阳光是天然的免疫增强剂

Sunlight Is a Natural Immune Booster

 

　

By. Joseph Mercola

　

最近，乔治敦大学医学中心(GUMC)的研究人员发表了一项在培养皿中使用细胞的实验室研究，显示暴露在蓝色和紫外线(UV)下会增加T细胞的活性——参与免疫功能和抵抗感染的白细胞。
 
这被认为是第一个表明光对这种特殊类型的免疫细胞有影响的研究，因此需要更多的研究来验证结果。然而，医学文献中有大量的证据证实阳光具有增强免疫功能。
 
在这项研究中，光被发现可以刺激过氧化氢(H2O2)的产生，从而提高T淋巴细胞的活性。只需5到10分钟的阳光照射就可以增强免疫细胞的活性。正如一篇新闻报道所指出的:
 
研究人员表示，由于人类皮肤的表面积很大，皮肤中存在的所有T细胞都可能通过暴露在蓝光下而受益。
 
需要注意的是，维生素D只能通过暴露于UVB而在体内产生，而UVB在长时间的阳光照射下是有害的。
 
研究人员得出结论，如果太阳光中的蓝光能够激活抗感染T细胞，那么对于许多患者来说，这可能是一种提高免疫力的潜在治疗手段。
 
尽管研究人员似乎对蓝光本身可能是一种有价值的免疫增强疗法抱有希望，但重要的是要认识到光的生物效应可能非常复杂，正确地利用蓝光也很重要。
 
亚历山大·温斯迟博士解释说,世界一流的光生物学专家,过度暴露于蓝色的光——比如,从LED照明,主要是蓝色和缺乏阳光和中近红外白炽灯照明——是非常有害的,而且可能是龄相关性黄斑变性(AMD)一个重要的危险因素年。
 
最健康的蓝光来自太阳，因为它被近红外辐射平衡，这有许多重要的生物功能。重要的是，近红外辐射会激活线粒体中的细胞色素C氧化酶，帮助优化ATP的生产。
 
合理的晒太阳对健康有很多好处。很多都是维生素D产生的结果，当你的皮肤暴露在紫外线UV B下时就会产生维生素D，但还有很多与维生素D无关
 
最近的研究表明，蓝光和UVA都能增强T淋巴细胞的活性。只需5到10分钟的阳光照射就可以增强免疫细胞的活性
 

 
T细胞本质上是感光的
 
在很长一段时间里，人们认为哺乳动物只有眼睛里有光敏细胞。我们现在在人体的许多其他部位发现光敏细胞。
 
正如作者所指出的，这项研究表明“T淋巴细胞具有内在的光敏性，这种特性可能会增强它们在皮肤上的运动能力。”换句话说，T细胞能感知光线并对光线做出反应。
 
蓝光会在T细胞中引发过氧化氢(H2O2)的产生，从而引发化学级联反应，从而增加T细胞的活力。运动能力或活性的增强反过来又能让免疫细胞更好地工作。
 
有趣的是，一旦T细胞被激活，它们也会改变自己的抗氧化能力——这种效应似乎允许在光照下产生更多的H2O2。
 
T细胞的光谱敏感性在紫外A (UVA)范围的~350纳米(nm)和蓝色光谱的~470纳米(nm)达到峰值。后者(470 nm光)以前曾被证明可以在体外杀死耐甲氧西林金黄色葡萄球菌(MRSA)。
 
降低高血压，降低患心脏病和癌症的风险
 
研究表明，当阳光照射到皮肤上时，一氧化氮(NO)会释放到血液中。NO是一种能有效降低血压的化合物，有助于保护心血管系统，降低心脏病和中风的风险。
 
UVB通过扩张血管，特别是扩张皮肤中的毛细血管来降低血压。这将引导你60%的血液流向那里。这样，阳光就能轻易地穿透你的血液。
 
阳光具有紫外线杀菌作用，有助于杀死血液中的感染。在19世纪末和20世纪初，这种阳光被用来治疗肺结核，甚至在1903年，芬森也因此获得了诺贝尔奖。
 
根据2013年的一项研究，每一个死于皮肤癌的人，就有80人死于与高血压有关的中风或心脏病。因此，死于心脏病或中风的风险比死于皮肤癌的风险平均高出80倍。
 
而较高的维生素D水平与l有关

　

Most recently, researchers at Georgetown University Medical Center (GUMC) published a laboratory study using cells in petri dishes, showing that exposure to blue and ultraviolet (UV) light increases T cell activity — white blood cells involved in immune function and fighting infections.

 

This is thought to be the first study showing an impact of light on this particular type of immune cell, so more research is needed to verify the results. However, there's plenty of evidence in the medical literature confirming that sunlight has immune-boosting properties.

 

In this study, light was found to stimulate the production of hydrogen peroxide, which boosted the activity of T lymphocytes. As little as five to 10 minutes of sun exposure were needed to boost immune cell activity. As noted in one news report:

 

"Given the large surface area of human skin, all of the T cells present in skin could potentially benefit from this phenomenon through exposure to blue light, the researchers suggest.

