Should you take Vitamin D if you have Hyperparathyroidism

Should you take Vitamin-D if you have Hyperparathyroidism?

“Should you take Vitamin D if you have Hyperparathyroidism?”  This question has been a topic of debate since decades, and the precise answer is: It depends on the type of hyperthyroidism you have. If you've primary hyperparathyroidism, then you should NOT take vitamin D. But if you have secondary hyperparathyroidism (due to low vitamin D), then you should take it to improve your symptoms.

The human body is complex, with all the different glands and physiological mechanisms interconnected with each other. Even after all the advancement in medical science, doctors still get confused about the root-cause of some diseases, and end up prescribing treatment options that exacerbate the disease rather than improving it.

One of such diseases is hyperparathyroidism.

To understand how Vitamin D is linked to different types of hyperparathyroidism and why you should or shouldn't take vitamin D as a treatment, let's discuss hyperparathyroidism and its types :

Hyperparathyroidism and its types

There are 4 pea-sized parathyroid glands present in your neck, located near the thyroid gland. They secrete parathyroid hormones which control the levels of vitamin D, phosphorus and calcium in the blood.

Hyperparathyroidism, in general, is the disease of the parathyroid gland, characterized by the enlargement of at least one or all the parathyroid glands. This causes the glands to secrete parathyroid hormones excessively and leads to different issues in the body and may even become a cause of other diseases such as hyperplasia, osteoporosis, rickets etc.

Based on the number of thyroid glands affected and the reason of their enlargement, the disease is classified into three types:

1. Primary hyperparathyroidism
2. Secondary hyperparathyroidism
3. Tertiary hyperparathyroidism

LINK BETWEEN VITAMIN D AND DIFFERENT TYPES OF HYPERPARATHYROIDISM

The question “Should you take Vitamin D if you have Hyperparathyroidism?”, which is the main topic of this article, can be answered by knowing the link between Vitamin D and different types of hyperparathyroidism.

The reasons for developing hyperparathyroidism are different for each type of the disease, and knowing how Vitamin D is linked to each type can help you decide whether it's safe for you to take it as part of your treatment.

Primary hyperparathyroidism (pHPT) and Vitamin D

Vitamin D should NOT be taken if you have PRIMARY Hyperparathyroidism, because it will worsen the disease. Why? Keep reading.

Primary hyperparathyroidism is characterized by the enlargement of at least one parathyroid gland, resulting in excessive production of Parathyroid hormone. The most common reason for this enlargement is the presence of benign tumors on the gland. In very rare cases these tumors are cancerous.

The tumor causes overproduction of the parathyroid hormone in case of Primary Hyperparathyroidism. Since parathyroid hormone controls the absorption of calcium in the blood, more calcium is absorbed by the blood than normal, which results in high levels of calcium in the blood.

Vitamin D isn't the cause, it's the result!

Now this is where the link between Vitamin D and primary hyperparathyroidism can be understood.

Know that “Vitamin D is what makes your body absorb calcium in your intestines, so a LOW Vitamin D level cannot ever be the reason for HIGH Calcium in the blood! In fact, the high level of calcium due to primary hyperparathyroidism is what causes low vitamin D levels in primary hyperparathyroidism patients”

Simply put, More Vitamin D = More Calcium.

Therefore, more calcium cannot be a result of less vitamin D. So, there's no point in taking Vitamin D as a treatment of primary hyperparathyroidism.

One important thing to understand here is Vitamin D deficiency isn't causing high levels of Calcium, the tumor is causing it. It's the abnormal growth of the parathyroid gland’s cells which is responsible for the overproduction of Parathyroid hormone and ultimately the elevation of Calcium levels in the blood.

You must be wondering: If Calcium levels are high in Hyperparathyroidism patients, how are their Vitamin D levels low?

The protective mechanism :

Primary hyperparathyroidism patients have high blood calcium and low vitamin D levels, which is a confusing state. So, how and why does this happen?

The excess secretion of Parathyroid hormone due to the parathyroid tumor causes the body to take out calcium from the bones and release it into the blood. This disturbs the body and triggers it to take protective measures to prevent further accumulation of calcium in the blood :

• Firstly, the body gets rid of this excess calcium (which has come from your bones and not from your diet) by eliminating it through your urine. This is why one-third of the people suffering from primary hyperparathyroidism have high calcium concentration in the urine.
• Secondly, and more importantly, it prevents the body from gathering more calcium by lessening the amount of Vitamin D available in your body. Since vitamin D is essential for calcium absorption in the intestines, if vitamin D levels are lowered, it will prevent the body from getting further amounts of calcium through the diet.

