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Written by Seven Kings
During the Spring Festival, everyone is estimated to eat less meat, and after the festival, we should eat more fruits and vegetables. In addition to eliminating greasiness, fruits and vegetables have another unexpected benefit: prevent old scars on your body, such as acne scars, from cracking.
It's all because fruits and vegetables are rich in vitamin C.
Fresh fruits and vegetables are a major source of vitamin C because vitamin C is sensitive to heat and cooked dishes are low in vitamin C. Image source: wikipedia
Most primary and secondary school students know that vitamin C is a good medicine to deal with scurvy, scurvy is also caused by vitamin C deficiency, and vitamin C is mainly present in fresh vegetables and fruits, and many sailors died of scurvy in the age of great navigation. But what exactly is scurvy?
In fact, one of the major symptoms of scurvy is that the old wounds of the past have been re-cracked, and the whole person has begun to literally "split": the old wounds (such as the fracture healing place) will re-crack, the hair follicles will bleed, and the gums will bleed and even blacken.
Image credit: pixabay
This is because the human body cannot synthesize collagen in the absence of vitamin C, and collagen is equivalent to human glue, which can glue tissues and cells together.
However, this human body glue does not last forever, collagen will gradually decompose, compared with wounds that do not heal, the collagen of the scar is decomposed and synthesized faster, so the old scar needs to be updated and maintained frequently.
Normally, the body can replace the broken collagen with new collagen. But in the absence of vitamin C, the old and new alternately unbalanced, at which point the person cracks.
Symptoms of scurvy include bone pain, bleeding gums, fibrosis of hair follicle bleeding, easy injury, and poor wound healing. Image credit: ADMIRALTY LIBRARY, NAVAL HISTORIC BRANCH
The ancients have long known that sailors will crack again during long-term travel without eating fresh fruits and vegetables.
In fact, the English scurvy for scurvy comes from the German schorbuk, and the word is used to describe a common phenomenon that occurred in sailors who sailed for a long time in the 15th and 18th centuries - chest and abdomen cracking.
For example, British Royal Navy Admiral George Anson wrote in his voyage diary: "[Scurvy] is a disease that causes the belly to crack." ... Old scars from many years ago will crack again. ”
Anson is so aware of the symptoms of scurvy because he has witnessed the tragic situation of a large number of teammates. Upon his return from a four-year sailing adventure (1744), only 188 men remained behind his fleet of 1,854 men, most of whom died of scurvy.
Why doesn't the stomach crack when you can't eat fresh vegetables and fruits? This is because there is a lot of collagen in the bones of the human chest and abdomen - rib cartilage is made of collagen. No wonder the chest and abdomen become brittle when vitamin C is lacking.
Rib cartilage (red) is made up of collagen. Image source: wikipedia
Of course, old wounds and soft ribs are only one aspect, and there are many places where the body needs collagen, such as blood vessels.
When a blood vessel ruptures due to a lack of collagen, the blood flows to where it shouldn't go. For example, after the blood vessels in the brain rupture, the patient may have a stroke at any time.
And because vitamin C is involved in the synthesis of hair, hair will also fall out when vitamin C is lacking, or curled special-shaped hair will grow.
Typical symptoms of scurvy are fibrosis of hair follicles on the legs and buttocks, the appearance of curly hairs similar to corkscrews, and bleeding from hair follicles (reddish-brown dots in the picture). Image credit: doi.org/10.1016/S0190-9622 (99) 70244-6
In addition, vitamin C can also bind to free radicals with strong oxidation effects. If vitamin C is lacking, free radicals can damage neurons, causing communication problems between neurons. So in the case of long-term lack of vitamin C, people will also have terrible hallucinations.
Thomas Willis, a researcher of the history of the Great Voyages of the 17th century and an early member of the Royal Society, points out that many admirals suffering from scurvy at that time were crying because the food they fantasized about was not there.
Processed foods have very little vitamin C content. Image source: wikipedia
However, the causal relationship between vitamin C and cracking of old scars was not confirmed by modern research until the time of World War II.
During World War II, in order to determine the minimum vitamin C demand in the case of limited food, the British government did a vitamin C deprivation experiment called shipwreck (shipwreck).
The study was later called the MRC experiment because it was led by the Uk's Medical Research Council (MRC). In fact, the World Health Organization (WHO) is citing this study when it describes the symptoms of "old wound cracking" in scurvy.
