A male college student gets over 200% of iron, zinc and calcium per day.

A male college student intakes 3447 calories/day (101% RDA). His iron intake is 284% RDA. His zinc intake is 282% RDA. His calcium intake is 346% RDA. These values are 3-day averages. Should he attempt to lower his intake of these minerals? Why or why not?

There is no RDA for calories. We can estimate what a person’s basal energy needs are using height, weight, sex, and age (Harris-Benedict formula). In addition, an activity factor (to cover what a person does during a typical day) can be added to the basal calorie needs. Structured exercise programs can add additional calorie needs. If this male college student has estimated that around 3400 calories are what he needs per day without gaining body fat, then the calorie intake at 3447 is not significant.

The greater than 100% RDA of iron, zinc, and calcium are fine. Excess minerals will be excreted via the gastrointestinal tract. The above average intakes of these minerals suggest that the student is a big meat eater and milk drinker (more than 3 cups per day). Maybe, this student should eat more grains, bread, rice or pasta to increase the carbohydrate content of his diet to get a better balance of nutrients.

A three day or weeks average of nutrients is a better indicator of nutrient intake that just analyzing a meal or just one day.