Why is blood red and the blood vessels we see are blue-green? Few people know the truth

Everyone has blood vessels that carry oxygen and nutrients throughout the body. The blood vessels on the back of the hands, arms, and foreheads can be seen with the naked eye, showing blue-green color. Many people wonder that the blood vessels are red blood, but why do we see blood vessels with the naked eye to be blue or green? Let’s answer the doubts.

Blood is clearly red, why are blood vessels blue-green?

When the blood contains sufficient oxygen, the blood appears bright red; when the oxygen in the blood is exchanged with the carbon dioxide in the tissue, the bright red blood will gradually turn into a dark red.

The blood vessels seen by the naked eye are all veins. Blue light is difficult to penetrate the skin and is easily reflected. The wavelength of the reflected light determines the color seen by the eyes. The blood vessels visible to the naked eye are generally concentrated in the arms and backs of the hands, the calves and temples, the insteps and the neck, etc., which are also known as blue veins in the folk, and blue veins are veins.

Whether the arteries or veins are not filled with blood, the blood vessels are slightly whitish; although the venous blood appears dark red, when it passes through the yellow skin, because the light is reversed, the red light is absorbed , the blue light is reflected, causing the color of the eyes to change, and the blood vessels seen appear blue-green.

Why do people say that the longer the blood vessel is, the longer the person will live?

Blood vessels are located in every part of the body. The root cause of cardiovascular and cerebrovascular diseases is blood vessels. Therefore, the better the elasticity of blood vessels, the longer people live. Usually, the following points should be done to protect blood vessels:

1. Adjustment of work and rest

It is well known that smoking is harmful to health. Organs are damaged to varying degrees, leading to various diseases, including vascular health. Smoking cessation can reduce the risk of cardiovascular and cerebrovascular diseases, such as coronary heart disease, to a certain extent. Therefore, smoking cessation action is imperative.

“Daily Mail” once had a study that pointed out that the longer young people sit, the arterial blood vessels will also harden, and arteriosclerosis is a heart disease. a precursor. So let’s step up and move! Expel harmful substances from the body through exercise.

2, multi-sport

Scientific exercise helps the body to be healthy and even fight against aging. We should ensure that the daily exercise time should not be less than 30 minutes, which can increase the basal metabolic rate, accelerate fat burning, improve lipid metabolism and glucose metabolism disorders, and help reduce the burden on blood vessels.

3. Dietary Modification

Diets high in fat, cholesterol, and sugar produce Excess calories, calories are converted into fat, resulting in elevated blood lipids. Lipids are easily blocked in the blood vessel wall, thereby damaging the vascular endothelium, leading to atherosclerosis and promoting thrombosis. Therefore, attention should be paid to a light diet and strict control of total caloric intake.

How to easily self-assess blood vessel health?

1, clenched, open fist

clenched fist tightly for 30 seconds, palm skin Gradually turn white; then immediately open the fist, as long as the color of the palm returns to normal within 3 seconds, indicating that the elasticity of the heart blood vessels is good; if the color of the palm recovers for more than 5 seconds, one should be alert to arterial blockage or arteriosclerosis.

2. Observing blue veins

The blue veins visible to the naked eye are venous blood vessels, and venous blood returns When blocked and the venous pressure increases, the veins will gradually bulge, especially on the back of the hand, arms and instep. To rule out the bulging of blue veins caused by weight loss and heavy physical labor, it is necessary to be alert to diseases, especially varicose veins.

3. Press the blood vessels in the middle of the soles of the feet

Gently press the upper and middle of the soles of the feet The blood vessels can generally feel the pulse beat obviously. If your pulse is weak or you can’t feel it, nine out of ten your arteries are blocked.

Message from the family doctor

Be good from a young age Take care of blood vessels, adopt a low-salt diet, and eat no more than 6 grams of salt per day; drink more warm water, and the daily amount of water should reach more than 2,000 ml, which can dilute the blood, reduce blood viscosity, and reduce the risk of cardiovascular and cerebrovascular diseases. . Maintain regular work and rest and adequate sleep, do not abuse drugs, and actively control various indicators such as blood pressure, blood lipids, body weight, uric acid, and blood sugar.


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