I take 2 x Vit D3 a day along with NAC.

Vitamin D3 is shown to boost glutathione production in the neuronal cells protecting them from damage inflicted by oxidative stress.  Vitamin D also helps to modulate the immune system to reduce inflammation throughout the body.

If you had zero sun exposure on significant areas of your bare skin, like most people, then research suggests it would require 9,600 IUs of vitamin D per day for most to reach 40 ng/mL, but individual requirements can vary widely, and you’ll need to get your levels tested to ensure you take the correct dosage required to get you into the optimal range.

The only way to gauge whether you might need to supplement, and how much to take, is to get your level tested, ideally twice a year, in the early spring, after the winter and early fall when your level is at its peak and low point. It’s important to note that vitamin D supplementation must be balanced with other nutrients, namely vitamin K2 (to avoid complications associated with excessive calcification in your arteries), calcium and magnesium

dr mercola

It’s now known that vitamin D is necessary not only for healthy bones but for health throughout the body. As a powerful epigenetic regulator, vitamin D influences the activity of more than 2,500 genes, and vitamin D receptors are present all over the body, including in the intestine, pancreas, prostate and immune system cells. Vitamin D plays a role in numerous diseases, including:

• Cancer
• Diabetes
• Acute respiratory tract infections
• Chronic inflammatory diseases
• Autoimmune diseases such as multiple sclerosis

The single most important method of optimizing your vitamin D levels is exposing enough of your skin to the sun during around solar noon, which is 12 to 1 p.m. (depending on daylight saving time) in the summer. Be careful to never get burnt while understanding that the primary reason most people burn is that they have too much linoleic acid in their fat and that is the molecule the sun damages, which leads to burns and skin cancers.

Not only will regular sun exposure help to optimize your vitamin D levels but it will also increase melatonin in your mitochondria, which will decrease oxidative stress and increase energy production efficiency. It will also help to metabolize vitamin A and optimize your immune function.

• Vitamin D is a potent immunomodulator, influencing both your innate and adaptive immune responses. As such, vitamin D deficiency has been linked to health conditions such as osteoporosis, autoimmune diseases, cardiovascular diseases and cancer
• Vitamin D is also crucial for the maintenance of healthy bones and nervous system function
• Sun exposure is the primary source of vitamin D, and while sunburn needs to be avoided, this risk needs to be balanced with the need for vitamin D production
• In the critically ill, vitamin D deficiency has been shown to increase infection and mortality rates, and is associated with longer hospital stays
• Chinese researchers concluded that vitamin D status can predict your risk of death from COVID-19, as well as the severity of your symptoms in the acute phase. Having a vitamin D level lower than 36.04 ng/mL was predictive for death