The second era was initiated in the early decades of the twentieth century and might be called "the vitamin period." Vitamins came to be recognized in foods, and deficiency syndromes were described. As vitamins became recognized as essential food constituents necessary for health, it became tempting to suggest that every disease and condition for which there had been no previous effective treatment might be responsive to vitamin therapy. At that point in time, medical schools started to become more interested in having their curricula integrate nutritional concepts into the basic sciences. Much of the focus of this education was on the recognition of vitamin deficiency symptoms. Herein lay the beginning of what ultimately turned from ignorance to denial of the value of nutritional therapies in medicine. Reckless claims were made for effects of vitamins that went far beyond what could actually be achieved from the use of them.
恩恩，十分感谢，下面的能继续么？
追答In the third era of nutritional history in the early 1950's to mid-1960s, vitamin therapy began to fall into disrepute. Concomitant with this, nutrition education in medical schools also became less popular. It was just a decade before this that many drug companies had found their vitamin sales skyrocketing and were quick to supply practicing physicians with generous samples of vitamins and literature extolling the virtue of supplementation for a variety of health-related conditions. Expectations as to the success of vitamins in disease control were exaggerated. As is known in retrospect, vitamin and mineral therapies are much less effective when applied to health-crisis conditions than when applied to long-term problems of undernutrition that lead to chronic health problems.
在第三段时期始于五十年代中期到六十年代中期，维生素疗法开始产生争议。营养学教育在医学学校也因为这个原因不再像原来一样受欢迎。而药品公司发现他们的维生素销量蹿升正是在这发生的十年之后。对维生素疗法对疾病治疗的期望也有所夸大。正如过去发生的一样，维生素和矿物质疗法相对于应用到治疗因缺乏营养所导致的长期疾病来说，在治疗一般的健康危机疾病时没有那么有效。
我手上的资料直到这里了。
英文系学生，托福考生，欢迎交流