Discussion: Vitamin D3 is critical for proper immune system functioning.

To prevent vitamin D3 deficiency, it is advisable to incorporate controlled sun exposure with natural foods containing vitamin D3. Vitamin D is a cholesterol derivative; its importance for the immune and hormonal systems has been known for many years.

Moderate exposure to the sun has many benefits. (Sun tanning is not the cause of skin cancer!)
Creates natural vitamin D. (Essential.)
Elevates testosterone (The male sex hormone), thus improving erection. Women do not have masculine side effects.
It helps relieve pain.
Charging the Qi energy.
It helps relaxation and improves sleep.
It promotes good moods and prevents depression.
Rejuvenates scar tissue and skin problems. (Depending on the stage).
Controlled sun exposure has additional benefits beyond vitamin D3 production.

Link:
Vitamins D3, B12, and Omega-3 are critical for proper immune function.
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