Answer to Question 1
There is no evidence that shows a significant difference in the effectiveness of one form of vitamin over another.
Answer to Question 2
Yes, stress does increase our need for vitamins and minerals. There could be several aspects to this answer The instructor may want to define the areas the student should concentrate on. For example: stress that causes an increase in the basal metabolic rate would cause an increased need for energy and the corresponding vitamins and minerals necessary for energy production (consider the B vitamins needed in glycolysis and the TCA cycle). Physical stress that includes strength exercises will cause calcium to be deposited in the bones, causing an increase in the need for calcium. Stress that is aerobic in nature requires additional oxygen which increases the need for iron. There are numerous examples that could be provided. The stress referred to in this case study is psychological and physical to a degree in that SR is not eating correctly and is not getting enough physical activity. This type of stress can cause a decrease in her immune system which will precipitate a need for the nutrients necessary for a healthy immune system.