Vitamin C is really not a “panacea”

Some people joke that “drink more hot water, go to bed earlier, reboot” are the three ways to solve any problem, and vitamin C is quite the fourth place – when a person is sick, it is often said that Take some vitamin C, but is it really a panacea?

In life, I often hear such conversations:

“I feel like I’m sick……”
“Take some vitamin C…”
“I have an ulcer in my mouth…”
“Take some vitamin C…”
“I have a cracked lip…”
“Take some vitamin C…”

As an essential nutrient for the human body, vitamin C does have many important physiological functions. Naturally, it is indispensable, but it is not the more the better. In the case of paying attention to food selection and cooking methods, it can be obtained from a normal diet without additional supplementation.

Vitamin C, what is it?

Vitamin C, also known as ascorbic acid, the English name is Vitamin C or ascorbic acid, is an essential nutrient for humans and a few other organisms. Many animals can synthesize vitamin C from glucose, but humans can only get it from food. For this reason, please see the article “Why can’t the human body synthesize vitamin C by itself?” “.

Vitamin C is also the one with the largest daily requirement of all vitamins (for the average adult, the recommended dietary supply of nutrients for most vitamins is below 20 mg/day, while vitamin C is 100 mg/day) Vitamin C is usually only found in plant foods, and animal foods are basically free of vitamin C. All kinds of fresh vegetables and fruits are her main sources [1].

Food sources of vitamin C

The best food sources mainly include prickly pear, fresh jujube, kiwi, etc.;

Good food sources mainly include pepper, bitter gourd, citrus, tomato, cauliflower, strawberry, lychee, green leafy vegetables, etc.;

General food sources mainly include cabbage, celery, lettuce, pumpkin, pear, apple, banana, peaches, cherries, etc.;

Scarce food sources include animal foods such as livestock and poultry meat, fish, eggs, and milk, and several plant foods such as dried soybeans.

What is vitamin C good for?

1. Promote collagen formation

Collagen is a protein that is distributed between connective tissue, blood vessels, and bone and dentin cells, and is the basic support material for animal body size. So it keeps cells tightly packed, skin firm, and bones and teeth strong. After trauma or surgery, it can help cells repair and promote wound healing.

2. Enhance immune function

Vitamin C can promote the formation of antibodies and increase the concentration of antibodies such as IgA, IgG and IgM in the blood. These antibodies attach to foreign viruses and bacteria, directing white blood cells and lymphocytes to destroy them.

3. Promote mineral absorption

Vitamin C can promote the absorption of calcium, phosphorus, iron, and other minerals in the small intestine, so it is very helpful for those with anemia or osteoporosis.

4. Reduce arteriosclerosis

Vitamin C can strengthen the organization of blood vessels and reduce the content of cholesterol in the blood. It has a good preventive and therapeutic effect on atherosclerotic cardiovascular diseases, hypertension, stroke and other adult diseases.

5. Antioxidant Free Radicals and Antioxidant

Vitamin C is a strong antioxidant substance, which can effectively remove free radicals generated by long-term exposure to adverse environments [2].

6. Anti-tumor effect

The medical community believes that free radicals are related to the occurrence of cancer or aging. Nitrite amine is a carcinogen, and if there is sufficient vitamin C in the body, it can prevent the nitrous acid from the nitrous acid cured meat from the cured food to be converted into nitrous amine [3].

What happens if you are deficient in vitamin C?

The most well-known consequence of vitamin C deficiency is scurvy. Hundreds of years ago in Europe, sailors who sailed at sea for a long time often suffered from scurvy. Patients often suffered from bleeding gums, even skin congestion and oozing, and finally died in pain. People have never been able to find the cause. Strangely enough, the disease quickly cleared up as soon as the ship docked. A ship doctor found through careful observation that it was difficult for sailors to eat fresh fruits and vegetables during sailing. This may be why the sailors were sick at the time.

The doctor tried to get the sailors to eat some fresh citrus every day, and a miracle happened – the scurvy was quickly cured.

