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[Guest guest]

, This might be helpful, I found it interesting. Neil

http://www.encyclopedia.com/doc/1G1-116179934.html

" Vitamin D: its role in autoimmune disease and hypertension.

From: Townsend Letter for Doctors and Patients | Date: 5/1/2004 |

Author: , V.

Townsend Letter for Doctors and Patients

We were all taught in school that Vitamin D deficiency had been wiped

out in the 1920s and 30s. That simply isn't so: Vitamin D deficiency

and insufficiency has made a roaring comeback, and made much worse by

the mostly-irrational but commercially lucrative sunscreen craze.

According to a new book (The UV Advantage) by Holick, MD, PhD,

(Professor of Medicine, Dermatology, Biophysics and Physiology at

Boston University) some of the conditions vitamin D plays a key role

in preventing--osteoporosis, prostate, breast and 11 other

cancers--have increased dramatically due to vitamin D insufficiency.

And it's not just cancer and osteoporosis: hypertension, diabetes,

cardiovascular disease, multiple sclerosis, rheumatoid arthritis,

chronic pain and inflammatory bowel disease are also on Professor

Holick's list. Unfortunately, some of the things the " experts " have

been telling us to do for years (in the name of good health and, of

course, safety) have actually made the situation much worse.

When many people think of vitamin D, they automatically think cow's

milk. The food industry added the vitamin to milk years ago: It was a

cheap way to " protect " the public from deficiency. But it's just not

working. Besides, there are so many health problems linked to cow's

milk that it's the last thing any of us should recommend anyway.

Especially when the best source of vitamin D is even more widely

available. Can we say " sunshine " ? And if we can't get enough sun, as

most of us can't, there's adequate vitamin D supplementation, which is

very inexpensive.

The road to health disaster paved with " good " intentions

Hardly anyone gets enough sun. Hundreds of thousands of years ago, our

remote ancestors lived mostly in the tropics and were exposed to

strong sunlight year-round. And according to researchers, vitamin D

deficiency didn't appear to be a problem. But as people migrated away

from the equator, they got less sun. " Civilization " and urbanization

made the deficiency much worse, and vitamin D deficiency reached a

peak in the 18th and 19th centuries when people began moving in droves

from rural areas to cities, where tall buildings blocked the sunlight.

Vitamin D itself was " discovered " in the early 20th century after

generations of rickets outbreaks were traced back to extreme

deficiencies of this vitamin. But, unfortunately, instead of

emphasizing sunlight exposure--nature's major source for vitamin D in

humans--researchers, physicians, and public health " authorities " took

a wrong turn years ago and started recommending vitamin D- " fortified "

food as the major source. (Of course, food manufacturers certainly

weren't going to argue, since they would make more profit making and

recommending vitamin D-enriched food than by emphasizing sunlight

exposure.)

Suddenly, vitamin D was everywhere. The eager food industry also

started adding it to hot dogs, soda, bread, milk, and just about

anything else they could think of. The Schlitz brewing company even

added it to beer.

About this same time, sunscreen use was just getting started. Back

then, it wasn't nearly as common as it is today, but, then, people

also weren't constantly bombarded with propaganda warning of impending

death if they didn't use it or implying that it's child abuse to

slather kids with anything less than SPF 1,000!

Here's the truth about sunscreen: Even a weak one (say SPF 8) blocks

out most (at least 88%) of the sun's UVB rays--the ones that trigger

our bodies to make vitamin D. So that " all-sunscreen, all the time "

rule is actually causing vitamin D deficiency.

And those vitamin-D enriched foods don't even exist anymore to make up

for it--manufacturers stopped making them when people started worrying

about getting too much vitamin D. When you take vitamin D orally,

there's no immediate reaction if you take too much. It's possible to

take way too much vitamin D for months, even years, before symptoms of

overdose (weakness, fatigue, headache, nausea, vomiting, diarrhea)

become obvious. When the " experts " discovered that tidbit of

information, they panicked and food manufacturers scrambled to take

the extra vitamin D out of the fortified foods. Milk was virtually the

only vitamin-D fortified survivor, and, as mentioned earlier, that

definitely isn't going to solve any health problems.

So it's no wonder that vitamin D deficiency is becoming common again.

But now that we've established why vitamin D deficiency is back, let's

move on and take a look at some of the specific conditions vitamin D

can help protect you against.

