1 . Bad teeth may be painful and it’s getting worse without treatment. They can even ruin your life. Illness of the teeth can find its way into the blood system. This can increase the chances of a heart disease or other illnesses.

Experts say good care for teeth should start at birth. Mothers’ milk is the best food for the healthy development of teeth.

But dentists say a baby’s mouth and early teeth should be cleaned after each feeding. Use a cloth with a little warm water. Do the same if a baby is fed with a bottle. Experts say if you decide to put your baby to sleep with a bottle, give him only water.

When a baby’s teeth begin to appear, you can clean them with a wet toothbrush. Dentists say it is important to find soft toothbrushes made especially for babies and to use them very gently. Young children often eat toothpaste (牙膏) when they brush their teeth, so they should be carefully watched when they brush their teeth.

Parents often ask what effect thumb sucking (吮拇指) might have on their baby’s teeth. Experts generally agree that this is fine early in life. Most children stop sucking their thumbs by the age of four. If it continues, parents should talk to their children’s dentists or doctors.

Dentists say children should have their first dental visit by the time they are one year old. They say babies should be examined when their first teeth appear, usually at around six months.

4 . Eyesight plays an important part in our daily life. Every waking moment, the eyes are working to see the world around us. Over forty percent of Americans worry about losing eyesight, but it’s easy to include steps into our daily life to ensure healthy eyes. Here are some suggestions for a lifetime of healthy eyesight:

I. Schedule yearly exams.

    1    . Experts advise parents to bring babies 6 to 12 months of age to the doctor for a careful check. The good news is that millions of children now can have yearly eye exams and following treatment, including eyeglasses.

II. Protect against UV rays(紫外线).

Long-term stay in the sun creates risk to your eyes. No matter what the season is, it’s extremely important to wear sunglasses.    2    .

III. Give your eyes a break.

Two-thirds of Americans spend up to seven hours a day using computers or other digital products.     3    . Experts recommend that people practice the 20/20/20 rule: every 20 minutes, take a 20-second break and look at something 20 feet away.

IV. Eat your green.

As part of a healthy diet, eat more fruits and vegetables each day. Vitamins C and E help protect eyesight and promote eye health.

V. Practice safe wear and care of contact lenses (隐形眼镜).

Many Americans use contact lenses to improve their eyesight. While some follow the medical guidance for wearing lenses, many are breaking the rules and putting their eyesight at risk.    4    . Otherwise, you may have problems such as red eyes, pain in the eyes, or a more serious condition.

6 . Be at your best!

What does your brain need to work well? Here are some things it needs.

Good food

Experts say that breakfast is much more important than any other meal.     1    . So don’t miss breakfast—especially before an exam! But you need to eat a good breakfast—junk food won’t work.

A regular supply of energy

Your brain needs a regular supply of energy, so you need to eat carbohydrates (碳水化合物). They’re found in bread, rice, pasta and beans.     2    . They work more quickly than bread and rice, so they give you a short burst (爆发) of energy, but afterwards you feel more tired.

A continuous supply of oxygen (氧气)

Your brain needs oxygen, which it gets from exercise.     3    . You also need a good supply of iron because iron helps your blood to carry oxygen round your body.

Water

    4    . Not getting enough water will stop your brain from working well. And remember, water isn’t as expensive as sweet drinks!

    5    

Your brain needs several hours’ sleep, so it can ‘update’ itself, just like a computer. Experts say that when you study for a test or an exam, you should get some sleep as quickly as possible after you’ve finished studying. This helps you to remember what you’ve learned.

8 . A new study, published this week in the journal Frontiers in Veterinary Science, reveals that non-human animals' tears are not so different from our own. The chemical similarities are so great, in fact, that the composition of other species' tears—and how they're adapted to their environments-may provide insights into better treatments for human eye disease.