Simply put, in case of primary hyperparathyroidism, the deficiency of Vitamin D is a protective mechanism of the body to keep the disease from worsening. It's the result of the disease, not the cause. Therefore, taking Vitamin D if you have primary hyperparathyroidism is out of question. However, some doctors still confuse the whole point and give Vitamin D to the patients which only worsens the disease.

Adverse effects of taking vitamin D for primary hyperparathyroidism :

Since a high level of Calcium is the main characteristic of primary hyperparathyroidism, taking vitamin D will only further increase the calcium levels rather than normalizing it.

The possible adverse effects of taking vitamin D for primary hyperparathyroidism includes:

• More calcium in the urine which can lead to kidney stones
• The additional vitamin will cause additional accumulation of calcium in the blood. This is dangerous because it can lead to strokes. This happens rarely but one should always be cautious!

Since tumor is the cause of high calcium in primary hyperparathyroidism patients, taking vitamin D is a totally wrong choice and should never be considered. It's counterproductive. However, the main cause of the issue, which is the tumor, should be eliminated through surgery.

Secondary hyperparathyroidism and Vitamin D

In contrast to primary hyperparathyroidism, secondary hyperparathyroidism is the condition in which the parathyroid itself isn't the problem, but it becomes affected due to underlying issues. These underlying issues affect all the parathyroid glands, causing them to become hyperactive.

Understanding these underlying issues is crucial to understand how Vitamin D is linked to secondary hyperparathyroidism and how it can help treat the disease.

What are the underlying causes? Is Vitamin D one of them?

Yes. Vitamin D deficiency is one of the most common causes of secondary hyperparathyroidism besides kidney failure. Vitamin D is the cause here, and not the result, contrary to what happens in primary hyperparathyroidism.

What happens is, due to Vitamin D deficiency, the body is unable to get adequate amounts of calcium needed by it. Since parathyroid hormones regulate the levels of calcium in the blood, the low calcium levels stimulate the parathyroid glands to make more hormones. When the glands keep getting stimulated constantly for a long time, they become enlarged and hyperactive resulting in secondary hyperparathyroidism.

Apart from Vitamin D deficiency, secondary hyperparathyroidism can also be caused by kidney failure. When the kidney fails to produce enough vitamin D or eliminate the phosphorus present in the body, the ultimate result is a low level of calcium in the blood. This again triggers the parathyroid gland and stimulates it to produce more hormones.

Either secondary hyperparathyroidism is caused by Vitamin D deficiency or kidney failure, the trigger is the low calcium level and the resulting overactive parathyroid glands cause increased bone resorption to make up for the less calcium in the body. This results in a decreased overall bone density and may cause harmful conditions such as calciphylaxis, necrosis and ulcers.

Can vitamin D help treat secondary hyperparathyroidism?

The best way to treat secondary hyperparathyroidism is to identify the root-cause and fix it. If the disease is caused by a simple vitamin D deficiency, it can be treated by raising the vitamin D levels to the normal range. This is done by taking Vitamin D supplements along with Calcium supplements. By taking supplements, the vitamin D levels will be restored to the normal range which will help the intestines absorb adequate calcium from the diet. Once this is achieved, the parathyroid hormones will no longer be stimulated and will slowly become normal.

If kidney failure is the cause of the disease, the only treatment option is a kidney transplant if all the medical therapies (including phosphate binders, vitamin D supplements and calcimimetics) don't work.

The bottom line 

There have been conflicting opinions of doctors regarding the use of Vitamin D as a treatment of hyperparathyroidism, but these conflicts are cleared by understanding the cause of each type of hyperparathyroidism. Vitamin D should not be taken if you have primary hyperparathyroidism as it may worsen the disease. However, if you have secondary hyperparathyroidism, you can take Vitamin D as a treatment.

References 

• https://www.parathyroid.com/low-vitamin-d.htm

• https://columbiasurgery.org/conditions-and-treatments/secondary-hyperparathyroidism
• https://www.aafp.org/afp/2005/0101/p46.html
• https://pubmed.ncbi.nlm.nih.gov/22059217/
• https://www.endocrine-abstracts.org/ea/0032/ea0032p134
• https://www.parathyroid.com/low-vitamin-d.htm