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Vitamin D and Heart Disease

Research suggests that low levels of vitamin D may contribute to or be a cause of syndrome X with associated hypertension, obesity, diabetes and heart disease.50 Vitamin D regulates vitamin-D-binding proteins and some calcium-binding proteins, which are responsible for carrying calcium to the "right location" and protecting cells from damage by free calcium.51

Thus, high dietary levels of calcium, when D is insufficient, may contribute to calcification of the arteries, joints, kidney and perhaps even the brain.52-54

Many researchers have postulated that vitamin D deficiency leads to the deposition of calcium in the arteries and hence atherosclerosis, noting that northern countries have higher levels of cardiovascular disease and that more heart attacks occur in winter months.55-56

Scottish researchers found that calcium levels in the hair inversely correlated with arterial calcium-the more calcium or plaque in the arteries, the less calcium in the hair.

Ninety percent of men experiencing myocardial infarction had low hair calcium. When vitamin D was administered, the amount of calcium in the beard went up and this rise continued as long as vitamin D was consumed. Almost immediately after stopping supplementation, however, beard calcium fell to pre-supplement levels.27

Administration of dietary vitamin D or UV-B treatment has been shown to lower blood pressure, restore insulin sensitivity and lower cholesterol.58-60

The Battle of the Bulge

Did you ever wonder why some people can eat all they want and not get fat, while others are constantly battling extra pounds? The answer may have to do with vitamin D and calcium status.

Sunlight, UV-B, and vitamin D normalize food intake and normalize blood sugar.

Weight normalization is associated with higher levels of vitamin D and adequate calcium.61 Obesity is associated with vitamin-D deficiency.62-64 In fact, obese persons have impaired production of UV-B-stimulated D and impaired absorption of food source and supplemental D.65

When the diet lacks calcium, whether from D or calcium deficiency, there is an increase in fatty acid synthase, an enzyme that converts calories into fat. Higher levels of calcium with adequate vitamin D inhibit fatty acid synthase while diets low in calcium increase fatty acid synthase by as much as five-fold.

In one study, genetically obese rats lost 60 percent of their body fat in six weeks on a diet that had moderate calorie reduction but was high in calcium. All rats supplemented with calcium showed increased body temperature indicating a shift from calorie storage to calorie burning (thermogenesis).61

The Right Fats

The assimilation and utilization of vitamin D is influenced by the kinds of fats we consume. Increasing levels of both polyunsaturated and monounsaturated fatty acids in the diet decrease the binding of vitamin D to D-binding proteins. Saturated fats, the kind found in butter, tallow and coconut oil, do not have this effect.

Nor do the omega-3 fats.66 D-binding proteins are key to local and peripheral actions of vitamin D. This is an important consideration as Americans have dramatically increased their intake of polyunsaturated oils (from commercial vegetable oils) and monounsaturated oils (from olive oil and canola oil) and decreased their intake of saturated fats over the past 100 years.

In traditional diets, saturated fats supplied varying amounts of vitamin D. Thus, both reduction of saturated fats and increase of polyunsaturated and monounsaturated fats contribute to the current widespread D deficiency.

Trans fatty acids, found in margarine and shortenings used in most commercial baked goods, should always be avoided. There is evidence that these fats can interfere with the enzyme systems the body uses to convert vitamin D in the liver.80

The Many Forms of Vitamin D

There are two types of vitamin D found in nature. Vitamin D2 is formed by the action of UV-B on the plant precursor ergosterol. It is found in plants and in was formerly added to irradiated cows milk. Most milk today contains D3. Vitamin D3 or cholecalciferol is found in animal foods. Both forms of vitamin D have been used successfully to treat rickets and other diseases related to vitamin D insufficiency.

Many consider D3 the preferred vitamin, having more biologic activity. Vitamin D3 as found in food or in human skin always comes with various metabolites or isomers that may have biological benefit.

Dr. Price believed that there were as many as 12 metabolites or isomers in the vitamin D found in animal foods. When vitamin D is taken in the form of fish oil, or eaten in foods such as eggs or fish, these metabolites will be present. Both D2 and D3 can be toxic when taken inappropriately in large amounts.

When humans take in vitamin D from food or sunlight, it is converted first in the liver to the form 25(OH)D and then in the kidney to 1,25(OH)D. These active forms of vitamin D are available by prescription and are given to patients with liver or kidney failure or those with an hereditary metabolic defect in vitamin-D conversion.

