3. Tooth Brushing 刷牙

Traditional wisdom is that we should brush twice a day, after meals. Well, actually, our obsessive-compulsive tooth-brushing practices lead to deteriorating oral health, including increased numbers of cavities and eventual tooth loss.
每天饭后刷牙？传统智慧不管用啦。其实每天的强迫性刷牙会损害口腔健康，造成蛀牙增多和牙齿脱落。

The reason is that the acidity in food and beverages causes tooth enamel to soften, and brushing right after eating an acidic meal strips enamel from the teeth, leaving them vulnerable to cavities. Leaving a little food behind actually doesn't cause as much damage as your toothbrush does as it scrubs the natural protective layer off the teeth.
食物和饮料中的酸性会造成牙齿釉质软化，马上刷牙容易得蛀牙。嘴里留点食物的害处绝对没有马上刷牙大。

So how the hell are we ment to do it?
那我们该怎么刷牙？

Studies show that flossing is much more important than brushing. Dental floss actually removes the bacteria that clump together between your teeth, without scrubbing and stripping layers off them.
用牙线清洁牙齿比刷牙要重要得多。牙线可以在不破坏牙齿保护层的情况下清理牙齿间堆积的细菌。

4. Sitting 坐着

Long periods of sitting increase your risk of diabetes, heart disease and even cancer, no matter how much you work out when you're not sitting. Sitting down for long periods of time means that you'll probably die earlier. This is all because of the invention of chairs.
长期保持坐姿会增加得糖尿病、心脏病和癌症的风险，甚至可能意味着早死。罪魁祸首是椅子的发明。

When you're sitting on a chair, our abdominal muscles relax, and suddenly your spine alone has to take the entire weight of your upper torso. The extra stress puts pressure on your spinal disks and can eventually lead to chronic back pain.
坐在椅子上，我们的腹部肌肉会放松，整个上半身的重要只能靠脊椎支撑。脊椎间盘上增加的压力会导致慢性背部疼痛。

So how the hell are we meant to do it?
那我们该怎么坐？

Some experts on sitting recommend "active sitting" using an exercise ball, kneeling stool or something else without a high back.
专家建议“积极坐姿”。不管健身球还是凳子，只要没有高靠背就好。

There's another option : lying back at a 135-degree angle with their feet on the floor. : A study used an MRI showed the least spinal disk movement in this position. So try it at work, and be brave to tell your boss you're avoiding future sick days.
还有另外一个选择：脚着地，身体135度仰卧，这样的姿势对脊椎间盘运动要求最少。试试这个姿势，记得告诉你老板，你是在保证将来的身体健康。