如何减少胆固醇氧化
本视频由Michael Greger医生于 2018 年 6 月 1 日发布，来自NutritionFacts.org — 能救命的营养学。
Michael Greger 医生是畅销书《How Not to Die》作者，中文译本：繁体版书名为《食疗圣经》。简体版书名为《救命》，于今年5月底出版。
编者前言：
本视频与 “氧化胆固醇导致阿尔茨海默病” 是姊妹篇。
“如何减少胆固醇氧化”
“How to Reduce Cholesterol Oxidation”
摘要：加工食品中的鸡肉，鱼肉和鸡蛋粉会产生更大的胆固醇氧化副产物风险，但可以采取一些措施减少胆固醇氧化。
Chicken, fish, and egg powder in processed foods present greater risk from cholesterol oxidation byproducts, but there are things you can do to reduce exposure.
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大量证据表明氧化型胆固醇可能是阿尔茨海默病的主要诱因之一。但还没完呢。
“A significant body of evidence indicates that oxidized cholesterol may be one of the main triggers of Alzheimer’s disease.” But, that’s not all.
胆固醇氧化产物与多种重大慢性疾病的发生和发展有关，包括心脏病、糖尿病和肾衰竭。
Cholesterol oxidation products “are associated with the initiation and progression of multiple major chronic diseases,” including heart disease, diabetes, and kidney failure.
而这些产物是在肉类产品加热时生产的。所有形式的烹饪都会导致这点，因为只需要摄氏150度左右就可以达到最大程度的胆固醇氧化。
And, they’re produced when animal products are heated. All forms of cooking can do it, since you can get “maximum cholesterol oxidation” at only about 300 degrees Fahrenheit.
但有没有相较之下更糟糕的烹饪方式？
But, is there some type of cooking that’s worse than others?
如果看看驹肉，也就是幼马肉，一般在微波时发现较高水平的氧化。
Well, if you look at foal meat, which is like baby horse meat, higher levels of oxidation in general were found in microwaved meat.
事实上，微波炉加热鸡肉或牛肉似乎会比油煎产生两倍多的胆固醇氧化。
And, indeed, microwaving chicken or beef appears to produce about twice as much cholesterol oxidation than frying.
再来看看培根，生培根里没有发现任何氧化的胆固醇。它像所有肉类产品一样具有胆固醇，但是直到煮熟，胆固醇才会被氧化。
Whereas, if you look at bacon, raw bacon wasn’t found to have any oxidized cholesterol. It has cholesterol, like all animal products, but it’s not oxidized until you cook it.
在首次烹调时，烧烤似乎是最安全的形式，但是当放回冰箱，稍后用相同的方式重新加热，胆固醇氧化会迅速飙升。
Grilling seems to be the safest the first time around, but then, when you put it back in the fridge and reheat it later using the same method, the oxidized cholesterol levels all shoot up.
不过这不仅仅是因为热气。虽然生肉的胆固醇氧化含量通常很低，在暴露于诸如光的促氧化剂之后浓度便倾向于显着增加。
It’s not just heat, though. Although levels in raw meats are usually low, “concentrations tend to increase dramatically after exposure to pro-oxidation agents, such as light.”
那到底要怎么办，爬进猪的身体里，从里面吃培根？
What are you supposed to do, crawl inside the pig and eat the bacon from the inside?
不，可以用红色塑料膜包裹肉。透明塑料包装似乎不起作用，但红色挡住一些光波，可以延缓胆固醇的氧化。
No, you could wrap the meat in red plastic wrap. Clear plastic wrap doesn’t seem to work, but the red blocks some of the light waves and can “delay cholesterol oxidation.”
这是针对马肉片。切片肉制品的问题更严重，因为更多的表面被暴露在空气和光线下。绞肉也有同样的问题，暴露面更多。
This was for “horse meat slices.” The problem is worse with “sliced meat products,” because more of the meat is exposed to air and light. Same problem with ground meat; it’s just so much more exposed.
