Cannabis And Hypothyroidism: A Scientific Look Into Treatment

The thyroid gland is an integral part in the endocrine system of our bodies that regulate breathing, heart rate, body weight, menstrual cycle, body temperature, and cholesterol levels to name a few.

It is about two inches in length and is located in front of the throat below the prominence of thyroid cartilage, also known as the Adam’s apple. The thyroid has two sides called lobes that lie on either side of the windpipe, and is usually connected by a strip of thyroid tissue known as an isthmus.

The thyroid gland uses iodine from the food to make two main hormones called triiodothyronine (T3) and thyroxine (T4). It is important that T3 and T4 levels are neither too high nor too low. Two glands in the brain, the hypothalamus and the pituitary, communicate to maintain T3 and T4 balance in the body via the thyroid stimulating hormone (TSH).

In Hashimoto’s thyroiditis, antibodies directed against the thyroid gland lead to chronic inflammation known as chronic lymphocytic thyroiditis, rendering it an autoimmune condition.

Hashimoto’s disease is the most common cause of hypothyroidism or under-active thyroid, in the United States. It primarily affects middle-aged women but also can occur in other demographics as well. It was first described by the Japanese physician Hakaru Hashimoto in 1912.

Characteristics of Hashimoto’s thyroiditis

(image via Universal Medical)

Due to the fact that the condition usually progresses very slowly over many years, people with Hashimoto’s thyroiditis may not have any symptoms early on, even when the characteristic TPO or thyroid peroxidase antibodies may be detected in blood tests. TPO can be a good indicator of whether a patient will develop thyroid conditions in the future due to familial affiliations.

Symptoms will exhibit as those of any hypothyroid conditions. These include weight gain, fatigue, joint and muscle pain, constipation, heat intolerance, fertility issues, hair loss or thinning of hair, irregular or heavy menstrual periods, and slowed heart rate. There may be more symptoms as well.

The diagnosis of Hashimoto’s thyroiditis is made when patients exhibit symptoms of hypothyroidism, accompanied by the finding of a goiter or an enlarged thyroid gland on physical examination, and laboratory tests consistent with hypothyroidism with an elevated serum TSH and low thyroid hormone (free thyroxine) levels. Antibodies against TPO, when measured, are usually elevated.

Occasionally, the disease may be diagnosed early on, especially in people with a strong family history of thyroid disease, during routine laboratory screening, even before the patient develops symptoms of hypothyroidism. In these cases, usually mild elevation of blood TSH is seen, with normal levels of thyroid hormones and positive TPO antibodies.

Treatment is managed by giving synthetic levothyroxine, also known as synthroid, orally at an appropriate dose. It is inexpensive, very effective in restoring normal thyroid hormone levels, and results in improvement of symptoms of hypothyroidism. Most patients with Hashimoto’s thyroiditis will require lifelong treatment with levothyroxine.

How does cannabis help?

Cannabis has very immune suppressing properties that help with many autoimmune disorders like Hashimoto’s and lupus.

Studies have shown that tetrahydrocannabinol (THC) increases TH-2 , a type of immune cells known as T-cells, and suppresses TH-1, another type of T-cell, by inhibiting interferons (IFN), which are signalling proteins that let the body know when a foreign body is present, and interleukin-12 (IL-12), which are protein cells secreted by white blood cells.

THC affects IL-12 receptors. IL-12 can turn on genes that cause death of certain tissues, like the thyroid gland. By inhibiting this mechanism, it can be a good thing for patients with Hashimoto’s.

In addition to that, THC promotes IL-4, which is not ideal. IL-4 can activate immunoglobulin E (IgE) which is involved with allergic reactions and some hypersensitivities, that can potentially be fatal.

However, the fact that both cannabinoid receptors CB1 and CB2 have been found on immune cells suggests that cannabinoids and the endocannabinoid system play an important role in the regulation of the immune system.

Recent studies have shown that administration of THC in mice triggered apoptosis, or programmed cell death, in T cells and dendritic brain cells, resulting in immunosuppression.

Hashimoto’s was originally thought to be a TH-1 dominant autoimmune disorder, but this has since been shown to be an oversimplification since some people have overactive TH-2 systems.

While THC can definitely be anti-inflammatory, it may not be as effective if a patient is TH-2 dominant or already has an overactive TH-2 response.

That being said, there is ample evidence that it can help calm TH-1. However, more studies do need to be done since the ones that were already done have been promising.

It is also to be noted that the effects of cannabis on the endocrine system has not yet been properly studied. There may be a possibility that for those suffering with obesity it may exacerbate their symptoms after cannabis use. Patients are highly encouraged to speak with the primary care physicians before treatment to discuss all risks and benefits.