DR. MIRKIN: Overdoses of Vitamin D Pills can Damage Your Heart
People who develop atrial fibrillation should be asked if they are taking huge doses of vitamin D.
If you have an irregular heart beat and are taking massive doses of vitamin D pills, check with your doctor immediately. This cause of irregular heartbeats can be cured by stopping the pills.
Research presented at the annual meeting of the American Heart Association on November 16, 2011 showed that having high blood levels of vitamin D triples your risk for atrial fibrillation, a condition that causes the upper part of the heart to flutter, which increases risk for forming clots that can cause strokes and can block blood flow.
I think that the optimal range for blood levels of vitamin D3 is 30 to 40 ng/dl (equal to 75 to 100 nmol/L).
In this study, those who had blood levels above 100 ng/dl (250 nmol/L) were at markedly increased risk for atrial fibrillation.
YOU CAN BE POISONED BY PILLS
You get vitamin D only from sunlight, food and pills. It is impossible to get vitamin D3 levels too high from sunlight or unfortified foods. Only pills can cause vitamin D overdoses.
WHY YOU CANNOT BE POISONED BY SUNLIGHT OR FOODS
Only a small part of the ultraviolet rays from the sun, called UVB, convert 7-dehydrocholesterol in your skin to vitamin D. Then vitamin D passes from your skin into your bloodstream. However, UVB also destroys vitamin D in the skin. This effect is so powerful that a person can never get high blood levels of vitamin D from sunlight, no matter how much sun shines on his skin.
The only foods that supply significant amounts of vitamin D are liver, fish, eggs and cod liver oil. The recommended daily intake of vitamin D for adults is 600 international units a day, and it is almost impossible to reach that amount with unfortified foods.
Vitamin D is added to milk, but only a terrible mistake in overdosing would cause vitamin D poisoning.
HOW OVERDOSES OF VITAMIN D CAUSE IRREGULAR HEART BEATS
When you take massive overdoses of vitamin D pills, blood calcium levels rise too high. Your heart beat is controlled by electricity generated by the difference between minerals inside and outside your heart.
Raising blood calcium levels too high changes the electrical currents in your heart nerves which can cause irregular heartbeats.
HOW MUCH IS SAFE?
To raise your blood levels of calcium above normal, you have to take enough vitamin D to raise your blood levels of vitamin D above 200 nmol/l (80 ng/ml). No documented cases of high blood calcium were reported following vitamin D doses less than 40,000 IU/day for up to 12 consecutive weeks (Am J Clin Nutr 1999;69: 842-856).
Therefore, there should be little concern about using the much lower dose often recommended for treatment of vitamin D deficiency (5000 IU/day).
However, we do not know how much vitamin D a person can safely take in pill form. It is my opinion that all people who take more than 3000 IU of vitamin D should have blood tests done to make sure that blood levels of vitamin D3 do not rise above 60 ng/dl (150 nmol/L).
VITAMIN D DEFICIENCY REMAINS A MAJOR CONCERN
For the past several years I have reported on the many diseases and conditions that can be caused by low vitamin D: heart disease, cancer, hypertension, arthritis, chronic pain, depression, inflammatory bowel disease, obesity, premenstrual syndrome, diabetes, muscular weakness and pain, autism, fibromyalgia, crohns disease, multiple sclerosis, autoimmune diseases and many more.
CAUSES OF VITAMIN D DEFICIENCY: DECREASED SKIN SYNTHESIS
Limited sun exposure is the main cause of vitamin D deficiency. Sunscreens and pigmentation block ultraviolet rays that stimulate your skin to make vitamin D.
Diseases in which you cannot absorb fat, such as sprue, cystic fibrosis or irritable bowel syndrome, prevent you from absorbing vitamin D.
MEDICATIONS such as anticonvulsants lower vitamin D levels.
OBESITY increases risk for Vitamin D deficiency as vitamin D is stored in fat to prevent it from circulating.
As you age, your skin is less able to make vitamin D.
THE ONLY BLOOD TEST TO DIAGNOSE VITAMIN D DEFICIENCY IS VITAMIN D3
Do not get calcitriol (1,25 dihydroxy) blood tests to diagnose low Vitamin D. Severe vitamin D deficiency causes an overactive parathyroid gland that raises the active vitamin D called calcitriol to normal.
Dr. Pinna says:
As Dr. Mirkin mentions above you need to take over 40,000 units per day to overdose on Vitamin D. Therefore, only take a small handful, or use the lower dose, 1000 instead of 5000.
Bottom Line? Take Vitamin D and don’t close your eyes!