Vitamin D Therapy

In my clinical practice, I test for vitamin-D status first. If D is needed, I try to combine sunlight exposure with vitamin D and mineral supplements.
Single, infrequent, intense, skin exposure to UV-B light not only causes sunburn but also suppresses the immune system. On the other hand, frequent low-level exposure normalizes immune function, enhancing NK-cell and T-cell production, reducing abnormal inflammatory responses typical of autoimmune disorders, and reducing occurrences of infectious disease.26;67;68-71

Thus it is important to sunbathe frequently for short periods of time, when UV-B is present, rather than spend long hours in the sun at infrequent intervals. Adequate UV-B exposure and vitamin-D production can be achieved in less time than it takes to cause any redness in the skin.

It is never necessary to burn or tan to obtain sufficient vitamin D.

If sunlight is not available in your area because of latitude or season, sunlamps made by Sperti can be used to provide a natural balance of UV-B and UV-A. Used according to instructions, these lamps provide a safe equivalent of sunlight and will not cause burning or even heavy tanning.

Tanning beds, on the other hand, are not acceptable as a means of getting your daily dose of vitamin D because they provide high levels of UV-A and very little UV-B.

If you have symptoms of vitamin-D insufficiency or are unable to spend time in the sun, due to season or lifestyle or prior skin cancer, consider adding a supplement of 1,000 IU daily. Higher levels may be needed but should be recommended and monitored by your health care practitioner after testing serum 25(OH)D. 1,000 iu can be obtained from a concentrated supplement or from 2 teaspoons of high quality cod liver oil.

Both Carlson Labs and Solgar make a 1,000 IU vitamin-D supplement naturally derived from fish oil. (Do not attempt to obtain large amounts of vitamin D from cod liver oil alone, as this would supply vitamin A in excessive and possibly toxic amounts.)

Supplementation is safe as long as sarcoidosis, liver or kidney disease is not present and the diet contains adequate calcium, magnesium and other minerals.

Adequate calcium and magnesium, as well as other minerals, are critical parts of vitamin D therapy. Without calcium and magnesium in sufficient quantities, vitamin-D supplementation will withdraw calcium from the bone and will allow the uptake of toxic minerals.

Do not supplement vitamin D and do not sunbathe unless you are sure you have sufficient calcium and magnesium to meet your daily needs. Weston Price suggested a minimum of 1,200-2,400 mg of calcium daily. Research suggests that 1,200-1,500 mg is adequate as a supplement for most adults, both men and women. (Magnesium intake should be half that of calcium.)

Two excellent sources of calcium in the human diet are -dairy products and bone broths.2 If the diet does not contain sufficient amounts, you will need to add supplements. Bone meal, dolomite powder or calcium and magnesium tablets (Solgar or Kal), or calcium carbonate or lactate (Solgar, Kal, Now or Twinlab) are good calcium sources, inexpensive and safe.74 All of these brands have been tested and found to be free of lead and other heavy metals.

In my experience, the forms of calcium given in supplements should be equivalent to those found in food-bone meal as in the broth, calcium lactate as in milk products and dolomite as in lime used to process cornmeal products. These forms work most efficiently and with the least cost for bone repletion and general repletion of serum calcium status.75 If your diet is high in protein, calcium lactate or carbonate is probably a better source of calcium.

Read the label carefully to see how much elemental calcium is contained in each dose or tablet and make sure to take the right amount. If the label says a serving size is three tablets and contains 1,000 mg of calcium, you must take the full serving size to get that amount.

Higher amounts of calcium are important for anyone diagnosed with bone loss. Total daily calcium as a supplement may range from 1,500 mg to 2,000 mg depending on current bone status and your body size. Make the effort to split up your daily dose. Do not take all your calcium and magnesium once a day. A higher percentage of the calcium dose is absorbed if delivered in smaller, more frequent amounts.82

Expensive "chelated" calciums are not necessary if vitamin-D status is adequate. Taking calcium without sufficient D may cause other problems. Vitamin D controls the production of some calcium binding proteins, which are critical to normal calcium utilization.

Patients on vitamin-D therapy report a wide range of beneficial results including increased energy and strength, resolution of hormonal problems, weight loss, an end to sugar cravings, blood sugar normalization and improvement of nervous system disorders.

A paradoxical transient and non-complicating hypercalciuria (more calcium in the urine) may occur when the program is first initiated. This resolves quickly when adequate calcium and other minerals are consumed.

