Vitamin D – The Ultimate Guide

Vitamin D – The Ultimate Guide

Vitamin D- The Ultimate Guide

Vitamin D is very important for human survival. The same like vitamin A,E and K , also vitamin D is fat-soluble nutrient. The main source of vitamin D is sun.

Vitamin D is very important for our health and give us a lot of benefits:

It is very important for your immunity, cognition, bone health. Supplementing vitamin D might reduce the risks of cancer, diabetes, heart disease as well as multiple sclerosis.

Vitamin D is produced in the body from the cholesterol. But this process can go ahead only when the adequate amount of UV light is available, and this would be coming from the sun.

You can hear everywhere that most people are not having enough vitamin D in the body. The truth is that they don’t have an optimal level of vitamin D, but they are not deficient in this nutrient.

Vitamin D has many benefits and if optimal level is not present in the body, then supplementation is really recommended.

Vitamin D and Depression

Vitamin D insufficiency has been associated with depression. If you suffer from severe depression the supplementation might help. But if the level of vitamin D in your system is sufficient and you still suffer from depression, then supplementation might not help.

Saying that it doesn’t mean that low levels of vitamin D cause the depression. Most likely, when people are depressed, they don’t go outside as much, they are not exposed to the sun and therefore they produce less vitamin D. So that mean that depression might be a cause of lower levels of vitamin D.

Also being less outside means that most likely we exercise less. Lack of exercises affect our mood in a bad way.

Lower production of Vitamin D during the winter months, might be a possible cause of SAD (seasonal affective disorder).

There have been studies carried out about the correlation between the level of vitamin D and depression. Some studies found there is a correlation, and some have found, there isn’t.

How much and how to take vitamin D

The best way to find out the level of Vitamin D in your body is to run a blood test and being more specific you should undergo a 25-hydroxyvitamin D blood test. It does make sense to check your vitamin D level twice a year, in the middle of the summer and winter where we have the most and least sunlight.

Score less or equal to 20 ng/mL means that there is insufficient level of vitamin D in our body. It might affect 50% of the population worldwide.

The recommended daily intake of Vitamin D is set at 400 – 800 IU per day. This amount might be way too low for an adult especially in countries where the exposure to the sun is quite low.

In the USA and Canada, the upper tolerable intake is 4000 IU per day. But the research suggests that the real Upper Tolerable Intake is 10000 IU per day.

The lowest effective dose range to meet the needs of most of the population would be

1000-2000 IU per day.

We have got two forms of vitamin D when it comes to supplementation.

Vitamin D2 (ergocalciferol) and D3 (cholecalciferol). D2 is not as bioavailable as D3 and that is why we should always choose D3 over D2.

It should be taken daily, with meals or any source of fat such as olive oil, fish oil.


  • Nearly 50% of the world population have low levels of vitamin D which is less or equal to

20 ng/mL

  • Low levels of vitamin D have been linked to depression.
  • Sufficient level of Vitamin D is very important and beneficial for immune system, bone health, cognition, mood. It might reduce the risks of cancer, diabetes, heart disease as well as multiple sclerosis.
  • Seasonal affective disorder (SAD) might be a cause of decreased vitamin D production during the winter months
  • If your vitamin D levels are OK, supplementation is not going to improve your mood, but if the level is insufficient or low, there is a big chance that supplementation will help with depression
  • If you want to check the level of Vitamin D, you can do it through a 25-hydroxyvitamin D blood test