Having been on holiday in Spain for 2 weeks, where I soaked up the sun as I partook in several hiking trails in Alicante's Costa Blanca, to then return home to take a blood test, the last result I expected to have was a low vitamin D rate. As a frequent hiker and climber, maintaining a good vitamin D rate is very important as scientific research suggests lack of vitamin D can contribute to stress injuries. So, this summer whether you are sunbathing or out for a run in the sun, it is important to note that you may not be taking in a sufficient amount of vitamin D as you may have expected.
Vitamin D is a group of fat-soluble secosteroids which can be obtained from sun exposure, food and supplements. The liver and kidneys convert the vitamin into its active form, where it increases the regulation of calcium and phosphorus, and promotes the regulation of bone mineralization. Vitamin D also can affect function of the immune system and influence cell growth.
As athletes we demand and apply a great amount of pressure to our bones so it is of no surprise that parts of the body can face a great amount of stress. Scientific studies have shown that an ' association was seen in patients with a stress fracture and their vitamin D levels' ( Miller). One study published by the American College of Foot and Ankle Surgeons followed that more than half of the 53 patients with stress fractures between the years of 2011 and 2014 had Vitamin D levels below 30 ng/mL, a considerably low Vitamin D level.
Whilst exposing your skin to the sun's UV rays is considered one of the best ways to achieve vitamin D intake, it is highly recommended that we spend only 10-30 minutes as too much sun can cause damage. But do not fret! As there are many other ways in which you can improve your Vitamin D levels. Good sources of Vitamin D can be found in chia seeds, oily fish such as salmon, sardines, mackerel, tuna. It also can be found in red meats, liver and egg yolks. There are even supplements, such as ergocalciferol and cholecalciferol, which can assist in obtaining Vitamin D levels.
It is recommended that the safe upper limit of intake is 4,000 IU per day so It is important to find a balance when obtaining vitamin D.
By Jessica Dixon, intern 2022.
Miller, Jason R et al. “Association of Vitamin D With Stress Fractures: A Retrospective Cohort Study.” The Journal of foot and ankle surgery : official publication of the American College of Foot and Ankle Surgeons vol. 55,1 (2016): 117-20. doi:10.1053/j.jfas.2015.08.002