免疫力下降英文翻译（如何提高身体免疫力）

Your first line of defense is to choose a healthy lifestyle. Following general good-health guidelines is the single best step you can take toward naturally keeping your immune system strong and healthy. Every part of your body, including your immune system, functions better when protected from environmental assaults and bolstered by healthy-living strategies such as these:

你的第一道防线是选择健康的生活方式。遵循一般的健康指导方针，你可以采取自然的方式保持你的免疫系统强大和健康，这是最佳步骤。你身体的每一部分，包括你的免疫系统，在免受环境攻击和健康生活策略的支持下，都能更好地发挥作用，例如：

1. Don't smoke. 不要吸烟。
2. Eat a diet high in fruits and vegetables. 多吃水果和蔬菜。
3. Exercise regularly. 定期锻炼。
4. Maintain a healthy weight. 保持健康体重。
5. If you drink alcohol, drink only in moderation. 如果你喝酒，只能适量饮酒。
6. Get adequate sleep. 充足睡眠。
7. Take steps to avoid infection, such as washing your hands frequently and cooking meats thoroughly. 采取措施避免感染，例如勤洗手和彻底将肉煮熟。
8. Try to minimize stress. 尽量减少压力。

Many products on store shelves claim to boost or support immunity. But the concept of boosting immunity actually makes little sense scientifically. In fact, boosting the number of cells in your body — immune cells or others — is not necessarily a good thing. For example, athletes who engage in "blood doping" — pumping blood into their systems to boost their number of blood cells and enhance their performance — run the risk of strokes.

商店货架上的许多产品都声称能增强或支持免疫力。但提高免疫力的概念实际上在科学上没有什么意义。事实上，增加你体内的细胞数量——免疫细胞或其他细胞——并不一定是件好事。例如，运动员如果使用“血液兴奋剂”，即将血液注入血液系统以增加血细胞数量并提高其表现，就会有中风的风险。

Attempting to boost the cells of your immune system is especially complicated because there are so many different kinds of cells in the immune system that respond to so many different microbes in so many ways. Which cells should you boost, and to what number? So far, scientists do not know the answer. What is known is that the body is continually generating immune cells. Certainly it produces many more lymphocytes than it can possibly use. The extra cells remove themselves through a natural process of cell death called apoptosis — some before they see any action, some after the battle is won. No one knows how many cells or what the best mix of cells the immune system needs to function at its optimum level.

试图增强你的免疫系统的细胞是特别复杂的，因为免疫系统中有很多不同种类的细胞，对许多的微生物有不同的反应。你应该增加哪些细胞，增加到多少？到目前为止，科学家还不知道答案。众所周知的是，人体不断产生免疫细胞。当然，它产生的淋巴细胞比它可能使用的多得多。这些额外的细胞通过一种称为细胞凋亡的自然细胞死亡过程自我清除，有些在他们看到任何行动之前，有些在战斗胜利之后。没有人知道免疫系统需要多少细胞或是什么样的细胞组合才能达到最佳水平。

Like any fighting force, the immune system army marches on its stomach. Healthy immune system warriors need good, regular nourishment. Scientists have long recognized that people who live in poverty and are malnourished are more vulnerable to infectious diseases. Whether the increased rate of disease is caused by malnutrition's effect on the immune system, however, is not certain. There are still relatively few studies of the effects of nutrition on the immune system of humans, and even fewer studies that tie the effects of nutrition directly to the development (versus the treatment) of diseases.

就像任何一支战斗部队一样，免疫系统军队都是趴着行进的。健康的免疫系统战士需要良好的、定期的营养。科学家早就认识到，生活贫困、营养不良的人更容易感染传染病。然而，疾病发病率的增加是否是营养不良对免疫系统的影响造成的，尚不确定。关于营养对人体免疫系统影响的研究仍然相对较少，而将营养的影响直接与疾病的发展（与治疗）联系起来的研究则更少。

There is some evidence that various micronutrient deficiencies — for example, deficiencies of zinc, selenium, iron, copper, folic acid, and vitamins A, B6, C, and E — alter immune responses in animals, as measured in the test tube. However, the impact of these immune system changes on the health of animals is less clear, and the effect of similar deficiencies on the human immune response has yet to be assessed.

有一些证据表明，各种微量营养素缺乏——例如，锌、硒、铁、铜、叶酸和维生素A、B6、C和E的缺乏——改变了动物的免疫反应，如试管中所测量的。然而，这些免疫系统变化对动物健康的影响尚不清楚，类似缺陷对人类免疫反应的影响尚待评估。

So what can you do? If you suspect your diet is not providing you with all your micronutrient needs — maybe, for instance, you don't like vegetables — taking a daily multivitamin and mineral supplement may bring other health benefits, beyond any possibly beneficial effects on the immune system. Taking megadoses of a single vitamin does not. More is not necessarily better.

你能做什么？如果你怀疑你的饮食不能满足你所有的微量营养素需求——比如说，你可能不喜欢蔬菜——每天补充多种维生素和矿物质可能会带来其他健康益处，除了对免疫系统可能产生的有益影响之外。服用大剂量的单一维生素对健康不会有益处。更多未必更好。