Originally Posted by Erika

That is a really high dose Doydie,

I'm wondering what the dose was based on. It should be determined according to your blood levels, so if you haven't had it tested lately, you may want to have that done.

There are conflicting opinions on how much D3 one should be taking, and this seems to depend on the source of the recommendation. Even scientists don't agree on how much is too much, because taking too much vitamin D can cause a number of side effects.

It would be great if we could rely on our doctors to determine the right dose for us but many of them don't keep up with current research and/or haven't looked into that research deeply enough to appreciate the potential impact of incorrect supplementation levels, drug interactions, contra-indications and the like.

The National Institutes of Health (NIH) has set the maximum upper limit at 1,000 IU daily for children to age 12 and 2,000 IU daily for adults. But some researchers believe those limits are too low.

The NIH recommended daily allowance (RDA), to prevent D3 deficiency is:

Adult
• 19 - 50 years: 5 mcg (200 IU)
• 51 - 70 years: 10 mcg (400 IU)
• 70 years and older: 15 mcg (600 IU)
• Pregnant and breast-feeding females: 5 mcg (200 IU)

The higher end for supplementing to correct deficiency is based on blood test results, but I am not familiar with the research from which it came.
They quote deficiency as being a blood level below 50 and recommend supplementing at a rate of 1000 IU D3 for every 10 points under 50.

Precautions:
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.

Side effects of D3 toxicity due to supplementation may include:
• Excessive thirst
• Metal taste in mouth
• Poor appetite
• Weight loss
• Bone pain
• Tiredness
• Sore eyes
• Itchy skin
• Vomiting
• Diarrhea
• Constipation
• A frequent need to urinate
• Muscle problems

You cannot get too much vitamin D from sunlight, and it would be very hard to get too much from food. Generally, too much vitamin D is a result of taking supplements in too high a dose.

People with the following conditions should be careful when considering taking vitamin D supplements:
• High blood calcium or phosphorus levels
• Heart problems
• Kidney disease

Possible Interactions:
If you are currently being treated with any of the following medications, you should not use vitamin D supplements without first talking to your health care provider.

Atorvastatin (Lipitor) -- Taking vitamin D may reduce the amount of Lipitor absorbed by the body, making it less effective. If you take Lipitor or any statin (drugs used to lower cholesterol), ask your doctor before taking vitamin D.

Calcium channel blockers -- Vitamin D may interfere with these medications, used to treat high blood pressure and heart conditions. If you take any of these medications, do not take vitamin D without first asking your doctor.

Calcium channel blockers include:
• Nifedipine (Procardia)
• Verapamil (Calan)
• Nicardipine (Cardene)
• Diltiasem (Cardizem, Dilacor)
• Amlodipine (Norvasc)

Corticosteroids (prednisone) -- Taking corticosteroids long-term can cause bone loss leading to osteoporosis. Supplements of calcium and vitamin D can help maintain bone strength. If you take corticosteroids for 6 months or more, ask your doctor about taking a calcium and vitamin D supplement.

Digoxin (Lanoxin) -- a medication used to treat irregular heart rhythms. Vitamin D improves absorption of calcium, and calcium, in turn, can increase the likelihood of a toxic reaction from this medication.

These drugs may raise the amount of vitamin D in the blood:
Estrogen -- Hormone replacement therapy with estrogen appears to raise vitamin D levels in the blood, which may have a positive effect on calcium and bone strength. In addition, taking vitamin D supplements along with estrogen replacement therapy (ERT) increases bone mass more than ERT alone. However, this benefit may be lost with the addition of progesterone.

Thiazide -- This kind of diuretic (water pills) can increase vitamin D activity and can lead to high calcium levels in the blood.

Vitamin D levels may be decreased by the following medications.
If you take any of these medications, ask your doctor if you need more vitamin D:

Antacids -- Taking certain antacids for long periods of time may alter the levels, metabolism, and availability of vitamin D.

Anti-seizure medications -- these medications include:
• Phenobarbital
• Phenytoin (Dilantin)
• Primidone (Mysoline)
• Valproic acid (Depakote)

Bile acid sequestrants -- used to lower cholesterol. These medications include
• Cholestyramine (Questran, Prevalite)
• Cholestipol (Colestid)

- Rifampin & Isoniazid (INH) -- medications used to treat tuberculosis.
- Mineral oil -- Mineral oil also interferes with absorption of vitamin D.
- Orlistat (Alli) -- a medication used for weight loss that prevents the absorption of fat. Because of its effect on fat, orlistat may also prevent the absorption of fat-soluble vitamins such as vitamin D. Physicians who prescribe orlistat should also add a multivitamin with fat soluble vitamins.

With love, Erika

Originally Posted by ewizabeth

I need to get my regular tests done soon so I will request they test for B12 and vit D as well. Now I'm curious about my levels.