When there is a lack of vitamins in the human body, the body will have various adverse reactions, which seriously affect our daily life and work, not only that, but the lack of vitamins also has an extremely adverse impact on physical health.
In order to solve this problem, the sales market of vitamins came into being, and more than 80% of merchants are using marketing methods to vigorously promote the miraculous effects of vitamin health products, claiming that they can not only enhance immunity, but also anti-aging.
However, the question is, are these vitamin complexes and other nutraceuticals good or bad for the body when consumed regularly? In response to this question, the doctor gave a clear answer.
The definition of vitamins is: "a class of organic compounds necessary for the maintenance of normal life activities of the human body, which can be divided into fat-soluble vitamins (vitamins that can be dissolved in fats) and water-soluble vitamins (vitamins that can be dissolved in water, are easily excreted in urine, rarely overdose, and need to be ingested in moderation for a long time)".
1.Rough
If you usually pay more attention to maintenance, but you still have problems such as dryness, enlarged pores, and red acne, it may be that the body is reminding you that you are deficient in vitamin A, vitamin C and other substances.
2.Insomnia, anxiety, depression
Psychological problems such as insomnia, anxiety, and depression are becoming more common, and these problems may be related to vitamin deficiencies. Vitamins B1, B3, B6, B9 and B12, among others, are essential for nervous system health, and deficiencies in these vitamins can lead to psychological problems. 
3.Bleeding gums
Vitamin C is key to gum health, and it helps maintain the structure and function of gum tissue. If you are deficient in vitamin C.
Your gums may bleed easily due to a lack of supporting tissue, and even swollen gums and loose teeth may occur. To keep your gums healthy, you can eat more fruits that are rich in vitamin C, such as citrus fruits, strawberries, etc.
4.Canker sores
Canker sores are a common disease in life and can easily occur. However, if mouth sores occur frequently and are difficult to recover for a long time, then it is necessary to consider whether it is caused by a lack of vitamin B2 in the body. Because when there is a lack of vitamin B2 in the body, it is easy to cause the body's resistance to deteriorate. 
We need to analyze the question of whether too much vitamin intake will cause damage to the liver. Different types of vitamins are metabolized and excreted differently in the body, and excessive intake of certain vitamins may be a burden on the liver, but it does not necessarily cause harm.
Excessive intake of vitamin A and vitamin D may cause some burden on the liver, but as long as the intake does not exceed the safe range, it generally does not cause serious harm to the liver.
For some other water-soluble vitamins, such as vitamin C, vitamin B, etc., because they can be excreted through the urine, excessive intake generally does not cause harm to the liver.
1.Vitamin D
Vitamin D plays a key role in maintaining bone health, but long-term excessive intake of vitamin D may cause symptoms such as hypercalcemia and irregular heartbeat. For most people, vitamin D needs can be met through sun exposure and a balanced diet.
2.Vitamin A
Vitamin A is a fat-soluble vitamin, and its excessive intake can lead to accumulation in the body, which puts a burden on the liver.
The liver is the main organ of vitamin A metabolism, and long-term excessive intake of vitamin A will inhibit the activity of some enzymes in the liver, affect the normal metabolic function of the liver, and then lead to liver damage.
Excessive intake of vitamin A will be stored in the liver like fat, causing the liver to bear more metabolic burden, and in the long run, the burden on the liver will become heavier and heavier, which may eventually lead to liver damage or fatty liver.
3.Vitamin C
Although vitamin C has many benefits for the human body, long-term high intake can also have negative effects on the body. Excess vitamin C can cause symptoms such as diarrhea, stomach pain, stones, etc. It is recommended to consume a moderate amount of vitamin C through food and avoid long-term overdose.
4.Vitamin E
Vitamin E can inhibit the oxidation of fatty liver, excessive supplementation will cause poisoning, but also lead to blood clots or high blood pressure, long-term consumption of vitamin E, is likely to cause dizziness, limb weakness and other adverse reactions.
In order to avoid these situations, it is recommended that when you supplement vitamin E, you must control the dosage and do not overdose for a long time.
Picky eaters or people with irregular diets: These people may be nutritionally deficient in 2 or 3 vitamins and therefore need to take vitamin supplements, but they need to know which type they should supplement.
Elderly: As you get older, your body's metabolism and nutrient absorption will be greatly reduced, so if you want to maintain balanced nutrition, it is necessary to make certain supplements, including vitamins.
Pregnant women: Pregnant women have high nutritional needs, and pregnancy reactions during pregnancy will reduce the intestinal absorption of nutrients, so it is necessary for them to supplement nutrition, including vitamins.
Compared with ordinary pills for a few dollars a bottle, people often prefer multivitamins of dozens or hundreds of yuan, on the one hand, they feel that expensive things are better, and on the other hand, they feel that the ingredients in them are more complete, and a little more is a little more.
If you're just vitamin C deficient, a few dollars pills will suffice your needs, spending more is not necessary, and it will also lead to an increased risk of excessive intake of other vitamins.
In addition, when choosing, you should not look at **, but should look at the approval number, don't buy health products, many health care products are not so magical, and the effect of eating cheap is the same.
In conclusion, moderate intake of vitamins and other nutrients is beneficial for your health, but long-term high intake of certain vitamins can be taxing on the liver.
In order to protect liver health, we should reasonably control the intake of nutrients, follow scientific and reasonable dietary guidelines, and avoid unnecessary supplementation and use of drugs with liver toxicity. If you have any concerns or symptoms of discomfort, you should seek advice from your doctor or professional promptly.