【英语时差8,16】甜菜汁有益大脑（上）（在线收听）

 Is there any way to prevent or cure dementia? Unfortunately, no: there’s no cure for dementia. And there’s no sure fire way to prevent it, either. But scientists suspect that some types of foods may help the brain stay healthy longer. Right.For example, a study looked at the brain health properties of beet juice. Scientists have known that beet juice helps lower blood pressure. That’s because it’s high in nitrates chemicals that help open blood vessels and increase blood flow throughout the body. The study looked specifically at how drinking beet juice may also increase blood flow to the brain. Researchers studied the brains of fourteen older adults, all age 70 or older, who alternated between trying diets with and without beet juice.