Moderation Is Best When It Comes to Vitamin C Intake

Vitamin C, also known as ascorbic acid, is necessary for the growth, development and repair of all body tissues. (Peangdao/Shutterstock.com)

During the cold and flu seasons, many people choose to buy vitamin C supplements in order to decrease their chances of getting sick.

Vitamin C, or ascorbic acid, is one of the many water-soluble nutrients that are found naturally in fruits and vegetables, and it is an antioxidant that is well-known to be capable of helping to prevent certain illnesses.

Vitamin C has also been shown to improve the immune system, inhibit melanin deposition, supplement wound healing, and prevent the occurrence of cardiovascular diseases or cancer.

More and more people are choosing to take vitamin C supplements as part of their daily regimen. So, is it true that the more vitamin C supplements you take the better? How will long-term vitamin C intake affect the body?

Recently, Taiwan’s Food and Drug Administration advised a moderate intake of vitamin C, with adults’ advised a daily intake of 100 mg, pregnant women at 120 mg, and breastfeeding mothers at 140 mg. Daily fruit and vegetable intake can provide sufficient amounts of vitamin C to the blood.

Excessive intake of vitamin C will reduce its absorption rate in the body. Surplus amounts of vitamin C in the body will be excreted in the urine and may cause severe gastrointestinal discomfort or kidney stones.

Many natural foods contain vitamin C. Adults who eat half a guava or a kiwi fruit daily will have enough vitamin C for the day, and if they want more, they can have 200-400 mg of vitamin C in their blood simply by having a few more fresh fruits and vegetables.

Fresh fruit and vegetable intake can also allow our body to absorb more phytochemicals, minerals, dietary fiber, and other ingredients that are beneficial to our health. Therefore, having fresh fruits and vegetables in our diet is preferred over taking supplements.

If You Take Too Much

So, what happens if you take excessive amounts of vitamin C?

Research shows that if you take more than 3,000 mg of vitamin C a day, the intestinal bacteria will metabolize the unabsorbed vitamin C, causing osmosis and diarrhea.

Other side effects could be more severe. Since the metabolite of vitamin C is oxalic acid, it may increase the risk of hyperoxaluria or even cause kidney stones.

Although taking excessive amounts of vitamin C above the upper limit is not life-threatening, it can cause significant side effects and discomfort.

In addition, vitamin C might interact with certain medications, especially cardiovascular and cancer drugs. Therefore, it is important to exercise caution and consult your physician before taking supplements with those drugs.

From a dietary point of view, people can choose the right amount of fruit to eat every day based on their preferences. As long as there is a balanced and diverse diet, there is no need for additional vitamin C supplements.

Vitamin C intake via fresh fruits and vegetables is sufficient and preferred for our bodies. Overall, frequent consumption of food that is high in vitamin C does not lead to any health issues.

However, taking excessive amounts of vitamin C supplements can cause side effects.