Read the following passage. Summarize the main idea and the main points of the passage in no more than 60 words. Use your own words as far as possible.

Take care of your spine (脊柱)

    The spine stands at the center of your health, providing your body with structure and support. It also contains your spinal cord, a massive collection of nerves conveying electric signals from the rest of your body to your brain. Since your spine is so central to health, it's important to look after it.

Maintain good posture (姿势)is one of the most important things you can do to keep you spine healthy. Proper posture means standing or sitting while keeping your spine straight, except for its natural curves. Posture comes into play even when you're asleep. Sleeping on your side puts less stress on your spine than most other positions. Staying still for too long—even if your posture is good—can be hard on your back. Especially if you look at a desk most of the day, it's important to get up and stretch periodically.

    Exercise is also an important factor in the health of your spine. Stretches can help the muscles around your spine relax and allow bones to shift into better arrangement. Strength exercises like pushups can also help by strengthening the muscles around your spine. However, don't overdo the exercise, as repeated motions can strain the muscles around your spine.

    Finally, your diet affects the health of your spine because many vitamins are necessary for bones and nerves. In particular, B vitamins and omega-3 fatty acids keep nerves healthy, so you may want to consider taking a supplement. Another important factor is vitamin D, which is essential for strong bones. Vitamin D can come from some foods, but it's also absorbed from sunlight, so it may help to do some of those back exercises outside.

    Many of the actions necessary to keep your spine healthy are identical to those need to preserve your health in other ways. So protect our back, and the rest of body will benefit.