Which function is NOT associated with vitamin D?

Vitamin D is primarily known for its role in bone health and calcium absorption. When vitamin D is present in the body, it helps to regulate calcium and phosphate levels, which are essential for maintaining healthy bones and preventing conditions such as rickets in children and osteomalacia in adults. Additionally, vitamin D plays a significant role in immune function, supporting the body's ability to fight infections.

In contrast, protein synthesis is not a primary function of vitamin D. While vitamin D does have an indirect involvement in overall metabolism and cellular functions, its main recognized roles are centered around mineral regulation and skeletal health rather than directly influencing the mechanisms of protein synthesis. Thus, identifying protein synthesis as NOT associated with vitamin D highlights the distinction between the well-established functions of vitamin D and processes that are more directly linked to other vitamins and nutrients.