest in supplements seems to be growing year by year.
However, there are two major problems with current supplements and health foods.
- Regulations are much more lax than for pharmaceuticals. This means that ineffective products are easily available at high prices.
- There is less research data than for pharmaceuticals. In other words, no one can say for sure about the long-term dangers.
As a result, many people are forced to pay unnecessarily high prices for health foods that not only have no effect, but may even shorten their lifespan in the long run.
The only way to prevent this from happening is to somehow sort out what we know and what we don't know, based on scientific evidence.
So, based on reliable data, we will look at supplements that have the potential to harm the body.
In the last issue, I introduced the results of a study on multivitamins.
Supplements that should be taken with caution: Multivitamins
In this article, I would like to discuss vitamin C.
Vitamin C doesn't have much of an effect.
Vitamin C is one of the best-selling supplements in the world.
It is said to be “good for preventing colds” and “good for beautiful skin,” and various benefits are advertised.
Especially in the past few years, there has been an increase in the number of claims that high vitamin C intake (5~10g/day) is anti-aging.
It continues to grow in sales as a standard health supplement.
However, reliable data shows that vitamin C has little to no effect.
For example, a paper published in 2005 surveyed all vitamin C studies from the 1940s to 2004 and concluded that they were quite accurate.
Robert M Douglas , et al. (2005)Vitamin C for Preventing and Treating the Common Cold
There are two key points that this study has drawn out.
- No amount of vitamin C can prevent colds for the average person.
- Athletes can use vitamin C to prevent colds.
In other words, the only people who can benefit from vitamin C are athletes who are physically overworked on a regular basis.
It doesn't seem to be worth the trouble for the average person who doesn't exercise that much to drink.
Next, let's look at the question, “Can vitamin C prevent aging?” Let's take a look at the question, “Can vitamin C prevent aging?
In fact, there is still no unified view on this question in the scientific community.
So far, the results have varied from experiment to experiment, so all we can say is “I don't know.
As an example, an experiment in which 386 men and women took 1g of vitamin C per day for two months showed a decrease in CRP (a number that indicates aging in the body), while an experiment in which 941 men and women took vitamin C for about 12 weeks showed no particular change.
It is still impossible to make a decision in this state.
Block, et al. (2009) Vitamin C treatment reduces elevated C-reactive protein.
Knab AM, et al. (2011)Influence of quercetin supplementation on disease risk factors in community-dwelling adults.
Vitamin C doubles the chance of getting cataracts?
In recent years, there have been allegations that vitamin C supplements may be bad for the eyes, while no significant effects have been observed. In recent years, there have been suspicions that vitamin C supplements may be bad for your eyes.
A 2013 study in Sweden tracked the effects of vitamin C supplements in about 55,000 men and women for eight years.
Rautiainen S, Lindblad BE, Morgenstern R, Wolk A. (2010) Vitamin C supplements and the risk of age-related cataract: a population-based prospective cohort study in women.
Compared to the group of people who did not take supplements, those who took vitamin C regularly had a 1.36 to 1.38 times greater risk of developing cataracts.
This risk is higher for the elderly, with the figure rising 1.96 times for those over 65.
The average vitamin C intake is about 1 gram per day, which is not even a small amount.
Nonetheless, it is surprising that the risk of cataracts increases.
The reason for this harm is unknown, but the most popular theory at the moment is that it is because vitamin C is converted into a toxic substance. This is the theory.
Vitamin C is a highly antioxidant substance, but in doing so, it turns itself into free radicals (highly toxic substances).
This is a well-known story in the world of chemistry, as William Porter, a food chemist, wrote in 1993.
William L. Porter (1993)Paradoxical Behavior of Antioxidants in Food and Biological SystemsVitamin C is like Janus or Dr. Jekyll and Mr. Hyde with two faces. As an antioxidant, it's a contradiction in terms.
This means that vitamin C, which is supposed to be good for you, can become bad and attack your cells.
Of course, the relationship between vitamin C and cataracts is not yet that well-established a theory.
However, it is worth keeping in mind as an example of the dark side of vitamin C.
Vitamin C supplements can cause a great deal of tooth decay.
Another disadvantage of vitamin C supplements is that they can cause tooth decay.
This fact was demonstrated in a study published by a Chinese university in 2012.
Haifeng Li,, et al. (2012) Dietary Factors Associated with Dental Erosion
We scrutinized data from a large amount of past research on “cavity-causing foods” and checked out the causes that tend to ravage teeth.
The result is that “soft drinks with sugar and vitamin C tend to cause tooth decay.
On the other hand, “milk and yogurt” was found to be effective in protecting tooth enamel.
This study is highly accurate in terms of data, and has a higher level of reliability than the “Vitamin C causes cataracts” paper I mentioned earlier.
For now, there is no doubt that vitamin C has a high risk of tooth decay.
The reason for this is simple: vitamin C is a type of acid called ascorbic acid.
Normally, tooth enamel begins to dissolve when the pH level drops below 5.5, but vitamin C has a pH level of around 2.3.
If you put roughly 500mg of vitamin C in your mouth, the pH level will remain low for the next 25 minutes, making your teeth vulnerable to damage.
If you take vitamin C in supplement form, refrain from brushing your teeth for at least an hour.
To sum up the above, first of all, vitamin C supplements have no noticeable effect, plus there is a risk of cataracts and tooth decay.
The cataract risk is still unclear, but in any case, vitamin C from fruits and vegetables should be sufficient.