How much do you know about the crooked blue-green "little earthworm" on the back of your hand?

I recently read about the psychology of colors that suppress appetite, which has rekindled my passion for losing weight. However, simply controlling food intake is not a long-term solution. It is best to supplement it with some exercise.

Then I remembered the gym card that was forgotten in the corner, and followed the address on it to find the gym I hadn’t been to for a long time. At present, the domestic epidemic has been basically controlled, and there are still many people coming to the gym to exercise.

Since I'm already in the gym, taking some photos is a must. However, when I was holding the dumbbells and taking photos in front of the mirror, I found that what was noticeable was not the muscle lines that lasted for just one second, but the blue veins on the back of my hands.

When I put down the dumbbells for a while, I raised my hand to look at my arm again, but I could only vaguely make out a few blue-green "little earthworms". The blue veins that had just been raised on the back of my hand had disappeared.

Although this is a very normal phenomenon, for me who is engaged in science, things are not that simple. So I quickly posted a photo of myself on WeChat Moments and then went home to do my old job.

Blue veins are particularly obvious on some people's hands and can appear with a little force. This is usually due to a thin body.

Some people have thicker subcutaneous fat (yes, I'm talking about fat people), so the blue veins are harder to see.

If the nurse is asked to choose, she will definitely prefer the first type of person, because when hanging an IV or drawing blood, it is necessary to puncture a vein, and it is easier to puncture a patient with obvious veins. On the other hand, for people with vague or invisible veins, the nurse may have to rely on her feeling...

Generally speaking, "blue veins" actually refer to the superficial veins under our skin. The reason why these blood vessels appear "cyan" or "blue" is that when light penetrates the skin and shines on the blood vessels, the red light will be "trapped" by the blood inside, and the blood vessel walls and even the skin will reflect the blue light back . Also, this has nothing to do with skin color.

In addition, when our blood flows under the compression of the heart, it will first pass through the lungs to combine with oxygen, and then be transported to the capillaries throughout the body through the arteries. When the oxygen in the blood is exhausted, the blood will turn dark red (the oxygen content is very low).

At this time, the veins in the body begin to search the capillaries for blood rich in carbon dioxide, and then return the blood to the heart, completing the body's complete blood circulation .

At this time, if we block their return route, we will see the "blue veins" on the surface of the body bulging.

Students who have donated blood will know that this phenomenon is caused by the semilunar venous valves on the veins that open toward the proximal end. The valves will open in the direction of the blood , but when the veins are blocked, the blood cannot flow back smoothly, and due to the existence of the venous valves, the blood cannot flow in the reverse direction, which eventually leads to "traffic jams" in the blood vessels.

However, there are more ways to make veins bulge, just like the blue veins on the arms when lifting dumbbells mentioned at the beginning of the article. Generally, men who exercise regularly will gradually break down the fat tissue in their body, and the blue veins under the fat will become more obvious. In addition, they need a lot of blood supply during strenuous exercise, so the blood supply to the arms increases, making the veins bulge .

So will bulging blue veins cause harm to the body? In traditional medicine, bulging blue veins may be a sign of blood stasis. However, with the development of modern medicine, it is now believed that most of the veins visible on the body surface are normal, and bulging blue veins are not in a pathological state, but rather a sign of good vascular function.

However, if veins appear raised, twisted, or even discolored in areas such as the neck or lower limbs, it is a cause for concern.

The appearance of blue veins on the neck is medically known as jugular vein distention . The jugular vein is a pressure gauge for the right atrium, which can reflect changes in right atrial pressure and volume. Abnormal conditions are generally caused by poor blood return or right heart failure caused by heart function.

The most common simple varicose veins in the lower limbs are those in which the surface blood vessels are varicose like earthworms and protrude very obviously from the skin, with the varicose veins forming clumps or nodules .

If this situation is not treated in time, it may also cause symptoms such as thrombophlebitis, lower limb ulcers and eczema, which is commonly known as "old leg rot".

In short, obvious or protruding blue veins do not mean there is something wrong with the body, but if the blue veins become tortuous and deformed, or if they suddenly appear when they were not there before, it indicates that there is a problem with the body's blood flow and needs to be taken seriously.