One simple vitamin takes on at least three major health concerns:

Cancer, osteoporosis and probably hypertension

In the 1940s, researchers observed a higher incidence of hypertension,

colon, prostate, and breast cancers in people living in temperate

latitudes. At the time, they couldn't fully explain the connection,

but eventually they realized that temperate zones get less sunlight,

which means the people living there get less vitamin D.

Then in 1989, researchers reported that adults with higher levels

(above 20 ng/dl) of 25-hydroxyvitamin D have 50% less risk of colon

cancer. (1) Since then, numerous studies have found that vitamin D

actually inhibits the proliferation of cancerous prostate, breast,

bone, and skin cells as well.

Very recently, scientists discovered that vitamin D regulates renin

and angiotensin, which are both involved in blood pressure regulation.

(2) Certainly not all cases of hypertension are due to insufficient

vitamin D. But a significant proportion of " essential hypertension "

(hypertension of unknown cause) can probably be traced back to vitamin

D deficiency.

Autoimmune Disease: Risk of Type 1 diabetes drops by 80%

In addition to the observations on colon, breast, and prostate cancer,

researchers have also long observed that multiple sclerosis, an

autoimmune disease, is much more prevalent in " temperate latitudes "

away from the Equator. Now there's increasing evidence that cases of

other autoimmune diseases also occur more frequently in areas farther

north and south of the equator.

Additional sunlight exposure and/or vitamin D supplementation starting

in childhood may significantly reduce the risk of lupus, rheumatoid

arthritis, multiple sclerosis, and even Type 1 diabetes, which is

included in the " autoimmune " category. And just like the others,

vitamin D helps to prevent it.

In one study, researchers divided pregnant women into several groups

and reviewed the women's vitamin D intake. Several years later, the

children born to the women who supplemented with vitamin D had fewer

cases of Type 1 diabetes. (3) In a follow-up study, children were

given 2,000 IU of vitamin D daily starting at age 1. The researchers

found that the children's risk of Type 1 diabetes dropped by 80%. (4)

Psoriasis relief so effective even the medical mainstream accepts it

Psoriasis is probably vitamin D's most well-known opponent--though

most people think it's " just " sunlight that's doing the job. Well, in

a way, it is, but the " job " sunlight is actually doing is triggering

the body's vitamin D production, which helps heal psoriasis.

Topical 1,25 dihydroxyvitamin D creme also works very well for many

psoriasis patients. In fact, it's even considered a mainstream

treatment. But, if you decide to use topical vitamin D therapy for

psoriasis, make sure it's the real thing. Patent medicine companies

have developed synthetic versions that aren't really vitamin D.

Getting enough Vitamin D

So with all the research in favor of vitamin D, how can you be sure

you're getting enough--but not too much? Well, the best source of

vitamin D--sunlight--actually has two built-in " overdose indicators. "

The first is sunburn. When you start to get slightly pink, you've

reached the limit of safe vitamin D. And you're not likely to go out

in the sun again until your pinkness subsides. The body's other

built-in vitamin-D regulator is tanning. Increasing pigment in the

skin blocks the formation of vitamin D. So the more you tan, the less

vitamin D you get. With nature's preferred vitamin D " delivery system "

(sunlight) there's no chance of overdose.

What about supplements?

In temperate latitudes it's always a good idea to take vitamin D

supplements too--especially during the fall, winter, and early spring.

For the best of health and disease prevention, it's probably wisest to

take enough vitamin D supplementation to produce a " tropical latitude "

blood level of 25-hydroxy vitamin D. In non-tropical latitudes, UVB

rays don't even penetrate through the atmosphere to the Earth's

surface in late fall, winter, and early spring, so even sun-exposed

skin doesn't form much (if any) vitamin D for most of the year. In

fact, researchers have found that in wintertime, practically no

vitamin D at all is formed in sunlight exposed skin if you live north

of 35[degrees] latitude (which is about the equivalent of Los Angeles

and Charlotte, NC).

If you're nervous about taking or recommending oral vitamin D

supplements because of the possibility of overdose, there's research

guidance. Researchers studying safety limits have pointed out that

they may have been much too cautious. A few years ago, Reinhold Veith

PhD published an article re-examining the upper limits of vitamin D

safety. (5) That study concluded that the often-mentioned upper limit

of vitamin D safety, 2,000 IU daily, " is too low by at least 5-fold. "

Instead, he suggested that 10,000 IU daily might be a better " safe

upper limit. "

The same journal published a follow-up study in 2001. (6) This time,

the researchers asked 61 healthy men and women to take either 1,000 IU

or 4,000 IU of vitamin D3 (cholecalciferol) daily for two to five

months, starting in January or February. Levels of vitamin D3

increased to " high-normal " (for temperate latitudes) in nearly all

those studied. And none developed higher-than-normal serum vitamin D3

levels. The researchers concluded " 4,000 IU of vitamin D3 to be a safe

[daily] intake " for adults.

