We have been told 1000s of times that vitamin D is important for our health. Chiropractic Intern Mekenna Bowers discusses what happens with vitamin D in the body and why it is so important!
Why via the sunlight?
UV-B radiation is crucial for the synthesis of vitamin D in the body. This is why we have all been told that we need sunshine to get our vitamin D. Our skin houses 7-dehydrocholesterol which is converted to previtamin D3 with UV-B radiation. Thermal energy (heat) then allows previtamin D3 to convert to vitamin D3 in the skin. Vitamin D3 is shipped off to the liver where it is converted to 25-hydroxyvitamin D (calcidiol) and then 1,25-dihydroxycholecalciferol (calcitriol),which is the active form of Vitamin D.
How else can get vitamin D?
We can also absorb vitamin D from our diet, especially from oily fish and fortified dairy products. Unfortunately, most adults only consume less than ⅓ the recommended daily amount of vitamin D, and studies have found that between 70% and 97% of Canadians have vitamin D insufficiency. Additionally, to low dietary intake, the high Canadian latitude means less direct sunlight and less UV-B. Winter is especially problematic due to lower UV index and when we go out, we’re all bundled up against the chill which limits exposed skin surface to collect UV rays. Additionally, many of us wake up to go to work before the sun is up and return home after sundown.
Why should be be so concerned about getting enough vitamin D?
It contributes to muscle growth, development, and muscle contractions, allowing us to move, lift and live. It activates the synthesis of serotonin from tryptophan in the brainstem, which is important for mood, sleep, digestion, blood clotting, and sexual desire.
What else does it do?
Vitamin D also has a large role in regulating the concentration of available calcium in the blood. It does this by helping absorption of calcium and phosphate from the digestive system, increasing reabsorption in the kidneys, and regulating storage in the bones. Calcium acts on our blood vessels, muscles, nerves, hormonal organs, on top of contributing to bone health. Phosphate contributes to cell structure, DNA/RNA, and proteins, and is also responsible for many cell reactions and functions.
What happens when levels are low?
When vitamin D levels are low, we might experience what happens when the above functions don’t occur as normal, such as muscle weakness, fatigue, chronic pain sensation, and depressed mood. Many people report feeling down, low energy, and more tired in the winter. This can make it challenging to stay motivated and maintain healthy habits such as going for walks, socializing with friends, going to the gym, eating well, ect.
So what should we do?
All year round, especially during the winter, we should be ensuring we get adequate sun exposure and good vitamin D dietary intake to ensure our levels are sufficient. It is difficult to determine how much sunlight is “enough” in the winter, but suggestions are to aim for 20-30 minutes several times a week. Daily vitamin D minimal intake is advised to be 600 IU (15 mcg) with the best food sources being: 1 tablespoon of cod liver oil provides 170% daily value, 3 oz trout 81%, 3 oz salmon 71%, 1 cup fortified milk 15% (milk alternatives 13-18%). If oily fish is not to your taste, we can discuss the best vitamin D supplement to ensure you’re getting enough for optimal functioning.
It is important to take these small and mighty steps for our health. Ensuring enough vitamin D will mean allowing many of our body systems to to their job and keep us feeling well.
Mekenna Bowers
References:
https://www.bfs.de/EN/topics/opt/uv/effect/acute/vitamin-d.html
https://www.hsph.harvard.edu/nutritionsource/vitamin-d/
https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/