Sunlight, Vit D and Health.

 March 21, 2026

 

Selamat Hari Raya Adilfitri!  Eid Mubarak! 

 It's a long weekend, and a great celebration for Muslims.

Sunshine and health and wellbeing are linked. I live in tropical beautiful Penang island, Pearl of the Orient!  Though there are lots of sunny days, I was having a sun avoiding behavior.  

In 2016, when I was very puzzled by my faster than normal ageing rate of drop for my hip bone density. (an indication that my hip might be approaching osteoporosis early than I would like --which would mean risk of broken bone with trivial trauma/fall becoming higher, which mean I would need to adjust my lifestyle - exercise choice if I would like to prevent a hip fracture).  

 

 

I decided not to assume that my Vit D level would be normal, and got myself tested. Lo and behold --, it was extremely low.  So, now, I do not try to walk very fast, when I am under the sun.  But due to my work hours and work nature, beside ageing, I also need to supplement Vit D (average of daily 2000 iu) to ensure my result falls nicely in the normal range.

 

In 2021, I analysed a series of 1600 Vit D test results in my hospitals ( all tests done in my hospital between 2020 to 2021 June), 85% fell in the insufficient, and deficient (lower than insufficient) zones.  (Of course that set of data might have been affected by Covid 19 - MCO.  

Sunlight helps us produce vitamin D—an essential nutrient that’s recognised for its importance in maintaining healthy bones. While we can get some vitamin D from food, about 90% of our daily requirement comes from exposure to the sun. However, as a consequence of our sun-smart behaviour, deficiency of vitamin D is becoming a growing world-wide problem, including in my locality.

I read in my health on line course that:

When ultraviolet B light in sunlight strikes our skin, it activates a substance in our skin known as pro-vitamin D3, converting it to pre-vitamin D3. This molecule undergoes isomerisation, which means it changes shape, resulting in a change in its properties. It’s then released into the bloodstream, and when it arrives in the liver it is further modified into a storage form of vitamin D. When this substance reaches the kidneys, it is finally converted into the biologically active form of vitamin D—the molecule that plays an active role in a variety of functions in our bodies.[3] The vitamin D that is in food is less biologically active than the type produced in our bodies, and because we can make our own vitamin D, it’s often called a hormone rather than a vitamin.[4] It should be noted that as we get older, we have less pro-vitamin D3 in our skin, and this contributes to vitamin D deficiency in older people.[5] (the numbers are referring to references; if you are interested, you may sign up this free health course at www.discoverhope.my Living Well course and read in lesson 11 about Sunshine). 

Beside bone health, Vit D has many other functions including prevention of cancers (ie colon, breast), diabetes, production of melatonin, Brain Derived Neurotrophic factor (related to brain health, sleep, cognitive function) etc.

 So, in short, for health, go outdoor this weekend, and get some sunshine. And in case your lifestyle is like mine, take a Vit D supplement.