除非把肉放在某种真空包装里，即使在黑暗的冰箱里，光有氧气暴露就可以暴涨氧化水平。或在冰柜里。
Unless you keep meat in some kind of vacuum pack, even in a dark refrigerator, the oxygen exposure alone can shoot up oxidation levels. Or, in the freezer.
的确，烹饪生鱼可以将水平从8提高到18，但经过几个月的冷冻，即便是生鱼，都有约十倍的增高，并持续上升。
Yeah, cooking raw fish can boost levels from 8 to 18, but after a few months, frozen fish - even raw - starts out about ten times higher and just goes up from there.
无论是微波或油炸，如果要说哪种肉最糟，鸡肉比牛肉差一倍。
And, in terms of which meat is the worst, microwaved or fried, chicken was twice as bad as beef.
其原因似乎与肌肉的多不饱和脂肪含量有关，顺序是鱼，家禽，猪肉，牛肉，羊肉。
The reason, it seems, has to do with the “polyunsaturated fat content of the muscle,” which goes fish, then poultry, then pork, then beef, then lamb.
所以白肉更容易胆固醇氧化。
So, white meat is more susceptible to cholesterol oxidation.
的确，红肉有更多的饱和脂肪，但鱼肉和鸡肉往往会累积更多的氧化胆固醇。
Yes, red meat has more saturated fat, but fish and chicken tend to build up more oxidized cholesterol.
所以和其他类型的肉相比，鸡肉和烤鲑鱼（三文鱼）已被证明会产生更多胆固醇氧化产物。
So, “chicken and roasted salmon have been shown to generate greater amounts of cholesterol oxidation products than other types of meat.”
令人惊讶的是，我们发现鲑鱼（三文鱼）中氧化胆固醇最高的增长是通过蒸，主要是因为暴露在热气更长的时间。每次烹饪过程后胆固醇氧化都会增加，但蒸却增加了胆固醇氧化1000％以上。（老玉米吃素前曾喜欢吃清蒸三文鱼
Surprisingly, though, “the highest increase of oxidized cholesterol in salmon was found through steaming, mainly just because it’s exposed to heat longer. Cholesterol oxidation “increased after each cooking procedure, but steaming increased the total amount by more than 1000%.”
不过，有两种方式可以让鸡肉比鱼肉更糟。
There are two ways chicken meat may pull ahead, though.
一个是如果首先喂养鸡一些腐臭脂肪。不幸的是，各种不合格的东西最终都会送到炼脂厂，来转变成动物饲料。
One is if you feed the chickens rancid fat in the first place. And, unfortunately, all sorts of substandard stuff ends up at the rendering plants to be turned into animal feed.
还有辐照。从传染病的角度来看，鸡肉会被照射以改善食品安全。但从慢性病的角度，照射反而可能会降低食品安全性。但这比死于沙门氏菌要好吧？
And also irradiation. When chicken meat is irradiated to improve its food safety from an infectious disease standpoint, it may diminish food safety from a chronic disease standpoint. But, hey, it’s better than dying from salmonella.
关于奶制品，在上一个视频中我谈到了酥油的潜在危险，这让我怀疑超高温灭菌牛奶，指的是超高温处理，来制作那些不需要冷藏的、半鲜奶油加半牛奶的咖啡奶精。这似乎提高了约50％的氧化胆固醇水平，比常规巴氏杀菌法更糟糕，但有趣的是，半山羊奶是比较安全一点的选择（如果找得到这种东西的话）。
In terms of dairy, in my last video, I talked about the potential dangers of ghee, which made me wonder about UHT milk, which stands for ultra-high temperature processing, to make little half-and-half no-refrigeration-needed coffee creamers. That does seem to boost oxidized cholesterol levels by about 50% — worse than just regular pasteurization, though, interestingly, if you can find goat milk half-and-half, that would be safer.
鸡蛋也有同样的问题。
Same problem with eggs.
加工食品中的蛋粉有助于延长其在货架上的寿命，但对人命来说可就不怎么好了。
Egg powder in processed foods is good for shelf life, but may not be so good for human life.
