研究发现：维生素片大多没啥用 吃错还会致病

Vitamin and mineral supplements are a staple in many people's diets, but there is increasing evidence to suggest the most popular ones are essentially useless.

维生素和矿物质补充剂是许多人日常膳食中的固定组成部分，但越来越多的证据表明，最受欢迎的一些维生素补充剂其实都没什么用。

A new systematic review of data and trials published between January 2017 and October 2017 found that many popular multivitamins – as well as vitamin C, vitamin D, and calcium supplements – had no real advantage to people's health and that there was no evidence taking them reduced the risk of cardiovascular disease, heart attack, stroke, or early death.

一项对2017年1月至2017年10月间发布的数据和试验的系统回顾发现，维生素C、维生素D、钙质补充剂和许多受欢迎的复合维生素对人们的健康没有实质性的好处，而且没有证据表明服用这些维生素能够降低心血管疾病、心脏病发作、中风或早逝的风险。

The study, published in the Journal of the American College of Cardiology, was led by researchers at St. Michael's Hospital and the University of Toronto.

这项发表在《美国心脏病学会期刊》上的研究是由圣米高医院和多伦多大学的研究人员带头开展的。

"We were surprised to find so few positive effects of the most common supplements that people consume," said Dr. David Jenkins, the lead author of the study.

研究报告的主要作者戴维·詹金斯博士称：“我们惊讶地发现，人们最常服用的补充剂居然收效甚微。”

"Our review found that if you want to use multivitamins, vitamin D, calcium or vitamin C, it does no harm – but there is no apparent advantage either."

“我们的回顾发现，如果你想服用复合维生素、维生素D、钙片或维生素C，对你的身体是无害的，但也没有明显的益处。”

There were, however, a few apparently advantageous supplements. Folic acid and B vitamins with folic acid may reduce the risk of cardiovascular disease and stroke, the study found.

不过，研究也发现了几种对人体明显有益的补充剂。叶酸和含有叶酸的复合维生素B或许能降低患心血管疾病和中风的风险。

Niacin (a form of vitamin B3) and antioxidants, meanwhile, were associated with a higher risk of death by any cause, albeit a very small increase.

此外，烟酸（维生素B3）和抗氧化剂会导致死亡风险升高，不过只是略微升高。

The researchers say these higher risks could be related to niacin's adverse effects on blood-sugar levels, or that when taken in high doses, antioxidants can be harmful.

研究人员称，这可能和烟酸对血糖水平的负面影响有关。研究指出，大量服用抗氧化剂会对人体有害。

Alternatively, it could have something to do with people sometimes thinking that taking vitamins can be a substitute for a healthy, balanced diet.

另一方面，服用维生素无益也和人们的观念误区有关，有些人认为服用维生素可以替代健康平衡的膳食。

"These findings suggest that people should be conscious of the supplements they're taking and ensure they're applicable to the specific vitamin or mineral deficiencies they have been advised of by their healthcare provider," Jenkins said.

詹金斯说：“研究结果表明，人们应该了解自己服用的补充剂，听从医嘱，确保这些补充剂能补充自身所缺乏的某种维生素或矿物质。”

The vitamins the team reviewed were A, B1, B2, B3 (niacin), B6, B9 (folic acid), C, D, and E, as well as carotene, calcium, iron, zinc, magnesium, and selenium.

研究团队的研究对象包括维生素A、维生素B1、维生素B2、维生素B3（烟酸）、维生素B6、维生素B9（叶酸）、维生素C、维生素D和维生素E，还有胡萝卜素、钙、铁、锌、镁和硒。

Research has found that some vitamins are more useful than others. For example, zinc has been linked to shortening the effects of a cold – something vitamin C doesn't do, despite what people think.

研究发现，一些维生素比其他维生素更有用。比如，锌能缩短感冒周期，而维生素C却不能，尽管人们一直以为维生素C能让感冒好得快。

Vitamin D can also be difficult to get from food, so if you're deficient, supplements may also be effective.

维生素D难以从食物中获得，所以如果你缺乏维生素D，那么服用补充剂会比较有效。

"In the absence of significant positive data – apart from folic acid's potential reduction in the risk of stroke and heart disease – it's most beneficial to rely on a healthy diet to get your fill of vitamins and minerals," Jenkins said.

詹金斯说：“除了叶酸可能降低中风和心脏病风险外，没有足够数据表明服用补充剂对人体有益，因此最好还是从健康膳食中获取你所需要的维生素和矿物质。”

"So far, no research on supplements has shown us anything better than healthy servings of less processed plant foods, including vegetables, fruits, and nuts."

“迄今为止，没有任何一项关于补充剂的研究显示有任何药物比摄入健康的轻度加工植物食品（包括蔬菜、水果和坚果）更好。”