Two other temporary side effects may occur during the first several months of treatment. One is daytime sleepiness after calcium is taken. This usually resolves itself after about one week. The other condition is the reappearance of pain and discomfort at the site of old injuries, a sign of injury remodeling or proper healing, which may take some time to clear up.

Assessing Vitamin D Status

Blood Testing: Currently there are two tests available for physicians to assess vitamin-D status. One is for the somewhat biologically active precursor 25(OH)D and another for 1,25(OH)D, the most active form, which is converted in the kidney and other organs.

The latter is often normal in the blood even when the precursor 25(OH)D is low or deficient. The precursor is a better marker of vitamin-D status (or reserves) than the most active 1,25(OH)D form. It is the optimum level of 25(OH)D that is most strongly associated with general good health. (The test values given in this article are for 25(OH)D.)

For many years the acceptable level of 25(OH)D has been at least 9 ng/ml (23 nmol/l). Some researchers believe that 20 ng/ml (50 nmol/l) should be the lower acceptable limit72 but Dr. Vieth presents a large amount of data to support his claim that this is far from optimal.3

Optimal levels are certainly at least 32 ng/ml (80 nmol/l) and preferably closer to 40 ng/ml (100 nmol/l).

Salivary pH Testing for calcium sufficiency: A method of assessing ionized calcium levels has been used by Weston Price, DDS and Carl Reich, MD and has confirmation in current research.73 After determining your serum-D status (testing) and undertaking a program of supplementation with vitamin D, calcium and magnesium, morning salivary pH should read 6.8-7.2.

Lower values may indicate insufficient vitamin D (retest), or low levels of calcium in the diet. Look for pH paper with a range of 5.5-8.0 and increments of 0.2. PH papers with 0.5-degree increments are not sensitive enough to monitor progress. (Note: Do not take more than 1,000 IU of vitamin D without testing and supervision by a knowledgeable healthcare practitioner.

Calcium can be adjusted within the ranges suggested. Several months of supplementation may be required to show positive results if the deficiency is severe and prolonged.)

Toxicity Issues

Vitamin programs usually omit vitamin D because of concerns about toxicity. These concerns are valid because vitamin D in all forms can be toxic in pharmacological (drug-like) doses. The dangers of toxicity have not been exaggerated, but the doses needed to result in toxicity have been ill defined with the unfortunate result that many people currently suffer from vitamin-D deficiency or insufficiency.

Abnormally high levels of vitamin D are indicated by blood levels exceeding 65 ng/ml or 162 nmol/l for extended periods of time and may be associated with chronic toxicity.

Levels of 200-300 nmol/l or higher have been seen in several studies using supplementation and quickly resolve when supplementation is stopped. In such cases no long-term problems have been found. Long-term supplementation, without monitoring, may have serious consequences.

Before 1993, there was no affordable and available blood test for vitamin D. Now there is. To avoid problems, anyone engaging in levels of vitamin-D supplementation above 1,000 iu daily should have periodic blood tests. Don't forget to calculate your total vitamin-D intake from all sources-sunlight, food (including vitamin D in milk) and supplements, including cod liver oil.

Dr. Vieth suggests that critical toxicity may occur at doses of 20,000 IU daily and that the Upper Limit (UL) of safety be set at 10,000 IU, rather than the current 2,000 IU.

While this may or may not be the definitive marker for safety in healthy persons with no active liver or kidney disease, there is no clinical evidence that long-term supplementation needs to be greater than 4,000 IU for optimal daily maintenance. This level would be somewhat lower when combined with exposure to UV-B.3;76

Doses used in clinical studies range from as little as 400 IU daily to 10,000-500,000 IU, given either as a single onetime dose or daily, weekly or monthly. Such large doses are given either as a prophylactic or because compliance is considered a problem.

There seems to be some evidence that vitamin D works better, without toxicity, when given in lower, more physiologic doses of 2,000-4,000 IU daily rather than as 100,000 IU once a month. However, a single monthly dose of 100,000 IU did replete low levels of vitamin D in adolescents during winter.77

In my experience and that of other researchers, high, infrequent dosing can lead to problems. In one recent study, blood levels rose from low to extremely high, (more than 300 nmol/l) 2 to 4 hours after a 50,000 IU oral dose,65 and then slowly returned to pretreatment suboptimal levels. Clearly this must disrupt normal feedback mechanisms in D and calcium regulation.

Vitamin A can be administered in large, infrequent doses from consumption of animal or fish liver (or injections, used in third world countries to prevent blindness) because we have storage capacity for vitamin A in our livers. Vitamin D is different.

