评论
打印
You might believe that drinking milk, with all its calcium and vitamin D, is the one thing you need for strong and healthy bones.
你可能相信，牛奶含有钙和维生素D，只要喝牛奶能让骨骼变得强壮、健康。
And it's a really nice message that sold a lot of milk over the years, but it's just not scientifically accurate.
这一点给牛奶增加了不少销量，但它从科学的角度来讲并不准确。
When we focus on milk, we lose the bigger picture of bone health. So let's start at the beginning.
在我们把注意力集中在牛奶上时，我们就失去了对骨骼健康大局的把握，那么我们从头开始吧。
Adults have 206 bones that form the main part of the skeletal system.
成年人有206块骨头，构成了骨骼系统的主要部分。
They're the support structure or cage that protects our organs, but they do so much more.
它们是保护我们器官的支撑结构或者说是支架，但它们的作用远不止这些。
They work with our muscles to move our bodies, they store important minerals, they produce hormones, and they even make our blood.
它们和我们的肌肉一起运动我们的身体，它们储存重要的矿物质，它们产生荷尔蒙，它们甚至制造了我们的血液。
Many people think of a Halloween skeleton when they imagine bone, but that only gives us a one-dimensional view. Bone actually has three layers.
很多人一想到骨头就会想到万圣节的骷髅，但那只是一维视角，骨头实际上有三层。
On the outside, there's the periosteum, a tough membrane that covers and protects.
外面是骨膜，一层负责覆盖和保护的坚硬的膜。
Next, there's a thick layer of compact bone, the white, hard, smooth part that most people are familiar with.
然后是一层厚厚的致密骨，就是大多数人都很熟悉的白色、坚硬、光滑的部分。
But inside, there is spongy or trabecular bone, and an inner core filled with bone marrow, which contains stem cells that make blood and are constantly dividing.
但内部还有海绵状骨或者说小梁骨，以及一个注满骨髓的内核，里面有造血和不断分裂的干细胞。
Most people understand that our bones grow when we're kids and adolescents. We reach our peak bone mass in our 20s.
大多数人都知道我们的骨骼是在儿童和青少年时期生长的，骨量在20多岁时达到峰值。
What many people don't know is even after we stop growing, we are constantly removing old bone and replacing it with new.
但很多人不知道的是，即便在我们的身体停止生长后，旧骨仍在不断被移除，然后被新骨替换掉。
One estimate is enough bone is removed and replaced that a new skeleton is made every 10 years.
据估计，每10年就会有足够的骨骼被移除和替换，从而形成新的骨骼。
After we reach our peak bone mass, bone removal starts to outpace replacement.
当我们的骨量达到峰值时，骨移除的速度开始超过骨置换的速度。
This can eventually affect the integrity of the bone and it lowers the bone mass or the amount of bone that we have.
这最终会影响到骨骼的完整性，骨骼的质量或者说骨骼的数量会降低。
The bone disease osteoporosis is an extreme version of this process.
骨质疏松症是这一过程的极端版本。
Bone loss outpaces replacement, and combined with other changes, this can lead to so much fragility that even small bumps or falls can create fractures.
骨质流失的速度超过了骨质置换的速度，再加上其他变化，可能会导致骨质非常脆弱，即便是很小的碰撞或跌倒也有可能造成骨折。
Another cool fact about bones is they store calcium, so if intake is low, meaning not enough in our diet, the body draws calcium from the bone.
另一个关于骨骼的很酷的事实是，它们会储存钙，所以如果摄入量低，就是说我们的饮食中钙的摄入不足，身体就会从骨骼中吸收钙。
This can also contribute to bone loss, so we need enough dietary calcium to maintain our bone.
这也会导致骨质流失，所以我们需要足够的膳食钙来维持骨骼。
Vitamin D fits into the picture because it helps our body absorb calcium.
其中就有维生素D，因为它能够帮助我们的身体吸收钙。
When we think of calcium and vitamin D, many of us picture a frosty glass of milk.
当我们想到钙和维生素D时，很多人会联想到一杯冰冻牛奶。
Milk is not the only good source of calcium out there.
牛奶并不是钙唯一的比较好的来源。
Humans are creative omnivores.
人类是创造性的杂食者。
We can get calcium from a lot of other sources -- yogurt and cheese, for example -- but also look for leafy greens like spinach and kale, cruciferous vegetables like broccoli and cabbage, and proteins like tofu, nuts, beans, eggs and fish.
我们可以从很多其他来源获得钙，例如酸奶和奶酪；也可以吃绿叶蔬菜，如菠菜和甘蓝；十字花科蔬菜，如花椰菜和卷心菜；蛋白质，如豆腐、坚果、豆类、鸡蛋和鱼。
Fortified cereals and orange juice are also good too, and chia seeds.
强化谷物和橙汁也是不错的选择，还有奇亚籽。
And vitamin D is plentiful in fatty fishes, and our skin makes it from the sun. However, some people may need supplements.
脂肪丰富的鱼类富含维生素D，我们的皮肤也会从阳光中获取维生素D，但可能还是有些人需要补充维生素D。
Another important factor for bone health is exercise.
另一个影响骨骼健康的重要因素是锻炼。
Mechanical loading stimulates the cells that build bone and muscles pulling on the bone may do this as well.
机械负荷会刺激骨骼细胞，肌肉对骨骼的拉动也会起到同样的作用。
In fact, any activity that puts stress on your bones, like walking, jogging, dancing, racket sports, even strength training like doing weights, stimulates extra deposits of calcium and growth of new bone.
事实上，任何对骨骼造成压力的活动，比如散步、慢跑、跳舞、球拍运动，甚至像举重这样的力量训练，都会刺激额外的钙沉积和新骨骼的生长。
In addition, stronger muscles can help with balance.
此外，强壮的肌肉可以帮助身体的平衡。
And one of the best ways to prevent a hip fracture? Reducing falls with better balance.
预防髋部骨折最好的方法是什么呢？用更好的平衡感来减少跌倒。
If milk is your thing, that's completely OK, but don't forget that bone health is so much more than just milk.
如果你喜欢喝牛奶，完全没问题，但不要忘记，骨骼健康不是只有牛奶可以维持。