But of course the first recommendation for assuring sufficient vitamin

D is to get enough non-winter sunshine without the use of sunscreen to

make your skin turn faintly pink. At that point, get out of the sun.

Each day that you don't get enough sun to turn slightly pink, you

should take 2,000-3,000 units of vitamin D in supplement form. (For

children over 1 year of age, 400 IU daily is a minimum, 1,000 IU daily

is probably better.)

If you're past 35, it's probably a good idea to consider taking up to

4,000 IU daily to help prevent osteopenia and osteoporosis. This is

especially important if you have a family history of this problem.

Too little, too much--now vitamin D supplements come in doses " just right "

Over the counter vitamin D has been available in multi-vitamin

supplements and individual vitamin capsules for years, but only in

quantities of 200-400 IU-at most. Or you can get 50,000 IU vitamin D

capsules by prescription. But until recently, there was no middle

ground. Now, though, 1,000,2,000, and 5,000 IU capsules are available

in some natural food stores, compounding pharmacies, and through the

Tahoma Clinic Dispensary.

Although research has found these levels of oral vitamin D intake to

be safe, it's easy enough to be absolutely sure with a simple,

inexpensive blood test: Excess vitamin D causes an elevation of serum

calcium, which any doctor or lab can test for. Most labs can also test

your levels of 25-hydroxyvitamin D, or, if you're really particular

(and willing to spend more money), you can ask to be tested for the

" active " form of the vitamin, 1,25 dihydroxyvitamin D.

Whatever test you decide to take, don't let the " experts " out there

scare you out of the sun or out of the supplement aisle of your local

natural food store; they're your very best options for getting the

vitamin D your body needs.

References

1. Garland CF, Comstock GW, et al. Serum 25-hydrocyvitamin D and colon

cancer: eight-year prospective study, Lancet 1989; 2(8,673: 1,176-1,178

2. Li YC. Vitamin D regulation of the renin-angiotensin system. J Cell

Biochem 2003; 88(2): 327-331

3. Hypponen E, Laara E, Reunanen A, Jarvelin MR, Virtanen SM. Intake

of vitamin D and risk of type 1 diabetes: a birth-cohort study. Lancet

2001; 358(9,292): 1,500-1,5003

4. ibid.

5. Veith R. Vitamin D supplementation, 25-hydroxyvitamin D

concentrations, and safety. Am J Clin Nutr 1999; 69: 842-856

6. Veith R, Chan P-C R, MacFarlane G D. Efficacy and safety of vitamin

D3 intake exceeding the lowest adverse effect level. Am J Clin Nutr

2001; 71: 288-294

Could Vitamin D replace ACE inhibitors and ARBs altogether?

We may have the opportunity for the biggest advance in clinical

treatment of hypertension in decades. Very solid " basic science "

research tells us that a substantial proportion of " essential

hypertension " can be re-labeled " high-latitude hypertension, " and

successfully treated with vitamin D.

Is where you live raising your blood pressure?

As mentioned earlier, epidemiologic studies have shown that people

living near the equator are less likely to have hypertension. It's

also been observed that blood pressures tend to be higher in the

winter, when we get less sunlight, which your body uses to synthesize

vitamin D. One recent large study demonstrated a distinct connection

between increases in blood pressure and the distance people live from

the equator. (1)

Another study, published several years ago in the Lancet, reported

that ultraviolet light exposure, which increases the body's internal

vitamin D production, lowered blood pressure in individuals with mild

essential hypertension. (2) And two other small clinical trials showed

that vitamin D supplementation reduces both systolic and diastolic

blood pressure. (3,4)

Taken together, these studies and observations stongly indicate that

vitamin D is nature's leading blood pressure regulator.

Vitamin D goes one step further than ACE inhibitors--without the dangers

Vitamin D achieves its blood pressure lowering effect by addressing

one of the major causes of high blood pressure--a substance called

angiotensin II.