It has only a small storage pool in the liver and peripheral fat. Our ancestors most definitely did not get vitamin D in large, infrequent doses. While vitamin D is stored in body fat, storage is not sufficient to maintain optimum blood levels during winter months.78

A single exposure to UV-B light will raise levels of vitamin D over the next 24 hours and then return to baseline or slightly higher within 7 days. Historically our requirements for D were satisfied by daily exposure to sunlight and/or daily intake from food. Lowfat diets and lack of seafood in the diet further contribute to the current worldwide insufficiency of vitamin D.

Sunlight on the Inside

If any nutrient incorporates the properties of sunlight, it is vitamin D. The healthy "primitive" peoples that Dr. Price observed not only had broad, round, "sunny" faces, they also had sunny dispositions and optimistic attitudes towards life in spite of many hardships.

Typical food intakes for peoples who have not been "civilized" range from 3,000 IU-6,000 IU. Modern intakes are paltry in comparison. The standard American diet provides vitamin D only in very low quantities.

The first step towards redressing some of the ills of civilized life-from depression to road rage, from cavities to osteoporosis-would be to get more light, inside or outside. Vitamin D adds sunlight to life from childhood through the golden years. In nonagenarians and centagenarians high levels of vitamin D in the blood and normal thyroid function were the strongest markers of health and longevity.79

Whether in the form of sunlight or dietary vitamin D from food and fish oils, optimal levels of the sunshine vitamin allow your body and mind to thrive, even during periods of stress.

Vitamin D Actions

The action of vitamin D, whether from food, supplements or sunlight conversion, is that of a "pro-hormone," rather than of a vitamin.
According to the dictionaries, a hormone is a substance, usually a peptide or steroid, produced by one tissue and conveyed by the bloodstream to another. Hormones affect physiological activity, such as growth or metabolism.

More generally, a hormone is one of various similar substances found in plants and insects that regulate development. By contrast, vitamins are various fat-soluble or water-soluble organic substances essential in minute amounts for normal growth and activity of the body. They are obtained naturally from plant and animal foods.

Hormones are powerful regulators that can have both good and bad effects. With progesterone, DHEA, estrogen, thyroid or any other hormone, including vitamin D, there can be a profound cellular response when levels are altered by supplementation. Vitamins and minerals are elements used by the body to make enzymes, bone, immune fractions and other substances in the human body, but they are not regulators.

As a pro-hormone, vitamin D can be dangerous because too much has the potential for great harm as does too little. That is why testing is important for those on vitamin-D therapy.

When you take thyroid hormones, you are instructed to test first and retest to make sure the amount you are taking is correct. So, too, with vitamin D. The rule is test, treat (if necessary) and retest until you find the right amount to meet your daily need.

According to our current levels of knowledge, there are no obvious symptoms of vitamin D overdose until the overdose is nonreversible. Testing can alert us not only to deficiency but also toxicity. Fortunately, we now have tests for vitamin D status that are not expensive.

Testing Vitamin D Level Is Important

In my practice, I am discovering that some people may need upwards of 4,000 IU daily to maintain optimal blood levels. Others may find that anything over 200-400 IU puts them in a situation of overdose. This is a problem of genetics.

Some people utilize vitamin D better than others. Before the days of travel and great population migrations, the process of natural selection created population groups that best responded to the levels of vitamin D available through exposure to sunlight and in the diet. Migration, immigration and intermarriage make it impossible to determine needs without testing.

Once you test and determine the level of D from sunlight, food and supplements that maintains optimum levels of vitamin D in your blood, then you know the "dose" that you will need as long as you live at that altitude and latitude. You should test twice a year as in many locations the need for D may vary greatly from summer to winter.

Krispin Sullivan, CN is a researcher and clinical nutritionist in practice in Woodacre, California. She is currently working on a book, Naked at Noon: The Importance of Sunlight and Vitamin D, to be published in 2001.

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Sources

UV-B Meter: Sunsor, Inc. (800) 492-9815 Sunsor

pH Testing Papers: Pike Agri-Lab Supplies (207) 684-5131 or info@pikeagri.com

Carlson Labs Vitamin D: (888) 880-3055 www.vitaminshoppe.com

Solgar Vitamin D: L & H Vitamins (800) 221-1152

Sperti Sunlamps: (800) 544-3757 www.sperti.com

http://www.westonaprice.org/nutrition_guidelines/nutrition_vitaminD.html

http://www.sunlightandvitamind.com