How does staying indoors affect your immune system?

Beijing time july 1 news, according tomedia reports, in the past two months, a considerable number of people around the world have had to stay indoors, only to buy necessities when they go out. While this reduces our exposure to the new coronavirus, it may have an undetectable effect on our immune system, making us more susceptible to other infections.

Humans have evolved on a planet that follows a 24-hour circadian cycle, and our bodies are used to being associated with sunlight. A clear example of vitamin D produced by the skin under moderate-wave ultraviolet light. Daily vitamin D is produced to help strengthen bones and teeth, and also affects immune cells.

Vitamin D allows macrophages in the lungs, the first front against respiratory infections, to secrete an antibacterial peptide that kills bacteria and viruses directly. Vitamin D also regulates the activity of other immune cells, such as B-cells and T-cells, which regulate long-term immune responses. People who lack vitamin D in their bodies are more likely to develop viral respiratory infections such as influenza.

Researchers are now looking at whether vitamin D supplements can alleviate some of the serious complications associated with neo-coronary pneumonia. Earlier this month, geriatrician Rose Kenny and colleagues at Trinity College Dublin published data showing that the people with the highest mortality rates in Europe, including Spain and Italy, also had the lowest levels of vitamin D. This may sound counterintuitive, because the two countries are always sunny. But the researchers believe that lifestyle changes have led to increased time people spend indoors, and that these may be the reason for low levels of vitamin D in the body, along with people in these countries who use sunscreen.

While there may be other factors that may explain the high mortality rates in these countries, Kenny said: “There is strong evidence that there is a link between vitamin D and the immune pathways associated with neo-coronary pneumonia, especially those associated with severe responses. “First, vitamin D appears to reduce levels of an inflammatory substance called leukocyte interleukin-6, which is associated with severe breathing problems in neo-coronary pneumonia. Vitamin D also alters the utilization rate of the ACE2 receptors used in lung cells to enter cells and cause infection, making it difficult for the virus to establish a “base” in the body.

While randomization control trials are needed to confirm this protective effect of vitamin D, Kenny noted that all adults should consider taking vitamin D supplements during the current outbreak. But as many countries begin to lift their bans, some experts are calling on people to increase their vitamin D levels by increasing the amount of time they spend outdoors, which can also bring us other benefits.

Millions of people are unable to exercise and synthesize vitamin D on their way to work or school, as usual.

While there is no scientific evidence that regular exercise reduces the risk of contracting new coronary pneumonia, several studies have shown that exercise boosts our immunity to other viral infections, such as influenza and the common cold, and also enhances the body’s immune response to vaccines.

One explanation for this is that exercise helps relieve stress. “We know that people use exercise as a decompression method, and long-term stress is clearly bad for the immune system. Neil Walsh, who studies the effects of exercise on the immune system at John Moores University in the UK, says, “So if you can reduce stress levels through exercise, it will have a positive impact on health.” “

And if you have the conditions to move in parks, forests or other green spaces, it’s even better. Several studies have found that being in nature, even in a city park, can lower heart rate and blood pressure and regulate the secretion of the “stress hormone” cortisol. Long-term living in the vicinity of nature and often in the natural environment, more associated with cardiovascular disease, type 2 diabetes and reduced risk of early death.

In addition, a variety of theories have been put forward to explain these findings. One theory is that outdoor activities can increase our exposure to others and help us cope with stress and loneliness. Then there’s the “attention-recovery theory”, which holds that nature and sports inadvertently attract our attention and provide a chance for our overstretched brains to rest and recover.

However, trees may have a more direct effect on our immune system. Several studies have shown that spending a few days in the forest can increase the number and vitality of natural killer cells in the blood that can help the body detect and kill viruses and cancer cells. Japanese scientists suggest that inhaling plant-released bactericides may also be a positive factor. Studies have shown that these fungicides can affect cell activity when human natural killer cells are cultured in vitro. However, further research is needed to prove that inhaling fungicides can have a similar effect.

“I think these mechanisms are synergistic in practice,” says Catherine Ward-Thompson, director of the OPENSpace Research Centre at the University of Edinburgh. And mental relaxation, stress reduction and other psychological effects may be easier to obtain. “

How does staying indoors affect your immune system?

Outdoor activities can also improve the quality of our sleep. Closing the city behind closed doors may affect our circadian rhythms. This rhythm is produced inside the body and lasts about 24 hours and is associated with a variety of biological processes, including sleep. When we are outdoors, sunlight hits a series of light-sensitive cells at the bottom of the eye, which in turn communicate with a tissue in the brain called the visual cross- nucleus, keeping our circadian rhythms in sync with the time of day.

Many people have come up with a variety of fitness methods because of the outbreak. But outdoor activities can offer other benefits.

“Indoor light is often too dark to achieve this process. So if someone stays behind closed doors all week, circadian rhythms can be disrupted, leading to sleep disorders. Mariana Figueroa of the Light Research Center in New York points out. Her research shows that office white-collar workers who receive more bright light in the morning, such as walking to work, are more likely to fall asleep at night.

“Circadian rhythm disruption is associated with lack of sleep and weakened immune system response. “So, while light may not have a direct impact on immune function, it indirectly affects immune function through the regulation of circadian rhythms and sleep,” Figuero said. “Being exposed to bright sunlight in the morning can also have a positive impact on mood or help avoid depression.

It’s hard to say how long it takes to stay outdoors to feel the benefits. While morning light is especially important for regulating circadian rhythms, vitamin D synthesis is the highest at noon, as the mid-wave UV rays in the sun peak at noon.

Therefore, as long as conditions allow, everyone should be in keeping a social distance and do a good job of sun protection, under the premise, try to go out at least once a day. Sunlight and nature are the best therapists. (Leaf)