Previously, scientists had studied closely only the tears of a handful of mammals, including humans, dogs, horses, camels, and monkeys. In the new study, Brazilian veterinarians analyzed the tears of reptiles and birds for the first time , focusing on seven species.

Tears, which are released from tear tubes, form a film over the eye that's composed of three ingredients: mucus, waler, and oil. The mucus coats the eyes surface and helps to attach the film to the eye, the water is a natural salty solution containing crucial proteins and minerals, and the oil prevents the eye from drying out.

Humans are the only known species to produce emotional tears; the expression "crocodile tears," which refers to a person's phony display of emotion, comes from the mysterious tendency of crocodiles to release tears as they eat.

But tears play key roles beyond weeping, notes Lionel Sebbag at Iowa State University, who was not involved in the new research. They help with vision by lubricating and clearing the eye. They also protect the eye against infection and provide nutrition to the cornea, the eye's clear outer layer, which lacks blood tubes, he says.

Learning how reptiles and birds' use tears may also inspire new medications for conditions such as dry eye, which occurs when tear tubes don't produce enough oil. The disease, common in cats, dogs, and people, can sometimes lead to blindness.

9 . The spine (脊柱) stands at the center of your health, providing your body with structure and support. It also contains a major collection of nerves that deliver electric signals from the rest of the body to your brain. Since your spine is so central to health, it’s important to take care of it.

Staying in a good position is one of the most important things you can do to keep your spine healthy. A proper position means standing or sitting while keeping your spine straight, except for its natural bending. Positions play a vital part even when you’re asleep. Stomach sleeping is far from a good idea. Many people prefer sleeping on their side, which is in the interests of their spine. Sleeping on your back has lots of benefits yet can cause lower back pain and put some pressure on your spine.

Staying still for too long — even if your position is good — can be hard on your back. Especially if you work at a task most of the day, it’s important to get up and stretch (伸展) periodically. Therefore, exercise is also a key part in the health of your spine. Stretches can help the muscles (肌肉) around your spine relax. Strength exercises with light weights or body weight exercises like push­ups can also help by strengthening the muscles. However, don’t overdo the exercise, as repeated movements can hurt the muscles around the spine, as trying to lift heavy weights with poor technique.

Your diet also affects the health of your spine because many vitamins are necessary for bones and nerves. In particular, vitamin B and omega­3 fatty acids help keep nerves healthy. Another important part is vitamin D, which is required for strong bones. Vitamin D can come from some foods, but it’s also absorbed from sunlight, so it may help to do some exercises outside. At last, many of the actions necessary to keep a spine healthy are similar to those used to protect your health in other ways. So protect your back, and the rest of the body will benefit.

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10 . Have you ever wondered if you see the same colours as other people? Most people know what blue is when they see it. They see the colour and call it “blue” because they were taught the word and associated it with what they saw. But how do you know what you see as blue isn’t someone else’s red?

The ability to perceive colours is down to receptors in our eyes. Light waves hit these receptors and they react depending on which colour the light is, sending signals to the brain. The brain then decodes these signals to determine which colour light the eyes are receiving. Some people’s receptors are more developed than others. People with weaker receptors usually have colour blindness. The inability of the receptor to interpret the light waves correctly means that some people cannot tell different shades of a colour.

In the past, most scientists would argue that everyone saw colours in the same way. However, research was conducted on monkeys, in which they were injected with a virus affecting their receptors. This enabled them to understand more colours than usual and brought an interesting discovery. Normally monkeys can only see blue and green, but the virus allowed monkeys to see red. The neurons (神经元) in their brains adapted to be able to understand new colours, which might mean the neurons in our brains are not instinctive (本能的) to automatically understand which colour is which. This implies that our brains and neurons may adapt depending on our stimulus (刺激) during the developmental phase. Colour could be a very personal experience, unique to everyone.

So, the next time you talk about your favourite colour, just remember if yours is blue and your friend says red, you might actually be thinking about the same colour. What if everyone in the world has the same favourite colour, but just calls it different names?