就像含有鸡蛋的包装食品一样，意大利面，许多烘焙食品，蛋黄酱。所以即使是不吃鸡蛋的人，如果购物时不读产品成份，可能仍然会无意中从加工食品吃到。（译注：所以买东西一定要看成份表，陷阱到处都有！）
So, that’s like packaged food with eggs in it, like pasta, many baked goods, mayonnaise. So, even people who stay away from egg eggs, may still be unwittingly exposed through processed foods, if they don’t read the label.
如果只是氧化的问题，那为什么不添加合成或天然抗氧化剂到动物产品本身？
If it’s all about oxidation, why not just add “synthetic or natural antioxidants” to the animal products themselves?
还真的有人试过，像把柠檬香蜂草茶加到汉堡肉饼呢？
They’ve certainly tried; like, what about adding lemon balm tea to hamburger patties?
无效，但这可能是因为不想影响味道，而加的量不够多。
It didn’t work, but that’s likely because they couldn’t add enough without affecting the taste.
加入樱桃怎么样？
What about adding cherries？
樱桃是红色的，混合在一起挺好的。还真的发生效用了！两种不同类型的酸樱桃显著减少胆固醇氧化，但把樱桃加在肉上，似乎有那么点怪。
They’re red，they would blend right in. And, it worked! Two different types of tart cherries significantly reduced the cholesterol oxidation, but meat with a cherry on top seems a little out of place.
那如果只是加大蒜和洋葱呢？
How about just good old garlic and onions?
这是普通猪排中的氧化胆固醇的量，通过加入洋葱和蒜明显减少。
Here’s the amount of oxidized cholesterol in a plain pork chop, significantly reduced by adding onion or garlic.
尽管有趣的是，鸡肉的胆固醇氧化是通过鼠尾草减少，而不是大蒜。事实上，大蒜甚至可能加速脂肪氧化。
Though, interestingly, in chicken, cholesterol oxidation was helped by sage, but not garlic. In fact, garlic may even accelerate fat oxidation.
所以，可以采取几种措施来减少食物中的胆固醇氧化：
So, “there are several measures that can be taken to reduce cholesterol oxidation in foods:
不用含有胆固醇脂肪的东西来烹调食物，如黄油或猪油，好降低食物中的总胆固醇含量；
Reducing the total cholesterol content in food by not cooking food with cholesterol-containing fat”, like butter or lard;
也许可以先喂动物抗氧化剂，或者之后再加进去；
Maybe we can “feed animals antioxidants before, or add them afterwards;
使用尽可能低温的烹饪方式;
Use as low a temperature to cook as possible;
使用不透明的真空包装之类的。
Use some kind of opaque vacuum packing or something.
但如果退后一步想，只有那些本来就含胆固醇的食物，可以到最后变成氧化胆固醇。
But, if you take a step back, only foods that start out with cholesterol can end up with oxidized cholesterol.
所以要减少食物中胆固醇氧化，最主要的方法可能是降低食物的总胆固醇含量，不仅仅是避免添加黄油，而是以全食物植物饮食为主，其本身不含任何胆固醇，也就不用考虑胆固醇氧化的问题了。
So, the primary method, in terms of reducing cholesterol oxidation in foods, may be to “reduce the total cholesterol content of the food” — not just by avoiding adding extra with butter, but instead, centering one’s diet around whole plant foods, which don’t have any cholesterol to get oxidized in the first place.
（翻译：Huiling Liu, 字幕制作及编辑：老玉米 Karen Chou)
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编者后记：
动物性食物均含有胆固醇。
我们的身体可以自己制造一切所需的胆固醇，不需要额外从其它动物那里摄取胆固醇。
胆固醇那么容易氧化，所以 Michael Greger 医生开玩笑说：“那到底要怎么办，爬进猪的身体里，从里面吃培根？”
Michael Greger 医生给出了解决方案：“以全食物植物饮食为主，其本身不含任何胆固醇，也就不用考虑胆固醇氧化的问题了。”
虽然我们应该活在当下，但也应该为将来的健康考虑，万一得了阿尔茨海默病或老年痴呆，那可不是闹着玩儿的！另外，还有文章开头所说的：心脏病、糖尿病和肾衰竭。
祝每个人健康快乐！
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