... My vitamin D level recently tested at 10.7... Even last spring and summer where I exposed most of my body to the sun five days a week, I developed a deep tan but my vitamin D tested at 19. . . supplement or no.
An analogy, two comments and a request:
1) Lipitor supplementation causes blood level readings of Total Cholesterol to appear lower. However supplemention with Lipitor to achieve blood levels readings of Total Cholesterol <150 does NOT make us heart attack proof. Achieving blood levels readings of Total Cholesterol <150 via a whole-foods plant based diet DOES make us heart attack proof. The 150 reading in and of itself is a mere number. The significance lies in how we arrive at the number. Ingestion of cholesterol STILL damages those who supplement with Lipitor. We can use Hormone D supplemention to achieve blood level readings of >20 ng/mL but still suffer from Sunshine Deficiency.
2) Having a deep tan is not necessarily indicative of adequate blood levels of Hormone D. The first & last few hours of daylight (UV-A rays) will tan Caucasian skin, however it's the few hours encompassing solar noon (which is smack in the middle of daylight hours, i.e. an equal amount of hours/minutes from both sunrise & sunset, e.g. sunrise/set today in Upstate NY = 5:43am/8:02pm = 1:53pm SOLAR NOON) which provide what is needed to stimulate Hormone D (UV-B rays). The earlier or later a person "tans" herself from solar noon the greater the ratio of UV-A vs UV-B (that's bad - you maximize the disadvantage of sun exposure and minimize the advantage). The closer a person "tans" himself to solar noon the greater the ratio of UV-B vs UV-A (that's good - you maximize the advantage of sun exposure while minimizing the disadvantage). Optimal time today was 1:33pm-2:13pm. For more on this see Dr Alona Pulde's article http://www.savvyvegetarian.com/articles ... nswers.php
&/or buy the Lederman/Pulde book from McDougall's store. And then google images of Dr Holick, who is THE authority on Hormone D, and see a very, VERY white face devoid of any tan whatsoever, to know that Hormone D and tan skin do not correlate.
3) Blood levels of Hormone D are also dependent upon body fat levels. Optimal body fat percentage = 3%–5% in men, and 8–12% in women. How many of us know our percentage? I would guess <0.01% of us really know. Accurate testing is expensive and not covered by health insurance. Calipers and their mathematical formulas are nonsense. The best that nearly all of us readily have is simply to refer to optimal BMI levels, which = 20 to 22. (I can hear the macho conan types whining as I write this: "Oh but my BMI is high because I'm muscular" - yeah ok whatever.) Hormone D is sequestered into our fat stores to get us (those of us living in temperate latitudes) through the Winter. The more fat you have the less your Hormone D is going to show up on a blood test. Though it might show up if we analyze the globs of fat removed during an obese person's liposuction. All variables aside (e.g. race, age, height, weight, BMI, diet, exposure to sun, etc) a man's blood level of Hormone D is greater than a woman's. Everybody following me or have I lost somebody? Just lemme know if further clarification is required.
4) Now for my request. I want to ask those of you who own a Sperti light to please write about your experiences, specifically whether or not you feel investing in one was a wise decision.