Be kind. unwind.

Do you have an idea what nutrient is more likely to be deficient in this season?

Vitamin D! In the UK, winter sunlight (Nov-Mar) hasn’t got enough ultraviolet B (UV-B) radiation which is responsible for vit D synthesis within the skin.  

Here’s how vitamin D is synthesized and used:

1.   As the sunlight shines on you, UV rays strike your skin and trigger the synthesis of cholecalciferol1 (CCF) from cholesterol. However, CCF from dermal synthesis is inactive.

2.   CCF is then carried in the bloodstream to the liver, where a hydroxyl2 group is added to the 25th carbon of CCF, producing 25-hydroxylCCF (prohormone).

3.    Following circulation, another hydroxyl (-OH) group is added to the carbon 1 of the prohormone in kidney, forming 1,25-dihydroxylCCF, (biologically active form of vitamin D)

4.   Vitamin D diffuses3 into cells in Gastro Intestinal Tract (GIT) and bind to its receptor, and act as a transcription factor that modulate the gene expression of transport protein involve in calcium absorption in the intestine.

5.   More transport proteins are synthesized and, therefore, cells in GIT are more permeable to calcium. More calcium is absorbed in GIT. And we all know, calcium makes strong is essential for strong bones!

So does that mean: winter = vit D deficiency? No, don’t panic! Sunlight isn’t the only vitamin D source. We can get it from different foods and supplements! Oily fish, eggs, fortified milk (also a calcium source) and cereals are a good source of vitamin D.

Appendix

1. Cholecalciferol, CCF is one example of vitamin D, it’s worth noting than vitamin D is not a single molecule but refers to a group of fat-soluble secosteroids responsible for enhancing intestinal absorption of electrolytes especially, calcium).

2. hydroxyl group: a general term for –OH group, the more specific term will be like secondary alcohol/ tertiary alcohol and the phenolic hydroxyl group (phenol). And more commonly in chemistry, the –OH- that we heard is an anion.  

3. Diffuse: It is worth take note that vitamin D is a lipid-soluble vitamin and hence it is able to diffuse through cell lipid membrane easily and hence it is not surprised that its target (receptor) is located inside the cell, or more precise the nuclei of the cell.

Reference:

EVERYONE

2nd Edition of PYSH aka Prints you should have Part 10 this time by Andreas Lie

Disconnect - Get it

Untitled 2 - Get it

Untitled 5 - Get it

Chaos - Get it

Fingerprint - Get it

Untitled - Get it

Kjærleik - Get it

Drift - Get it