Final answer:
Foods that can help Caleb increase his vitamin D intake include fish, store bought cow's milk, fortified soy milk, and eggs. These are either naturally rich in vitamin D or fortified with it.
Step-by-step explanation:
To increase his vitamin D intake, Caleb can choose the following food items: fish, store bought cow's milk, fortified soy milk, and eggs. These items are known to be rich in vitamin D or are fortified with it. For example, fish such as salmon and tuna are naturally high in vitamin D. Milk and soy milk in the U.S. are often fortified with vitamin D, generally containing about 100 IU per 8-ounce glass. Eggs also contain vitamin D, primarily in the yolk.
Broccoli, fresh squeezed orange juice, and avocado are not significant sources of vitamin D and therefore wouldn't contribute much toward meeting Caleb's dietary requirements for this nutrient. It is important to note that while vitamin D can be synthesized by the skin upon exposure to sunlight, dietary intake becomes crucial for individuals with limited sun exposure or those who have higher requirements for this vitamin.
Vitamin D can be obtained from certain food sources. In this case, Caleb needs to increase his vitamin D intake, so he should focus on consuming foods that are rich in vitamin D. Fish, such as salmon and tuna, is naturally high in vitamin D. Store-bought cow's milk and fortified soy milk are also good options for increasing vitamin D intake. Eggs are another potential source of vitamin D that Caleb can include in his diet.