Health experts have long known that vitamin D is important for healthy bones and teeth. It may also help to protect the body against diseases such as diabetes and cancer. And now, researchers say vitamin D might help fight brain diseases called dementia（痴呆）.

Dementia is a brain disease that damages thinking and memory processes, which scientists call “cognitive（认知）abilities.” Dementia is difficult to treat. Taking care of someone who has dementia is extremely demanding. And the disease is very frightening to sufferers. Chris Roberts suffers from dementia. He says the worst part of living with this disease was getting lost while driving. “The worst thing that I found was getting lost in the car, not just forgetting where was going—I wouldn’t know where I was.” More than 47 million people around the world suffer from dementia. The World Health Organization reports that 60 percent of them live in low-and middle-income countries.

We get vitamin D from some foods like nuts, lentils（扁豆）and fatty fish. We also get vitamin D from the sun. But that is not dependable. In some parts of the world, there is not enough sunlight to provide enough vitamin D. Also, sunblock prevents the vitamin from entering the body. To add to the problem, the skin’s ability to process vitamin D weakens as a person ages.

Researchers at Rutgers University in New Jersey are exploring the relationship between vitamin D and dementia. The team recently measured vitamin D levels and cognitive ability in older people. Nutritional sciences professor Joshua Miller led the team. He said cognitive abilities differed among the study subjects. He said tests showed that about 60 percent of the group was low in vitamin D.

Everybody knows the importance of drinking enough water.As we all know, drinking water benefits your skin, muscles and organs.【小题1】

The major reason for that is related to human biological needs.When you're a baby, you're 75 percent water.Then, as the years get higher, you get drier.【小题2】   It helps you lose weight, according to a study from the University of Birmingham.

The researchers found that drinking 500 ml of water thirty minutes before a meal helped participants lose 10 more pounds than those who did not.【小题3】 All participants were advised to improve their diet and physical activity levels.84 overweight adults were involved.Among them 41 were told to “preload” with water, while 43 were told to control their water intake before eating.After 12 weeks, the participants instructed to “preload” with water lost 2.87 pounds more than those in the control group on average.In addition, the participants preloading with water before each of their three main meals every day lost 9.48 pounds over the 12 weeks.【小题4】

Dr.Helen Parretti, a lecturer at the University of Birmingham, had this to say of the study:   【小题5】Just drinking 500 ml of water, three times a day, before your main meals may help reduce your weight...and this could be an easy way for weight loss. Furthermore, it can be significant for an individual to lose extra weight, making a potential contribution to public health.

When answering a question, your silence might say more than your words. A new psychology study has found pausing before replying, even for just a few seconds, can make you seem more insincere or dishonest. That perception (感知) of dishonesty might not be too inaccurate, either. Numerous studies in the lab and in real life suggest people are slower to respond when they are not being truthful, possibly because it takes more mental work to block a truthful response or make up an alternative.

What’s been less clear is how well our lies have been fooling people. Some studies suggest delayed answers come across as insincere to the listener. Others find no relationship between the two, and still more have found the opposite: That a bit of hesitation increases our perception of sincerity. These findings are inconsistent and confusing. They are also mostly based on connection. Even the few studies that have actually looked at causal relationships often didn’t consider confusing factors that could also give away a liar or an insincere speaker.

The new research seeks to improve some of those limitations by examining thousands of people under a variety of conditions. Together, it involves more than 7,500 individuals from the United States, the United Kingdom, and France in a total of 14 experiments. On the whole, the authors found an immediate response was perceived as more sincere, while a delayed response, even a delay as brief as two seconds, was seen as more insincere.

“Evaluating other people’s sincerity is an important part of social interactions,” says consumer behavior researcher Ignazio Ziano. “It would be unfair for the responder, such as a crime suspect, if the response delay was mistakenly due to thought control or answer fabrication (捏造) when it was in fact caused by a different factor, such as simply being absent-minded or thoughtful,” explains Ziano.

Unfortunately, even when participants were instructed to ignore the response delays in one of the experiments, it only reduced their perception of insincerity; it did not completely remove it.