ROCHESTER - Vitamin D deficiency may contribute to a higher number of heart and stroke-related deaths among black Americans compared to whites, according to a University of Rochester Medical Center study.
The journal Annals of Family Medicine is publishing the study in the January-February edition, which goes online Jan. 11, 2010.
Researchers sought to understand the well-documented disparity between blacks and whites in cardiovascular deaths. They turned to vitamin D because growing evidence links low serum levels of D to many serious illnesses including diabetes, hypertension, kidney and heart disease.
Lead author KevinFiscella, M.D., said a complex host of genetic and lifestyle factors among blacks may explain why this population group has lower vitamin D levels across the lifespan than other races.
People get vitamin D through their diets, sun exposure, and oral supplements. Genetic factors common to blacks sometimes preclude vitamin D absorption, such as a higher incidence of lactose intolerance, which can eliminate vitamin-D fortified milk from the diet, and darker skin pigment that significantly reduces vitamin D synthesis.
“Therefore, our study suggests that the next step would be to intervene to boost vitamin D levels safely, with supplements,” said Fiscella, a national expert on disparities in health care and a professor of Family Medicine and Community and Preventive Medicine at URMC.
With funding through the National Heart Lung and Blood Institute, Fiscella and colleagues studied a sample of more than 15,000 American adults. The data included measurements of blood levels of vitamin D and death rates due to cardiovascular disease. Researchers also looked at other factors that contribute to heart health, such as body mass index, smoking status and levels of C-reactive protein.
Overall, the analysis showed that, as expected, a vitamin D deficiency was associated with higher rates of death among all people in the sample. In fact, those adults with the worst deficiency had a 40 percent higher risk of death from cardiac illness. This suggests that vitamin D may be a modifiable, independent risk factor for heart disease, Fiscella said.
Most striking, however, was that when researchers adjusted the statistics to look at race, blacks had a 38 percent higher risk of death than whites. As vitamin D levels rose, however, the risk of death was reduced. The same was true when researchers analyzed the effect of poverty on cardiovascular death rates among blacks, which suggests that vitamin D deficiency and poverty each exert separate risk factors, the study said.
A review article published in September 2009 in The American Journal of Medicine, noted that Vitamin D deficiency is a worldwide health problem. In the U.S., inadequate Vitamin D has been reported in about 36 percent of otherwise healthy young adults and about 57 percent of general medicine hospitalized patients.
Vitamin D is metabolized in the liver and converted to 25 hydroxyvitamin D or 25(OH) D, the form used to determine a person’s status through a blood test. Deficiency is usually defined by levels of less than 20 nanograms per milliliter; 30 ng/ml is viewed as sufficient. The mean blood level in the study sample was 29.5 ng/ml.
Most of the body’s tissues and cells have vitamin D receptors, making it a potent regulator of cell activity and growth. A deficiency contributes to inflammation associated with heart disease, many cancers and poor bone health.
Fiscella cautions, however, that not all observational studies of vitamin deficiency are borne out by subsequent clinical trials. For example, previous observational studies of vitamin E and beta-carotene that were associated with poor heart health did not hold up in later clinical studies. The need to further assess the vitamin D connection to heart disease is convincing, however, particularly among blacks, he added.
Other at-risk people include the obese and the elderly, (particularly housebound or nursing home residents), because vitamin D levels decline with age. And although more sun exposure can boost levels of D, skin cancer is also an increasing risk to many people. Therefore, medical authorities usually recommend increased dietary intake and/or supplementation as the best way to correct a deficiency.
BEVERLY HILLS - Quality vitamins for women should perform important functions such as slowing the aging process, strengthening the immune system, increasing energy levels and supporting the balancing of the female hormones.
When considering which daily vitamins for women to take, keep in mind that the least costly ingredients are the vitamins and minerals. A woman’s body also needs a variety of anti-aging natural substances that are proven by clinical studies to provide specific health benefits.
Taking a high-quality anti-aging daily supplement helps fill in the dietary gaps that every woman will have. What woman really consumes the recommended 5-9 daily servings of vegetables and fruits each day? It’s difficult for anyone to do…
For example, your body will use nutrients such as amino acids, antioxidants, bioflavanoids, neuronutrients, enzymes and specialized substances such as L-Carnosine, alpha lipoic acid, acetyl L-Carnitine and so on.
And women have the need for certain nutrients that are different than men, nutrients that help support the balancing of the female hormones so necessary for good health.