Scurvy is mainly manifested as malaise, loss of appetite, spotting bleeding on the skin, and even the formation of hematoma or ecchymosis. At the same time, the gums are swollen and inflamed. In addition, osteoporosis is also a manifestation of scurvy.

If the gums often bleed or collide with no force when brushing your teeth, you will have black blue and blood stasis on your body. At this time, you need to be alert to vitamin C deficiency.

Vitamin C, do you want to supplement it?

In theory, people can get enough vitamin C from food.

But if you choose too few foods containing vitamin C in your daily diet, you may not be able to get enough vitamin C from your food. Other lifestyle habits can also cause the loss of vitamin C in food. Vitamin C is water-soluble, and part of it is lost when rinsing and soaking; vitamin C is easily oxidized and cannot be stored for a long time; vitamin C is not resistant to high temperature, and it will be lost in large quantities if the heating temperature is too high or the time is too long.

At the same time, some individual reasons may also lead to the lack of vitamin C, such as the relative increase in body requirements and the decrease in absorption and utilization: pregnant and lactating women, children in growth and development, and patients in recovery from disease. The gastrointestinal function of the elderly is reduced, and the absorption and utilization rate of vitamins is reduced. Under these circumstances, it is easy to cause a lack of vitamin C. At this time, appropriate supplementation is also beneficial.

Vitamin C, the more the better?

After learning about the many benefits of vitamins, many people develop the habit of taking vitamin C daily. In fact, eating too much vitamin C can have serious consequences.

blood system

Long-term high-dose vitamin C can promote iron absorption, can cause high iron red blood cell anemia, and can also reduce intestinal absorption of vitamin B12, which accelerates the deterioration of megaloblastic anemia. If the daily dosage exceeds 5 grams, it can lead to hemolysis, which can be fatal in severe cases. Sudden withdrawal of vitamin C after long-term high-dose administration can cause rebound scurvy. Former Soviet medical scientist Lavlentsky pointed out that excessive intake of vitamin C will increase the risk of thrombosis.

digestive system

Long-term oral intake of vitamin C exceeding 3 grams per day can cause hyperperistalsis, diarrhea, abdominal pain, and in severe cases, gastrointestinal bleeding; it can increase gastric acid, often aggravating gastritis and gastrointestinal duodenal ulcers.

immune system

Excessive intake of vitamin C will significantly reduce the disease resistance of white blood cells. Too much vitamin C around the white blood cells not only prevents the white blood cells from destroying germs, but also protects germs and cancer cells, thereby reducing the body’s immunity. Excessive intake of vitamin C can delay the course of certain infectious diseases and allergic diseases such as rheumatism.

urinary system

Taking too much vitamin C may cause the formation of oxalic and uric acid stones. In sensitive individuals, it can also cause hyperuricemia and accelerate the formation of kidney and bladder stones.


Brier’s research team at the Center for Cancer Pharmacology at the University of Pennsylvania pointed out that vitamin C induces certain components that damage DNA, and these components can be found in various tumors, indicating that excessive vitamin C may have carcinogenic effects. Tumors and cancer have a dual role [2].

In addition, vitamin C also has contraindications. Some studies have found that vitamin C cannot be used together with a variety of trace elements, pantoprazole sodium, etc. [4]. Another study found that instillation of vitamin C before testing blood sugar, total cholesterol, triglycerides, and uric acid could lead to false reductions in the test results of the above indicators [5].

Precautions for dietary vitamin C supplementation

1. Choose some food raw materials rich in vitamin C, such as pepper, bitter gourd, citrus, tomato, cauliflower, green leafy vegetables, etc.;

2. Reduce the food cooked by heating, it is best to choose raw food. In this way, the loss of vitamin C during the cooking process can be avoided, and the heating temperature and time should be controlled for the food that needs to be heated.

3. It is best to eat the dishes immediately after the cooking is completed to reduce the damage to vitamin C caused by further heating and reheating of the residual temperature of the dishes;

4. If you cannot get enough vitamin C in daily food, you need to take vitamin C supplements, and you should also pay attention to the daily dose. The dietary reference intake recommended by the Chinese Nutrition Society is 100 mg/day for adults, and the tolerable maximum intake is 1000 mg/day.


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