Angiotensin II is produced by another substance called

angiotensin-converting enzyme, or ACE. When ACE is allowed free rein,

it sometimes produces too much angiotensin II. Excess angiotensin II

constricts blood vessels, which raises blood pressure. But that's not

all that excess angiotensin II does.

Among many other bad effects, excess angiotensin II also leads to

abnormal thickening of both the heart muscle and blood vessel walls.

It increases output of adrenaline and similar substances, increases

the output of another blood pressure raising hormone called

aldosterone, and increases salt retention by the kidneys. All of this

tends to raise blood pressure.

So blocking ACE, and thereby lowering excess angiotensin II, is

actually a logical strategy for lowering blood pressure and

frequently, it works. But until recently, the best way to block ACE

was with patent medications called ACE inhibitors. ACE inhibitor names

generally end in the syllable " -pril " (enalapril, captopril, etc.),

but they're sold under trade names including Vasotec, Lotensin,

Zestril, Altace, Capoten, and others. Like most patent medications and

synthetic molecules, ACE inhibitors can cause a number of negative

side effects--cough, headache, and dizziness at best; skin rash,

kidney problems, and swelling of the face, lips, and throat at worst.

But vitamin D might be able to go one step further--without the added

disadvantages of the synthetic ACE inhibitors--by preventing the

formation of excess angiotensin II in the first place.

Here's how it works: According to a 2002 study, a tiny part of the

human genome regulates renin. Renin breaks angiotensinogen into

angiotension I. Angiotensin I is converted into angiotensin II by ACE.

Vitamin D persuades the renin-controlling gene to become less active,

(5) and the whole process slows down. The end result is less

angiotensin II and lower blood pressure.

Other researchers have found that the higher a person's serum level of

vitamin D, the lower his or her blood pressure. (6,7) And in case

studies treatment with vitamin D reduced the volunteers' plasma renin,

angiotensin II, and blood pressure. (8,9)

Vitamin D " clones " coming soon to a pharmacy near you

Of course, with all of this breakthrough news about vitamin D, patent

(pharmaceutical) medicine companies see the writing on the wall, so

they're racing to develop patentable versions of this potentially

blockbuster natural antihypertensive therapy. Right now, the

patentable versions don't have any specific fancy names--so far,

they're just referred to generally as " vitamin D analogues. "

The good news is, none of these evil twins of vitamin D has hit the

market for hypertension yet. But they're coming--as sure as you can

say " patent medicine profits. "

Fortunately, supplement companies read medical and scientific

research, too, and higher-quantity vitamin D supplements (1,000 IU,

2000 IU, and 5,000 IU) are starting to show up on the shelves of lots

of different compounding pharmacies and natural food stores or from

the Tahoma Clinic Dispensary. And, even better, these versions are

exceptionally inexpensive, with prices ranging from $7 to $9 per 100

capsules, depending on strength.

Just to put that in perspective, ACE-inhibitor prices in my area range

from $65 to $145 per 100--even for the generic versions. No wonder the

pharmaceutical companies are frantically researching patentable

" analogues. "

Safety first

It sounds like an easy solution, and it can be, but only under the

proper guidance. Please don't start recommending or taking high doses

of vitamin D to control blood pressure without proper precautions.

Since the dosage range needed to lower blood pressure isn't yet known,

and may well vary individually, it's a good idea to monitor for

vitamin D safety.

There's actually a much wider range of safe vitamin D doses than

health " authorities " generally admit. In 1999, Reinhold Veith Ph.D

published an article re-examining the upper limits of vitamin D

safety. (10) The researchers concluded that the often-mentioned upper

limit of vitamin D safety, 2,000 IU daily, " is too low by at least

5-fold. " Instead, they suggested that 10,000 IU daily might be a

better safe upper limit. The same journal published a follow-up study

in 2001 revisiting that recommendation. (11) This time, the

researchers concluded: " We consider 4,000 IU vitamin D3 to be a safe

(daily) intake " for adults.

Even so, it's smart to monitor your vitamin D intake. Back in the

1930s-1950s there were instances of massive vitamin D overdoses. When

this happens, calcium is actually leached from bones and appears in

the blood in much higher levels than normal--a condition known as

hypercalcemia. The initial signs and symptoms of hypercalcemia (and

ultimate vitamin D toxicity) consist of weakness, fatigue, headache,

nausea, vomiting, and diarrhea.

If hypercalcemia persists, calcium is then deposited in soft tissues,

most notably in the kidneys. Eventually, this can cause serious kidney

damage and osteoporosis. Head these problems off at the pass by

keeping a careful eye on your serum calcium level. Make sure to

monitor it, and if your level goes too high, decrease your vitamin D

dosage or stop taking it altogether.

