Strengthen Your Immune System
One aspect of the Covid-19 pandemic that has kept us guessing since the early days is why some people who get the virus don’t suffer much and others become desperately ill. What factors give some people a stronger immune system than others, regardless of age?
We know that our immune systems slowly decline as we age. The difference in rate of decline between individuals is one of science’s big mysteries. The immune system is complex, but most of us understand the basics: Our bodies detect an intruder（入侵者）– a virus or bacterium, and produce white blood cells to combat the problem.
No one knows why our bodies don’t produce as many immune cells as we get older. Researchers got some insights, especially regarding T cells, which are white blood cells that attack viruses. We possess two broad categories of T cells: “memory” cells that have encountered a certain pathogen（衣原体）and “remember” how to fight it. The other is “naïve” cells, which have yet to fight anything. As we age, it seems that the number of naïve T cells decreases.
And those are exactly the cells needed to recognize newly emerging microorganisms like the Covid-19 virus. This means that when that virus – something our immune systems haven’t seen before – shows up, most of us don’t have memory T cells to use, so the naïve cells have to take on the fight. Since older folks have fewer naïve cells to fight with, as a group they are more vulnerable.
The reasons why these key cells decline over time could be various and genetics plays a part. But it’s debatable how big a part compared with environment and lifestyle.
Chronic low-grade inflammation (炎症) that develops with advanced age can also affect the immune system. Lifestyle factors—poor sleep, ongoing stress, and weight gain – are common causes, as are systemic issues such as autoimmune diseases and decreased liver or kidney function. This inflammation causes the immune system to operate abnormally, which accelerates the aging process and can cause many other diseases.
While you can’t do anything about your genetic makeup, slowing it down can mean a higher immune reserve when you need it most. Fortunately, many factors that positively affect your immune system are within your control, including regular workouts and eating properly. Regular workouts boost immune function and lower inflammation. Exercises strengthen the body and may be the most important lifestyle intervention (干预) you can add. Eating right and avoiding obesity, whose inflammatory effect is deadly, are common sense.
Besides, research has shown that stress can speed immune senescence (衰老). Self-care in this area is critical, from anti-stress activities to asking for help in unresolved stressful situations.
The pandemic has changed people’s lives and it will lead to a new era in immunity research. If we can do a wider search rather than chase after individual diseases, we will handle all immune challenges better.
【小题1】How does the immune system work?【小题2】Why are the old considered more vulnerable?
【小题3】Paraphrase the underlined sentence “But it’s debatable how big a part compared with environment and lifestyle.”
【小题4】Explain how the Covid-19 pandemic has changed your lifestyle. (about 40 words)
