Another, Dec 2004, Report on Vitamin D

[Guest guest]

Hi folks:

This seems pretty unequivocal. Assuming the reports like this one

and others are correct, it seems anyone who is not supplementing with

vitamin D3 is nutz!

" Sunlight and vitamin D for bone health and prevention of autoimmune

diseases, cancers, and cardiovascular disease.

Holick MF.

Department of Medicine, Section of Endocrinology, Nutrition, and

Diabetes, Vitamin D, Skin, and Bone Research Laboratory, Boston

University Medical Center, Boston, MA 02118, USA. mfholick@...

Most humans depend on sun exposure to satisfy their requirements for

vitamin D. Solar ultraviolet B photons are absorbed by 7-

dehydrocholesterol in the skin, leading to its transformation to

previtamin D3, which is rapidly converted to vitamin D3.

Season, latitude, time of day, skin pigmentation, aging, sunscreen

use, and glass all influence the cutaneous production of vitamin D3.

Once formed, vitamin D3 is metabolized in the liver to 25-

hydroxyvitamin D3 and then in the kidney to its biologically active

form, 1,25-dihydroxyvitamin D3.

Vitamin D deficiency is an unrecognized epidemic among both children

and adults in the United States. Vitamin D deficiency not only causes

rickets among children but also precipitates and exacerbates

osteoporosis among adults and causes the painful bone disease

osteomalacia. Vitamin D deficiency has been associated with increased

risks of deadly cancers, cardiovascular disease, multiple sclerosis,

rheumatoid arthritis, and type 1 diabetes mellitus.

Maintaining blood concentrations of 25-hydroxyvitamin D above 80

nmol/L (approximately 30 ng/mL) not only is important for maximizing

intestinal calcium absorption but also may be important for providing

the extrarenal 1alpha-hydroxylase that is present in most tissues to

produce 1,25-dihydroxyvitamin D3.

Although chronic excessive exposure to sunlight increases the risk of

nonmelanoma skin cancer, the avoidance of all direct sun exposure

increases the risk of vitamin D deficiency, which can have serious

consequences. Monitoring serum 25-hydroxyvitamin D concentrations

yearly should help reveal vitamin D deficiencies. Sensible sun

exposure (usually 5-10 min of exposure of the arms and legs or the

hands, arms, and face, 2 or 3 times per week) and increased dietary

and supplemental vitamin D intakes are reasonable approaches to

guarantee vitamin D sufficiency.

PMID: 15585788 [PubMed - in process] "