The RDA for iron is 18 milligrams per day for adult women. Tina usually consumes about 15 milligrams of iron per day. She is a healthy young woman with no condition that significantly increases her needs for iron. Which of the following statements is true about her consumption of this nutrient A. Only if her intake is consistently less than 70% of the RDA would she be at great risk of nutritional deficiency. B. are established for nutrients for which there is not enough information to set RDAs.

A. Only if her intake is consistently less than 70% of the RDA would she be at great risk of nutritional deficiency.

Explanation:

In an adult women blood contain 70% of the entire body iron.However menstruation  takes certain proportion of  iron in menstrual flow .Besides, 1 mg of iron is lost daily inform the mucous membranes and regular skin sheds. Therefore  daily  dietary and supplement intake of iron  should be consumed  so that  the set point of 70% is  maintained. Provided Tina can maintain  her  blood plasma iron concentration at  70%,  with her 15 mg intake but not less than this value she would not not experience any nutritional deficiencies.  

Thus, it is when her blood plasma levels(body %) falls below the blood  iron percentage of 70, that she will be at risk.

Explanation:

a unit of heredity that is transferred from a parent to offspring and is held to determine some characteristic of the offspring.