If you supplement, it's wisest to monitor your serum level of

25-hydroxyvitamin D also, though this part is harder to interpret.

With supplements, levels are likely to come back as " high normal " or

" high, " but odds are that would have less to do with heading into a

danger zone than it would with misunderstandings in this country about

what " normal " vitamin D levels really are. " Normal " levels of " 1,25 D "

in American laboratories are a bit skewed, since they're determined

using data from already-deficient people in North America. And,

studies of what's " normal " almost always exclude people who take

vitamin D supplements. So your levels might come back as " high " when

they're really very normal, or even on the low side of what your body

actually needs. Remember ... an elevated serum calcium level is the

key sign that supplemental vitamin D may be in excess.

Two of the first group of 25 hydroxyvitamin D tests I requested for my

hypertensive patients came back " high. " Since both individuals had

been diagnosed with essential hypertension, both had been taking

vitamin supplements--including vitamin D, and neither had any other

problems, we decided to " proceed with caution " with the additional

vitamin D and continued to monitor their serum calcium levels closely.

Recommending and Taking Vitamin D

As always, it's best to go with nature and natural treatment first.

Get as much sunshine as you safely can! Go easy--very easy--on the

sunscreen!

Professor Holick cites epidemiological studies showing about 27,500

American women die prematurely every year from breast cancer caused by

vitamin D deficiency, many more than the 500 women who die every year

from non-melanoma skin cancer. He then calculates that 55 American

women die prematurely every year from breast cancer caused by

underexposure to sunlight for every one woman who dies prematurely

from overexposure to sunlight (non-melanoma skin cancer).

The statistics on prostate cancer and vitamin D deficiency are even

worse. Professor Holick writes, " 37,000 men die prematurely each year

from prostate cancer. It's possible to conclude that 55 to 60 men die

prematurely from underexposure to sunlight for every one that dies

prematurely due to overexposure. "

Recommend and take adequate vitamin D supplementation. Even for

healthy adults, that's 3,000-4,000 IU daily. And for children, the

diabetes-prevention studies used 1,000-2000 IU daily. Taking vitamin D

supplements is a lot more practical and cheaper than moving to

tropical latitudes!

In addition to Dr. Holick's book, written for general readers, there's

a superb website for professionals and others. Check it out at:

www.cholecalciferol-council.com

References

1. Rostand SG. Ultraviolet light may contribute to geographic and

racial blood pressure differences. Hypertension 1997; 30: 150-156

2. Krause R et al. Ultraviolet B and blood pressure. Lancet 1998; 352:

709-710

3. Pfeifer M et al. Effects of a short-term vitamin D3 and calcium

supplementation on blood pressure and parathyroid hormone levels in

elderly women. J Clin Endocrinol Metab 2001; 86: 1,633-1,637

4. Lind L et al. Reduction of blood pressure during long-term

treatment with active vitamin D (alphacalcidol) is dependent on plasma

renin activity and calcium status. A double-blind, placebo-controlled

study. Am J Hypertens 1989; 2: 20-25

5. Li YC et al. 1,25 dihydroxyvitamin D3 is a negative endocrine

regulator of the renin angiotensin system. J Clin Invest 2002: 110;

229-238

6. Kristal-Boneh E et al. Association of calcitriol and blood pressure

in normotensive men. Hypertension 1997; 30: 1,289-1,294

7. Lind L et al. Vitamin D is related to blood pressure and other

cardiovascular risk factors in middle-aged men. Am J Hypertens 1995;

2: 20-25

8. Kimura Y et al. Effectiveness of 1,25 dihydroxyvitamin D

supplementation on blood pressure reduction in a

pseudohypo-parathyroidism patient with high renin activity. Intern Med

1999; 38: 31-35

9. Park CW et al. Intravenous calcitriol regresses myocardial

hypertrophy in hemodialysis patients with secondary

hyperparathyroidism. Am J Kidney Dis 1999; 33: 73-81

10. Veith R. Vitamin D supplementation, 25-hydroxyvitamin D

concentrations, and safety. Am J Clin Nutr 1999; 69: 842-856

11. Veith R, Chan P-C R, MacFarlane G D. Efficacy and safety of

vitamin D3 intake exceeding the lowest adverse effect level. Am J Clin

Nutr 2001; 71:288-294