Biocultural effects on recent historic vitamin D deficiency in the United States and their role in spinal pathology

<p dir="ltr">Vitamin D directly influences blood-calcium homeostasis and skeletal health. Individuals who do not have enough vitamin D do not have adequate blood calcium levels leading to a cascade of metabolic deficiencies and health problems, including bone diseases like rickets and osteomalacia. These bone diseases weaken the cortical and trabecular bone and may influence the expression of load-bearing spinal pathology. This PhD uses a unique comparative approach examining historical contexts of the United States, osteobiographies, historic climate data, and biocultural variables to explore these two primary hypotheses: 1) biocultural variables in the recent historic past influence vitamin D deficiency; and 2) vitamin D deficiency weakens the vertebral column increasing the expression of spinal pathology. One hundred seventy-seven individuals living in the United States between the 1830s and 1940s were analyzed for the presence or absence of vitamin D deficiency and spinal pathology, and then traced through the historical record. Thirty individuals had confirmed vitamin D deficiency (osteomalacia 13; residual rickets 19), and twenty had potential vitamin D deficiency (osteomalacia 1; residual rickets 19). Two individuals had evidence of both residual rickets and osteomalacia. Results indicate that lived childhood and age at death are significantly associated with residual rickets, while year of birth and year of death were associated with osteomalacia. There were also correlations between osteomalacia and how long one lived in the North. Residual rickets was also significantly associated with one’s likelihood of developing lordosis; osteomalacia increased the appearance of lordosis and scoliosis. Based on the results, each individual’s unique biocultural variables, like latitude of childhood, length of time lived in a region, age, social race, sex, and occupation all influence one’s vitamin D levels. Vitamin D deficiency and these confounding variables influence spinal pathology expression.</p>