under what three conditions would intakes of vitiamin c above the RDA be desirable?

Answer 1

the RDA is for the sedentary individual. people that are physically active, competitive athletes, etc. need and can utilize more nutrients. vitamin c is also water soluble so there is no storage capacity for it in the body.

Answer 2

As mentioned above the RDA only represents levels for the average of the population and refers specifically to macronutrients. There are similar recommendations for such micronutrients as vitamin C called RNI this stands for reference nutrient intake. People who need more than this are advised a to intake a volume called the upper RNI and represent 2.5% of the population.

These people include pregnant women, smokers and people with stress related illness.

Hope this helps

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