 

Note that vitamin D is only produced in the body via exposure to UVB rays, which can be harmful in cases of prolonged sun exposure.

 

If blue light from the sun's rays is capable of energizing infection-fighting T cells, it could be a potential means of treatment for boosting immunity in many patients, the researchers conclude."

 

While the researchers appear hopeful that blue light alone might be a valuable immune-boosting treatment, it's important to realize that the biological effects of light can be very complex, and it's important to get it right.

 

As explained by Dr. Alexander Wunsch, a world class expert on photobiology, excessive exposure to blue light — such as that from LED lighting, which is primarily blue and devoid of near-infrared found in sunlight and incandescent lighting — can be quite harmful, and may be a significant risk factor for age-related macular degeneration (AMD).

 

The healthiest blue light is from the sun, as it is balanced by near-infrared radiation, which has many important biological functions. Importantly, near-infrared radiation will activate cytochrome C oxidase in your mitochondria and help to optimize ATP production.

 

Sensible sun exposure has many health benefits. Many are the result of vitamin D production, which occurs when your skin is exposed to UV light, but many others are unrelated to vitamin D

 

Recent research shows both blue light and UVA light boosts the activity of T lymphocytes. As little as five to 10 minutes of sun exposure was needed to boost immune cell activity

 

The healthiest blue light is from the sun, as it is balanced by near-infrared radiation, which activates cytochrome C oxidase in your mitochondria and helps optimize ATP production

 

T Cells Are Intrinsically Photosensitive

 

For a long time, it was believed mammals only had photosensitive cells in the eye. We're now finding photosensitive cells in many other areas of the human body.

 

As noted by the authors, this study demonstrates that "T lymphocytes possess intrinsic photosensitivity and this property may enhance their motility on skin." In other words, T cells sense and respond to light.

 

Blue light specifically triggers the production of hydrogen peroxide (H2O2) in T cells, which triggers a chemical cascade that results in increased T cell motility. The increased motility or activity, in turn, allows the immune cells to function better.

 

Interestingly, once the T cells are activated they also alter their antioxidant capacity — an effect that appears to allow for greater H2O2 production in response to light.

 

The spectral sensitivity of T cells peaked at both ~350 nanometers (nm), which is in the ultraviolet A (UVA) range, and ~470 nm, which is in the blue spectrum. The latter (470 nm light) has previously been shown to kill methicillin-resistant Staphylococcus aureus (MRSA) in vitro.

 

Lowering high blood pressure and reducing risk for heart disease and cancer

 

Research has shown that when sunlight strikes your skin, nitric oxide (NO) is released into your bloodstream.26 NO is a powerful blood pressure lowering compound that helps protect your cardiovascular system, cutting your risk for both heart attacks and stroke.

 

UVB light lowers blood pressure by dilating blood vessels specifically the capillaries in your skin. This directs about 60 percent of your blood flow there. This then allows the sun's rays to easily penetrate into your blood.

 

Sunlight has UV rays known to be germicidal and can help kill infections in your blood. This aspect of sunlight was used to treat tuberculosis in the late 19th and early 20th centuries, even awarding a Nobel prize to Finsen in 1903 for this work.

 

According to one 2013 study,27,28 for every single skin cancer death, 60 to 100 people die from stroke or heart disease related to hypertension. So your risk of dying from heart disease or stroke is on average 80 times greater than your risk of dying from skin cancer.

 

While higher vitamin D levels correlate with lower rates of cardiovascular disease, oral vitamin D supplements do not appear to benefit blood pressure, and the fact that supplements do not increase nitric oxide may be the reason for this.

 

Preventing infectious diseases

 

Both UV light itself and the vitamin D produced when your skin is exposed to it have potent antimicrobial effects.

 

While vitamin D increases production of naturally occurring antimicrobial peptides that destroy the cell walls of viruses and bacteria, UV light also increases blood levels of infection-destroying lymphocytes (white blood cells).

 

Besides boosting rates of cardiovascular disease, widespread sun avoidance may also be responsible for the reemergence of tuberculosis (TB), which now kills about 4,100 people every single day.

 

In 2014, there were 1.5 million TB-related deaths worldwide, making it the No. 1 infectious disease out there. Compare that to the 55,100 who die from melanoma each year (worldwide).

 

UV light, especially blue light, also acts as a potent disinfectant of your environment. Research has found UV light can reduce the spread of tuberculosis in hospital wards and waiting rooms by 70 percent, and helps kill 90 percent of drug-resistant bacteria in hospital rooms.

 

Data suggests UV light at 254 nm can kill drug-resistant strains of S. aureus and E. faecalis in as little as five seconds.

 

How Sun Exposure Improves Your Immune Function  https://articles.mercola.com/sites/articles/archive/2017/01/23/how-sun-exposure-improves-immune-function.aspx