Every woman in her 30’s and over MUST be providing her body with certain nutrients to be healthy. And taking one-a-day drugstore or supermarket vitamins for women is probably a waste of time and money.
Today’s women have special concerns when looking to find vitamins for women that help provide needed protection from illness.
For example, osteoporosis affects a large percentage of older women, and this condition typically begins in a woman’s 30’s. Daily dietary calcium and magnesium supplementation along with other nutrients that assist in absorption should be considered essential for any woman over 40.
Heart health has to be considered vital for a woman as she ages - and essential fatty acids are needed on a regular basis for a healthy heart. The need for women to have a healthy dietary balance of the Omega-3 and Omega-6 fatty acids is well-documented in clinical trials.
Breast health and reproductive system health must be considered a high priority for today’s woman. Providing your body with nutrients that support the body’s immune system function and healthy tissue is essential when looking to find vitamins for women. These vitamins for women will provide the nutrients essential for good health.
Vitamin B3 is one of 8 B vitamins. It is also known as niacin (nicotinic acid) and has 2 other forms, niacinamide (nicotinamide) and inositol hexanicotinate, which have different effects from niacin.
All B vitamins help the body to convert food (carbohydrates) into fuel (glucose), which is “burned” to produce energy. These B vitamins, often referred to as B complex vitamins, also help the body metabolize fats and protein. B complex vitamins are necessary for healthy skin, hair, eyes, and liver. They also help the nervous system function properly.
Niacin also helps the body make various sex and stress-related hormones in the adrenal glands and other parts of the body. Niacin is effective in improving circulation and reducing cholesterol levels in the blood.
All the B vitamins are water-soluble, meaning that the body does not store them.
The body’s needs for B3 can usually be met through diet; it is rare for anyone in the developed world to have a B3 deficiency. In the United States alcoholism is the prime cause of vitamin B3 deficiency.
Symptoms of mild deficiency include indigestion, fatigue, canker sores, vomiting, and depression. Severe deficiency can cause a condition known as pellagra. Pellagra is characterized by cracked, scaly skin, dementia, and diarrhea. It is generally treated with a nutritionally balanced diet and niacin supplements. Niacin deficiency also results in burning in the mouth and a swollen, bright red tongue
Very high doses of B3 (available by prescription) have been shown to prevent or improve symptoms of the following conditions. However, taken at high doses niacin can be toxic, so you should take doses higher than the Recommended Daily Allowance only under your doctor’s supervision. Researchers are trying to determine if inositol hexanicotinate has similar benefits without serious side effects, but so far results are preliminary.
High Cholesterol
Niacin (but not niacinamide) has been used since the 1950s to lower elevated LDL (”bad”) cholesterol and triglyceride (fat) levels in the blood and is more effective in increasing HDL (”good”) cholesterol levels than other cholesterol-lowering medications. However, side effects can be unpleasant and even dangerous. High doses of niacin cause flushing of the skin (which can be reduced by taking aspirin 30 minutes before the niacin), stomach upset (which usually subsides in a few weeks), headache, dizziness, and blurred vision. There is an increased risk of liver damage. A time-release form of niacin reduces flushing, but its long-term use is associated with liver damage. In addition, niacin can interact with other cholesterol-lowering drugs (see “Possible Interactions”). You should not take niacin at high doses without your doctor’s supervision.
Atherosclerosis
Because niacin lowers LDL and triglycerides in the blood, it may help prevent atherosclerosis (hardening of the arteries) and is sometimes prescribed along with other medications. However, niacin also increases levels of homocysteine levels in the blood, which is associated with an increased risk of heart disease. This is another reason you should not take high doses of niacin without your doctor’s supervision.
Diabetes
Some evidence suggests that niacinamide (but not niacin) might help delay the onset of insulin dependence (in other words, delay the time that you would need to take insulin) in type 1 diabetes. In type 1 diabetes, the body’s immune system mistakenly attacks the cells in the pancreas that make insulin, eventually destroying them. Niacinamide may help protect those cells for a time, but more research is needed to tell for sure.
The effect of niacin on type 2 diabetes is more complicated. People with type 2 diabetes often have high levels of fats and cholesterol in the blood, and niacin, often in conjunction with other drugs, can lower those levels. However, niacin can also raise blood sugar levels, resulting in hyperglycemia — particularly dangerous for someone with diabetes. For that reason, anyone with diabetes should take niacin only when directed to do so by their doctor, and should be carefully monitored for hyperglycemia.