The MRC experiment began in October 1944 and ended in February 1946 with 20 volunteers and the future Nobel laureate biologist Hans Adolf Krebs presiding over the experiment.
The experiment participants' recipe was an emergency food that did not contain vitamin C on a British Navy lifeboat. Outside of a fixed diet, participants were divided into three groups, with the first group not receiving any vitamin C supplementation, the second group receiving 10 mg of vitamin C supplementation per person per day, and the third group receiving 70 mg. These people have lived for 9 months without fresh vegetables and fruits.
To study the effects of vitamin C deficiency, the participants were also artificially scarred. The researchers created wounds on the thighs of the participants that were 1 centimeter wide and 1 centimeter deep to simulate being stabbed by a knife. Others had a 3-centimeter-long wound on their thigh and stitched with three stitches.
After 21 days, the researchers measured the force needed to re-open the wound as an indicator of the minimum daily vitamin C requirement. In fact, the rupture of old scars has also become a signal of termination of the MRC study.
The study found that for every 10 mg increase in vitamin C intake per day, the strength of the scar increased by 1 Newton. Therefore, the experiment concluded that the human body needs at least 10 mg of vitamin C per day; if the intake of vitamin C is insufficient, the wound will not heal for a long time. The World Health Organization notes that the difficulty of wound healing is one of the "early consequences" of vitamin C deficiency.
In 1747, James Lind, a military physician in the British Navy, demonstrated through controlled experiments that citrus fruits could treat scurvy. Image source: INSTITUTE OF NAVAL MEDICINE
Of course, these participants re-ingested vitamin C after 9 months of being deprived of vitamin C, and their changes were also the subject of research.
In the process of re-supplementing with vitamin C, this classic study also found that recovery from vitamin C deprivation takes a long time, and that the recovery period requires a large amount of vitamin C.
Specifically, even with a daily intake of 90 mg of vitamin C (recommended by the World Health Organization) for 6 months, the mechanical strength of the old scars of participants who had experienced complete deprivation did not return to normal levels.
In fact, there are similar reactions in other animals that cannot synthesize vitamin C on their own.
Guinea pigs, like humans, are unable to synthesize vitamin C.
Guinea pigs, like humans, are unable to synthesize vitamin C. A 1953 study published in proceedings of the Society for Experimental Biology and Medicine found that if a guinea pig whose wound on the belly had been healed for 6 weeks was given a vitamin C-deficient diet, after 26 days, the old wound of the guinea pig would crack and bleed.
After the MRC study in 1944, no longer studies of vitamin C deprivation of similar lengths appeared. However, some later vitamin C deprivation experiments found that it only takes more than 1 month to consume insufficient vitamin C, and the human body will have various conditions.
Manifestations of chronic vitamin C intake. Image source: wikimedia
In the 1960s, the Iowa State Penitentiary did research on short-term vitamin C deprivation.
The study found that after 45-52 days of deprivation of vitamin C, the hair follicles began to bleed and the gums were red and swollen and bleeding; by 60-80 days, the hair follicles at the ends of the buttocks and limbs began to keratinize and feel bad to the touch; after 84-97 days, symptoms such as joint edema and tooth loss began to appear.
The 22-year-old woman suffered from a chronic lack of vitamin C due to anorexia, and she eventually developed scurvy manifestations of atrophic gums and congestion and swollen lower limbs. Image source: dx.doi.org/10.1136/bcr-2017-223686
In fact, the "stock" of vitamin C in the human body is about 1500 mg, and irregular vitamin C intake for 8-12 weeks will trigger symptoms of vitamin C deficiency (such as bleeding from mouth ulcers, purple spots of hair follicles, rough skin, body aches, and poor mood), and scurvy will occur when the stock is less than 350 mg.
In modern society, the incidence of scurvy is not high, but vitamin C deficiencies are more common.
For example, according to the National Health and Nutrition Survey (NHANES) in 2003-2004, 7% of Americans have insufficient vitamin C levels in plasma, compared with 13% at the third National Health and Nutrition Survey (1988-1994).
If you don't want to crack in the New Year, eat more fresh vegetables and fruits, otherwise you will see the true face of your body after removing the patch.
Humans are "cracked" and need to be replenished with "citrus" goods.
Cover source: pixabay
Resources:
https://docs.qq.com/doc/DVGtmQ0tycGtCUmtF
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