vitamin D
Firstly, vitamin D is a lipid, which means that it cannot dissolve into water and can accumulate in body fat. This means that the body cannot control the amount that is in the body. Excess vitamin D is when we become hyper calcified, brittle and have a massive heart attack.

Without prejudice.
 
Where does vitamin D come from?
Not the sun. This would be like the sun making me a new car.

Vitamin D comes from the more brittle LDL-Cholesterol. The more soft and fluid HDL-Cholesterol survives the radiation of the sun (UV light) and continues to circulate through the body where it is highly used by the brain's myelin sheath for memory and choice of thinking. The choice of thinking is where we can decide versus the nerve stimulation of pain or pleasure where we do not have a choice on the nerve sensations. Pain and pleasure are closely related but the choice is due to HDL-Cholesterol, the good one.

If HDL-Cholesterol becomes defective by becoming brittle with a double bond we need to get rid of it. This defectitive HDL-C becomes the lipid called vitamin D2, from a good lipid. The always bad lipid type of LDL-C is brittle and also smashed with UV radiation to form Vitamin D3.

Vitamin D2 and Vitamin D3 are smashed up defective lipids of the cholesterol type.

We have good cholesterol, needed for the brain, then we have bad cholesterol that is smashed up for us by the UV radiation into either D2 or D3 to be collected by the liver and emptied into the toilet.

Where we get confused.

Calcium is a mineral that is very hard, like cement or our bones. It cannot be dissolved into the water or blood plasma of the body so we need to bind it up. A lipid is best for this and hence the lipid, fat, oil, cholesterol route. Many lipids are in the body and include testosterone, estrogen and progesterone. Highly involved in muscle strength, size, shape and fertility. Lipids are necessary for life, and so is calcium. But in the right place and at the right time.

Another lipid we forget to mention is vitamin K.
 
Vitamin K has a very long tail and easily wraps into boney material and as a lipid holds calcium into the bone, also called hydroxyapatite, or simply bone meal that we used to give to dogs for healthy bones.

Vitamin K, a lipid, holds calcium in bones and teeth.
Vitamin D, a lipid, holds calcium in and around the heart and arteries.

The confusion is that vitamin D increases blood levels of calcium but does not increase calcium levels in bones. If they were to measure bones density by a biopsy, wickedly painful, it would be noted that vitamin D actually lowers calcium levels in bones.

Where do we get vitamin K.
In olden days it was from green leaves of vegetables such as lettuce in summer and boiled bones in winter to extract the lipid, oil, from the bones in winter.

What does vitamin K do?
It stops bleeding in the brain (stroke), hemorrhage, bruising and blood loss.

Notice that the Novel CoronaVirus is a hemorrhagic disease that binds to the vitamin D receptor called ACE2.

When the Covid-19 is problematic we have what appears to be a 'broken glass' image on x-ray or MRI of the lungs. This is bits of bleeding disorder from a lack of vitamin K.

Confused scientists are hence promoting vitamin D when they have forgotten the basics of lipid to calcium storage principles in medicine.
 
Harrison's: The Principles of Internal Medicine is a majorly respected text book written and edited by many over the years. A new version is often printed about every 3 years. The 14th Edition printed in 1998 is my favourite. Dr. A. Facci is a chief editor of many and works closely now with the American Government.

In my opinion, this text book has been in decline since the 14th Edition (1998) and has become confused. Harrison's used to be the 'go to' medical reference text book, however, it has changed.
 
More recently it appears that Mayo Clinic has good information about excess vitamin D.

In the blood this is called "hypervitaminosis D".
Cut and Paste from Mayo Clinic WebSite:
Vitamin D toxicity, also called hypervitaminosis D, is a rare but potentially serious condition that occurs when you have excessive amounts of vitamin D in your body. Vitamin D toxicity is usually caused by large doses of vitamin D supplements — not by diet or sun exposure.

Diet and sun exposure cannot give toxic levels of vitamin D because they cannot be in excess and do not overload as seen when we supplement and fat stores accumulate to toxic levels and the resultant calcium cements the body into leaking blood, hemorrhage and death as seen in Covid-19.

Vitamin D as a supplement accumulates in our lipids, in part why high cholesterol can be a health risk for disease and death.

Remember that the lipids of cholesterol, testosterone, LDL-C and vitamin D are all in the same family of molecules.

Without prejudice I suggest that the promotion of vitamin D to the public contributes to the death rate of Covid-19. The American and British diet has vitamin D ramped up into excess. Not seen in countries like India and China.

Next step: The thyroid controls calcium stores by mobilizing it from soft tissue, washing it in urea at the kidneys and cycles it to vitamin K. This was well described in Harrison's: The Principles of Internal Medicine 14th Edition (1998) under chapter $$999, bone remodeling, $$Author. Senior editor A. Fauci.
Archived rdid$$$ on www.reboundhealth.com. Over time this will be moved to the dot.net site.