The Recommended Dietary Allowance (RDA) of vitamin B12—or, the average daily level of intake sufficient to meet the nutrient requirements of nearly all healthy individuals—is 2.4 mcg for adult men and women. Women who are pregnant or breastfeeding should take 2.6 mcg daily and 2.8 mcg daily, respectively.
One of the best vitamins for issues of the thyroid is vitamin B12 because it plays an important role in red cell metabolism. It also increases your energy and strengthens your nervous system. Vitamin B supplements are easy to add to your everyday routine. You can find them on your local grocery or drug store shelf.
Vitamin B Is Important for Thyroid Function
It's best to take a nutritional supplement that includes the entire vitamin B complex, and you may need additional vitamin B12 if a blood test reveals your levels are low, she says.
No interactions were found between levothyroxine and Vitamin B12.
When you receive your test results, it's important to note that optimal B12 levels should be between 700-900 pg/mL. As mentioned above, most labs will not flag B12 levels unless they are under 200 pg/mL.
Supplements containing vitamins D and B along with selenium, zinc, iron, curcumin, and magnesium are among the best supplements for Hashimoto's disease. Supplements may be beneficial for some patients with this condition but should be taken with your doctor's supervision as part of a treatment plan.
Levels of 25(OH)D 30 to 32 ng/ml is considered to be sufficient, but levels of 20 to 29 ng/mL is insufficient and if it is less than 12 ng/ml is considered an evidence of severe vitamin D deficiency. Importantly, both vitamin D and thyroid hormone bind to similar receptors called steroid hormone receptors.
Avoid taking your thyroid hormone at the same time as:
Iron supplements or multivitamins containing iron. Calcium supplements. Antacids that contain aluminum, magnesium or calcium.
Iron and calcium supplements can interfere with how your body absorbs thyroid medications. So space these at least 4 hours apart. Another supplement to watch out for is biotin.
How magnesium affects the thyroid. We need magnesium to convert the inactive thyroid hormone T4 into the active thyroid hormone T3. Without this conversion, cells do not receive the more potent form of thyroid hormone. Therefore, when magnesium levels are low, our thyroid is not able to function correctly.
Too much iodine can make hypothyroidism worse in people who already have the condition. In some parts of the world, it's common for people not to get enough iodine in their diets. The addition of iodine to table salt has almost eliminated this problem in the United States.
Those who have allergies or medical conditions should always inform a doctor before receiving a vitamin B12 shot. Vitamin B12 shots may not be suitable for people with a history of: sensitivity to vitamin B12. Leber's disease, which affects the optic nerve.
Fatty foods – Fats are known to upset your body's ability to absorb thyroid replacement hormones. Fats can also prevent the thyroid's natural ability to produce hormones. Physicians recommend that you cut out all fried foods and limit your intake of fats from butter, mayonnaise and fatty meats.
High doses of vitamin B-12, such as those used to treat a deficiency, might cause: Headache. Nausea and vomiting. Diarrhea.
An important note for thyroid patients: Taking magnesium too close to your daily thyroid hormone replacement drugs can affect the absorption of your medication and thyroid hormone levels.
Caffeine speeds up your metabolism¹. This can cause temporary relief of hypothyroid symptoms, but can also potentially put more stress on your thyroid. If you have hyperthyroid, then caffeine can make your symptoms worse.
So if you do, it's a good idea to limit your intake of Brussels sprouts, cabbage, cauliflower, kale, turnips, and bok choy, because research suggests digesting these vegetables may block the thyroid's ability to utilize iodine, which is essential for normal thyroid function.
Fruits: Apples, Pears and Citrus
Apples, pears, plums and citrus fruits are abundant with pectins, which help with detoxifying the body of mercury – one of the most critical metals that have been connected to thyroid problems.
Iodine. Moderate amounts of iodine supplements can help prevent autoimmune diseases like Hashimoto's and Graves' — and may reduce symptoms of hypothyroidism. Your body cannot produce iodine on its own, so it depends on dietary iodine to produce and secrete thyroid hormones, T3 and T4.
Results: We found that vit-B12 deficiency and vit-D deficiency were associated with autoimmune hypothyroidism, and that there was a negative correlation between vit-B12 and vit-D levels and anti-TPO antibodies in these patients.
As the recommended daily allowance of 400 IU of vitamin D has been shown to be inadequate for most people, I generally recommend 5,000 IU per day as a starting point for my clients with Hashimoto's. Taking your vitamin D supplements with a meal can be helpful in increasing its absorption by 30-50 percent.