Vitamins, minerals, and multivitamin supplements won’t protect you from cancer, heart disease, or help you live longer, the US preventive Services Task Force said in the new guidelines released Tuesday in the Journal of the American Medical Association on June 21.
Following the release of the previous guidelines in 2014, the Task Force reviewed 84 studies testing vitamins in almost 700,000 people, including 52 new studies.
However, the conclusion is still the same as that of 2014: If you are a healthy adult who is not pregnant, there is not enough evidence of benefits to expand one’s life in taking vitamin E, vitamin D, vitamin A, calcium tablets, carotene (胡萝卜素), vitamin B3, vitamin B6, vitamin C and other supplements. The Task Force does not recommend taking carotene supplements to prevent cardiovascular (心血管) disease or cancer, with enough evidence that it “may increase the risk of death, the death rate of cardiovascular disease and the risk of lung cancer”. Nor should people take vitamin E, “because vitamin E is not likely to be beneficial in reducing death, cardiovascular disease or cancer risk,” the Task Force said.
“Lifestyle recommendations for preventing chronic diseases (慢性病) should continue to focus on evidence-based methods, including balanced meals rich in fruits and vegetables and physical activity,” Dr. Jeffrey Linder, Director of General Internal Medicine at the Feinberg School of Medicine of Northwestern University in Chicago, wrote in an additional commentary.
Take the Mediterranean diet for example. Eating the Mediterranean way, which focuses on a plant-based diet, physical activity and social engagement, can reduce the risk for high cholesterol, dementia (痴呆), memory loss, depression and breast cancer. And numerous studies found meals from the sunny Mediterranean region have also been linked to weight loss, stronger bones, a healthier heart and longer life.
Another evidence-based approach is the DASH diet, which stands for “dietary approaches to stop hypertension (高血压)”. Many studies have shown that this diet successfully reduces hypertension. Both the Mediterranean and DASH diets avoid processed foods and focus on fruits, vegetables, beans, whole grains, nuts and seeds.
“Rather than focusing money, time, and attention on supplements, it would be better to emphasize lower-risk, higher-benefit activities...following a healthy diet, getting exercise, maintaining a health y weight, and avoiding smoking,” Linder and his colleagues wrote.
However, certain groups of people do need to take specific vitamins. Some seniors may need vitamin B12 and vitamin B6 supplements because they absorb fewer vitamins from food as they age. Because the elderly often have less sun exposure than younger people, they may need vitamin D supplements, but the dosage must be checked by the doctor, as too much vitamin D intake can be harmful.
8. What can we learn from the Task Force?
A.Vitamins must be useful to prevent cardiovascular disease or cancer. |
B.Doctors want to control cardiovascular disease. |
C.It’s necessary for all people to take vitamins. |
D.In some regard, taking vitamins is not beneficial. |
9. How many kinds of diets are mentioned to reduce death, cardiovascular disease or cancer risk?
A.One | B.Two. | C.Three. | D.Four. |
10. According to the passage, who can take vitamins regularly?
A.A 40-year-old healthy worker. | B.A 15-year old healthy boy. |
C.A 34-year-old healthy lady. | D.A 69-year-old healthy man. |
11. What’s the main idea for the text?
A.The history of vitamins. |
B.The functions of vitamins. |
C.Taking vitamins to prevent diseases may fail. |
D.People’s attitudes towards vitamins. |