Vitamin D is an essential hormone that is responsible for maintaining bone health and regulating the immune system. In recent years, there has been controversy surrounding the appropriate level of vitamin D in the body and whether low levels of vitamin D can cause various illnesses. In this article, we will explore the vitamin D controversy and provide insight into the current scientific research surrounding vitamin D.
Firstly, it is important to note that vitamin D is not actually a vitamin but a hormone that is produced by the skin in response to sunlight. The hormone is then converted into its active form in the liver and kidneys. This active form of vitamin D is responsible for maintaining healthy levels of calcium and phosphorus in the body, which are critical for maintaining strong bones and teeth.
The recommended level of vitamin D in the blood is measured in nanograms per milliliter (ng/mL). According to the National Institutes of Health (NIH), a healthy level of vitamin D in the blood is between 20-50 ng/mL. However, some researchers argue that this range should be higher, with a recommended level of 30-80 ng/mL.
Low levels of vitamin D in the body have been correlated with various illnesses, including cardiovascular disease, diabetes, and cancer. However, it is important to note that correlation does not imply causation. While low levels of vitamin D may be associated with these illnesses, it has not been proven that low vitamin D levels actually cause these illnesses.
Additionally, the relationship between low vitamin D levels and illness may be explained by reverse causation. For example, individuals who are already ill may be more likely to have low vitamin D levels due to factors such as inflammation, poor nutrition, lack of sunlight exposure, or medications. Therefore, it is important to consider these factors when interpreting the correlation between low vitamin D levels and illness.
Despite the controversy surrounding the appropriate level of vitamin D in the body and its relationship with various illnesses, it is clear that maintaining healthy levels of vitamin D is important for overall health and well-being. Vitamin D deficiency can lead to a compromised immune system, weakened bones, muscle weakness, and an increased risk of fractures. Therefore, it is recommended that individuals who are at risk of vitamin D deficiency, such as those who are elderly, have dark skin, or live in areas with limited sunlight exposure, should consider adopting food and lifestyle choices that will increase levels of this critical hormone.
In conclusion, the vitamin D controversy highlights the need for further research into the appropriate level of vitamin D in the body and its relationship with various illnesses. While low vitamin D levels have been correlated with illness, it has not been proven that low vitamin D levels actually cause these illnesses. Furthermore, the relationship between low vitamin D levels and illness may be explained by reverse causation. Despite these controversies, maintaining healthy levels of vitamin D is critical for maintaining bone health and overall health and well-being. Individuals should work with their healthcare provider to determine the appropriate level of vitamin D for their individual needs.
Here are some sources that can provide additional information about the vitamin D controversy, its classification as a hormone rather than a vitamin, and the correlation between low vitamin D levels and various illnesses:
Holick MF. Vitamin D deficiency. N Engl J Med. 2007;357(3):266-281. doi:10.1056/NEJMra070553
Manson JE, Brannon PM, Rosen CJ, Taylor CL. Vitamin D Deficiency - Is There Really a Pandemic? N Engl J Med. 2016;375(19):1817-1820. doi:10.1056/NEJMp1608005
Carlberg C, Haq A. The concept of the personal vitamin D response index. J Steroid Biochem Mol Biol. 2018;175:12-17. doi:10.1016/j.jsbmb.2016.12.014
Bikle DD. Vitamin D: an ancient hormone. Exp Dermatol. 2011;20(1):7-13. doi:10.1111/j.1600-0625.2010.01214.x
Manson JE, Bassuk SS, Lee IM, et al. The VITamin D and OmegA-3 TriaL (VITAL): rationale and design of a large randomized controlled trial of vitamin D and marine omega-3 fatty acid supplements for the primary prevention of cancer and cardiovascular disease. Contemp Clin Trials. 2012;33(1):159-171. doi:10.1016/j.cct.2011.09.009
Durup D, Jørgensen HL, Christensen J, Schwarz P, Heegaard AM, Lind B. A reverse J-shaped association of all-cause mortality with serum 25-hydroxyvitamin D in general practice: the CopD study. J Clin Endocrinol Metab. 2012;97(8):2644-2652. doi:10.1210/jc.2012-1176
Melamed ML, Michos ED, Post W, Astor B. 25-hydroxyvitamin D levels and the risk of mortality in the general population. Arch Intern Med. 2008;168(15):1629-1637. doi:10.1001/archinte.168.15.1629
Manousaki D, Mokry LE, Ross S, Goltzman D, Richards JB. Mendelian randomization studies do not support a role for vitamin D in coronary artery disease. Circ Cardiovasc Genet. 2016;9(4):349-356. doi:10.1161/CIRCGENETICS.116.001374
Vaidya A, Forman JP. Vitamin D and hypertension: current evidence and future directions. Hypertension. 2010;56(5):774-779. doi:10.1161/HYPERTENSIONAHA.110.152306