Osteoarthritis
One preliminary study suggested that niacinamide may improve arthritis symptoms, including increasing joint mobility and reducing the amount of nonsteroidal anti-inflammatory drugs (NSAIDs) needed. But more research is needed to determine whether there is any real benefit.
Alzheimer’s disease
Population studies show that people who get higher levels of niacin in their diet have a lower risk of Alzheimer’s disease. No studies have evaluated niacin supplements, however.
Skin conditions
Topical forms of niacin are being studied as treatments for acne, aging, and prevention of skin cancer, although results are too early to know whether it is effective.
Dietary Sources:
The best dietary sources of vitamin B3 are found in beets, brewer’s yeast, beef liver, beef kidney, fish, salmon, swordfish, tuna, sunflower seeds, and peanuts. Bread and cereals are usually fortified with niacin. In addition, foods that contain tryptophan, an amino acid the body coverts into niacin, include poultry, red meat, eggs, and dairy products.
Available Forms:
Vitamin B3 is available in several different supplement forms: niacinamide, niacin, and inositol hexaniacinate. Niacin is available as a tablet or capsule in both regular and timed-release forms. The timed-release tablets and capsules may have fewer side effects than the regular niacin; however, the timed-release versions are more likely to cause liver damage. Regardless of the form of niacin being used, periodic checking of liver function tests is recommended when high doses (above 100 mg per day) of niacin are used.
How to Take It:
Daily recommendations for niacin in the diet of healthy individuals are listed below.
Generally, high doses of niacin are used to control specific diseases, such as high cholesterol. Such high doses are considered “pharmacologic” and must be prescribed by a doctor, who will have you increase the amount of niacin slowly, over the course of 4 - 6 weeks, and take the medicine with meals to avoid stomach irritation.
Pediatric
* Infants birth to 6 months: 2 mg (adequate intake)
Because of the potential for side effects and interactions with medications, you should take dietary supplements only under the supervision of a knowledgeable health care provider.
High doses (50 mg or more) of niacin can cause side effects. The most common side effect is called “niacin flush,” which is a burning, tingling sensation in the face and chest, and red or “flushed” skin. Taking an aspirin 30 minutes prior to the niacin may help reduce this symptom.
At the very high doses used to lower cholesterol and treat other conditions, liver damage and stomach ulcers can occur. Your health care provider will periodically check your liver function through a blood test.
People with a history of liver disease or stomach ulcers should not take niacin supplements. Those with diabetes or gallbladder disease should do so only under the close supervision of their doctor.
Niacin should not be used if you have gout.
Taking any one of the B complex vitamins for a long period of time can result in an imbalance of other important B vitamins. For this reason, it is generally important to take a B complex vitamin with any single B vitamin.
Possible Interactions:
If you are currently being treated with any of the following medications, you should not use niacin without first talking to your healthcare provider.
Antibiotics, Tetracycline — Niacin should not be taken at the same time as the antibiotic tetracycline because it interferes with the absorption and effectiveness of this medication. (All vitamin B complex supplements act in this way and should therefore be taken at different times from tetracycline.)
Aspirin — Taking aspirin before taking niacin may reduce flushing associated with this vitamin, but should only be done under your doctor’s supervision.
Anticoagulants (blood thinners) — Niacin may make the effects of these medications stronger, increasing the risk of bleeding.
Blood Pressure Medications, Alpha-blockers — Niacin can make the effects of medications taken to lower blood pressure stronger, leading to the risk of low blood pressure.
Cholesterol-lowering Medications — Niacin binds bile-acid sequestrants (cholesterol-lowering medications such as colestipol, colesevelam, and cholestyramine) and may decrease their effectiveness. For this reason, niacin and these medications should be taken at different times of the day.
Recent scientific evidence suggests that taking niacin with simvastatin (a drug that belongs to a class of cholesterol-lowering medications known as HMG-CoA reductase inhibitors, or statins), appears to slow down the progression of heart disease. However, the combination may also increase the likelihood for serious side effects, such as muscle inflammation or liver damage.
Diabetes Medications — Niacin may increase blood glucose (sugar) levels. People taking insulin, metformin, glyburide, glipizide, or other medications used to treat high blood sugar levels should monitor their blood sugar levels closely when taking niacin supplements.
Isoniazid (INH) — INH, a medication used to treat tuberculosis, may lower levels of niacin in the body and cause a deficiency.
Nicotine Patches — Using nicotine patches with niacin may worsen or increase the risk of flushing associated with niacin.
