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The term restless legs syndrome is as bad as it sounds. It is a condition where you have an uncontrollable urge or need to move your legs. And this urge can show up at the worst of times, like when you are trying to sleep or once you have just settled in for a long work meeting. Several factors play into this annoying syndrome, but one of them may be an underactive thyroid. Here, we dive into how restless leg syndrome and hypothyroidism may be connected and what you can do about it.
Restless leg syndrome (RLS) is a bothersome condition where people constantly need to move their legs (sometimes, this can even extend to their upper extremities). And while it may sound bizarre, it is a widespread problem. According to the Restless Legs Syndrome Foundation, RLS is perhaps the most common condition you have never heard of, affecting more people that even type 2 diabetes.
RLS is a neurological condition that can start at any age but generally worsens as people age. We don't always know what causes RLS, but a few potential theories can explain why this condition may occur.
Firstly, there may be some genetic component. Some research shows that specific genes can code for RLS, and it can run in families. For genetic sources of RLS, the symptoms usually show up before age 40.
Secondly, there seems to be a connection between dopamine, a neurotransmitter used by a part of the brain called the basal ganglia to help control muscle movement. When nerves in this part of the brain are damaged, dopamine levels may be reduced, thus causing muscle spasms. Involuntary movements can also occur when dopamine levels are low.
Thirdly, underlying health conditions may be behind RLS. The following medical conditions may cause RLS to develop:
- Chronic kidney disease
- Iron deficiency anemia
- Rheumatoid arthritis
- Parkinson's disease
Chronic health conditions may be the most common source of RLS, but it is important to note that this problem can also appear in the third trimester of pregnancy.
Lastly, RLS may be a side effect of certain medications that alter neurotransmitter levels in the brain. For example, antidepressants, lithium, and some antipsychotics may cause RLS.
Despite being a frustrating condition, RLS can impact your quality of life in some pretty significant ways. Firstly, most people experience RLS at night, which can interfere with the quality of sleep. Shorter sleep durations can create a cascade of problems, such as a decrease in the ability to think clearly and process information, an increase in stress, and feelings of being run down.
There is a connection between RLS and hypothyroidism. It appears that thyroid disease, in general, maybe a predisposing factor for this condition, which can worsen insomnia and also accompany hypothyroidism.
How hypothyroidism causes RLS is still unclear, but some studies suggest that an imbalance in thyroid hormone levels can affect the dopaminergic system. RLS appears to be more severe in patients with hyperthyroidism (an overactive thyroid) than in individuals with hypothyroidism as a result of treatment. Indeed, higher thyroid hormone levels, such as in pregnant women and people with Graves' disease, cause an increase in a muscular activity like tremors and a hyperkinetic state.
While we still do not fully understand how thyroid hormone and dopamine influence one another, there does appear to be a relationship between the two that may be affected in people with thyroid disease.
The research shows that correcting thyroid hormone imbalance can improve RLS symptoms. In one study looking at the prevalence of RLS in patients with and without thyroid disease, 33% of patients with hypothyroidism experienced complete recovery from RLS once they were on the right thyroid hormone medication.
Aside from assessing thyroid function, it is important to look at other health conditions behind this problem. Recall that many chronic conditions like diabetes, kidney disease, and other autoimmune conditions may also trigger RLS symptoms. If you have a known chronic health condition, following a sound treatment plan is suggested to keep your body as healthy as possible.
According to the Restless Legs Syndrome Foundation, several other steps can be taken to help diminish your symptoms.
First, following a healthy diet is a key pillar in helping alleviate or prevent symptoms of RLS from triggering or worsening. For people with RLS, it pays to watch your iron intake so that you know you are getting enough, as iron deficiency anemia is a common symptom of RLS. Certain foods and compounds within foods may trigger RLS, which can differ between people. However, caffeine is frequently associated with increasing muscular tremors, as are refined sugars and alcohol.
There are also several FDA-approved drugs to treat RLS. Gabapentin, Ropinirole, Pramipexole, and Rotigotine have all been approved. Some doctors may also prescribe "off-label use" medications to treat RLS.
Since hypothyroidism and RLS can both be triggers for each other, monitoring and maintaining normal thyroid function is crucial. With an at-home thyroid test kit, you can work with your provider to understand where your thyroid hormone levels are at and how to help prevent symptoms of RLS from increasing. In addition, adhering to a meal plan and dietary changes that can help support your thyroid and RLS symptoms can be done with a Paloma Health nutritionist.