Vitamin A is known as the “vitamin for eyes and mucous membranes”. There must be a very close relationship between it and human vision and resistance. Research has found that the symptoms of night blindness are closely related to insufficient vitamin A in the human body. Insufficient vitamin leads to deteriorated vision. In simple terms, the reason why our eyes can sense light and color is entirely due to the rod cells and cone cells on the retina. Both rod cells and cone cells contain vitamin. Especially in rod cells, the light-sensitive pigment rhodopsin, the main component is vitamin A. When the human body lacks vitamin A, as a result, the content of rhodopsin will also decrease. As a result, weak light cannot be sensed.
For example, after you enter a movie theater, it takes a relatively long time for your eyes to adapt. This may very well indicate that you have insufficient vitamin A in your body. It is best to consume more foods rich in vitamin A. Moreover, people engaged in work such as typing and drawing are prone to eye fatigue. Onweekdays, they especially need to fully supplement vitamin A to protect the human mucosa from external invasion. In the human body, including the eyes, nose, mouth, gastrointestinal tract, bladder, urethra, skin, etc., there are all mucous membrane tissues. Therefore, how to properly protect the mucous membrane and prevent it from being invaded by external factors becomes an important mission of vitamin A. The formation of cancer cells often begins in the mucous membrane part of various organs of the human body. If there is a long-term lack of vitamin A, the mucus produced by the mucous membrane will decrease, leading to cell atrophy. The inner membrane of the organ thus becomes thinner and easily peels off. After peeling off, it not only becomes hard but also no longer has the function of a mucous membrane. Under such circumstances, cancer is naturally prone to occur. Scholars point out that parts such as the esophagus, lungs, and stomach where food and oxygen must pass are extremely prone to cancer due to mucosal mutations. Hepatitis A carriers should also fully consume it.
Professor Yuuki Hirayama, an authoritative figure in immunology in Japan, once put forward a similar research conclusion: “Among smokers, if they consume enough yellow-green vegetables (containing a large amount of beta-carotene, a precursor substance of vitamin A) every day, their cancer incidence rate is significantly lower than those who do not consume enough yellow-green vegetables.” In addition, experimental reports show that vitamin A can not only prevent the occurrence of the above-mentioned cancers, but its effectiveness in inhibiting the spread of cancer cells can also be expected.
In China, some scholars have proposed that vitamin A has the effect of protecting the liver. According to the joint research by Director Chen Jianren of the Institute of Epidemiology, School of Public Health, National Taiwan University, and Lecturer Xie Xiuxing of Chia Nan University of Pharmacy and Science, it is pointed out that if hepatitis B carriers can eat more yellow-green vegetables, the probability of developing liver cancer in the future is obviously only one-tenth of those who do not regularly consume them.
If there is insufficient vitamin A, the eyes will become dry (in severe cases, it mayeven lead to conjunctivitis), the skin will become rough and full of acne, it is easy to catch a cold (and it is not easy to cure), indigestion, and so on.
Cod liver oil is the richest in vitamin A. The recommended amount of vitamin A for adults is 5,000 international units (IU) per day.
Foods containing vitamin A: cod liver oil, liver, carrots, green and yellow vegetables, eggs, milk, dairy products, butter, yellow fruits.
Deficiency symptoms: dry eyes, night blindness, poor tear secretion, prone to respiratory infections, dry and rough skin, deteriorated mucosa, weight loss, poor bone growth, poor tooth enamel, diarrhea, slow growth.
*If vitamin A deficiency is not treated, it will eventually lead to blindness.
Symptoms of excessive intake: hair loss, stomach pain, vomiting, diarrhea, rash, bone pain, menstrual irregularities, fatigue, headache, enlarged liver, peeling skin, blurred vision, etc.
Effects:
1. Helps treat various eye diseases, including preventing night blindness and forming rhodopsin in the eye.
2. Promotes bone growth, tooth growth and regeneration.
3. Helps form and maintain healthy skin, hair, and mucous membranes.
4. Increases the human body’s resistance to respiratory infections.
5. When applied externally, it helps treat acne, small pustules, boils, carbuncles and ulcers.
6. Helps in the treatment of emphysema and hyperthyroidism.
Interaction with other substances:
Cigarettes: Reduce the absorption of vitamin A. Smokers need extra vitamin A.
Chronic alcoholism: Affects the transportation and use of vitamin A in the human body.
