Chapter 11 Case Study: Low Serum Vitamin D

1. Which of the following is NOT a likely cause of vitamin D deficiency in the elderly?

Reduced absorption of magnesium

6. Joan has been taking a multivitamin supplement every day that provides 1,500 µg of vitamin A. The RDA for Vitamin A for a woman of Joan's age is 700 ug/day and the Upper Limit (UL) for vitamin A is 3000 ug/day. Joan's supplement supplies what percent of the RDA for Vitamin A?

214

3. Because Joan is concerned about skin cancer, she uses a sunscreen when she is outside. At what SPF level will sunscreen start to interfere with vitamin D synthesis?

8

4. Joan's low serum vitamin D levels and low dietary vitamin D intake indicate that she is vitamin D-deficient. She needs a vitamin D supplement to raise blood vitamin D levels and to lower the risk of fractures. Based on her vitamin D Recommended Dietary Allowance, or RDA, what supplement dose should she take daily?

800 IU

8. Which of the following food groups is rich in vitamin K?

Dark green, leafy vegetables

2. Of the foods Joan eats, which is the best source of vitamin D?

Fortified milk

7. Analyzing Joan's diet and supplement use, what might explain why she now has osteoporosis?

Her low vitamin D and calcium intakes and her history of taking a multivitamin pill containing 5000 IU of vitamin A per day can all lead to the development of osteoporosis.

5. If Joan wants to increase her intake of vitamin A, which of the following foods would be best?

Sweet potatoes