Thyroid function influences our overall health and wellbeing.
When the function of the butterfly-shaped gland is abnormal, we experience an array of symptoms that affect our quality of life. For that reason, and many others, it’s important to be proactive in order to support thyroid health.
Of course, diet plays a huge role in the function of this gland. Generally speaking, our body requires a whole spectrum of vitamins and minerals to keep us healthy.
Potassium is one of those minerals, and you're probably well aware it’s crucial for healthy blood pressure. But, in this post, we’re going to focus on its relationship with the thyroid.
Does thyroid really need potassium to function properly?
What happens if levels of this mineral are too low? We explore these questions in this article to understand the connection between thyroid health and potassium.
The beneficial effects of potassium in our bodies
Potassium, sodium, magnesium, phosphorous, calcium, and many others are recognized as valuable minerals for the human body.
They are also electrolytes - electrically-charged minerals whose balance is inevitably important for maintaining multiple body functions running as they are expected to.
Potassium is known to be the third most common mineral. It is found in the human body where it has many valuable functions.
Most of the potassium is found in the muscle cells, while the rest is to be found in the bones, liver, and red blood cells.[i]
Potassium helps to regulate the fluid balance in the body, and with that, it shields us from dehydration, heart problems, and kidney problems. [ii]
The mineral also plays an important role in activating nerve impulses throughout the nerve system, which are needed for actions such as muscle contractions, and for a body’s heartbeat to be regulated properly. A diet high in potassium has been found to be able to reduce the high blood pressure, prevent osteoporosis[iii], protect from strokes, prevent kidney stones[iv] , etc.
The importance of potassium for thyroid health
Thyroid health is not left behind when it comes to the many beneficial effects of potassium.
In fact, potassium and iodine are the two most important minerals when it comes to preserving our thyroid gland in good health. How?
More studies are necessary to elucidate all the mechanisms of action through which potassium contributes to thyroid health.
But, the primary role of the mineral could also be the reason behind its favorable impact on the butterfly-shaped gland.
As mentioned above, potassium takes part in electrolyte balance which helps to regulate blood pressure. Therefore, inadequate levels of the mineral could negatively affect your blood pressure and other aspects of health.
For example, symptoms of hypokalemia (low potassium) include[v]:
- Weakness and fatigue
- Muscle cramps and spasms
- Digestive problems
- Heart palpitations
- Muscle aches and stiffness
- Tingling and numbness
- Breathing difficulties
- Mood changes
- High blood pressure[vi]
Do you notice anything interesting in the above-mentioned symptoms?
Some of them are also symptoms of hypo- and hyperthyroidism.
For instance, hypothyroidism is also indicated by fatigue and muscle stiffness and weakness, irritability, and digestive problems such as constipation[vii].
On the flip side, hyperthyroidism is also characterized by symptoms such as increased bowel movements, fatigue, weakness, and rapid heart rate[viii].
Everything in our body is connected so it is natural that low potassium may have the same symptoms or contribute to symptoms of hypothyroidism and hyperthyroidism.
After all, in hyperthyroid patients, potassium deficiency may aggravate their cardiac symptoms and make their heart pump even faster.
The same way a hypothyroid person with potassium deficiency may also experience more severe symptoms that are listed above. This means that in addition to the treatment of hypo- and hyperthyroidism, lifestyle modifications are also necessary to ensure an affected person has normal levels of potassium in the body. Additionally, we need to pay attention to how much potassium we consume and ensure our diet contains sources of this mineral (see below).
Hypothyroidism and potassium
Hypothyroidism or underactive thyroid gland involves reduced production of thyroid hormones.
The relationship between hypothyroidism and potassium is poorly elucidated, and more research is needed to uncover how they affect one another.
What many people don't realize is that hypothyroidism can potentially lead to high potassium levels (hyperkalemia). How?
Hypothyroidism can slow down urinary potassium excretion even if a person’s kidneys are healthy. Slowed excretion leads to accumulation of potassium and causes hyperkalemia. Horie et al. found that hyperkalemia develops in a small percentage of hypothyroid patients after thyroid hormone withdrawal, particularly in patients older than 60 who are using antihypertensive drugs[ix].
Symptoms of hyperkalemia may include fatigue and weakness, irregular heartbeat, numbness, nausea, vomiting, blood pressure elevation, and others.
Hyperthyroidism and potassium
Contrary to hypothyroidism, hyperthyroidism is characterized by the overactive thyroid gland and excessive production of thyroid hormones.
Although it has been confirmed that hyperthyroidism is also associated with changes in potassium levels, evidence on the subject is still limited and calls for further research of the topic.
One of the older studies regarding total body potassium in relation to thyroid hormones in hyperthyroid patients found that in those with low levels of the mineral, potassium concentration rose when T3 and T4 were restored to normal.
The study also found that considerable loss of potassium can be considered usual for hyperthyroidism. Among hyperthyroid patients, the greatest muscular weakness was observed in those with the highest loss of potassium.
Gaining weight can also lead to higher potassium levels in hyperthyroid patients. This is particularly important if we bear in mind that hyperthyroidism can lead to weight loss which, as you can see, also has a negative impact on mineral balance.
Scientists concluded the study confirming that potassium levels are associated with hyperthyroidism and pointing out that potassium changes are closely related to T3 concentrations, but unrelated to T4 levels[x].
When talking about hyperthyroidism and potassium, it is also important to mention whole body paralysis. Some hyperthyroid patients can have whole body paralysis which is generally associated with very low levels of potassium in the blood.
This condition is called thyrotoxic periodic paralysis (TPP). Evidence shows that TPP is associated with Graves' disease, an autoimmune condition and one of the most common causes of hyperthyroidism.
Despite this fact, the exact causes of TPP and low potassium in hyperthyroid persons are not clear, high sugar diets and too much exercise could trigger the problem.
TPP which can lead to low potassium usually occurs in the shoulders and hips, but it can affect the whole body or any other area and tends to last between three hours and a whole day. In other words, hyperthyroidism may contribute to whole-body paralysis and low potassium levels[xi].
This calls for adequate management of this condition and shows that taking care of the whole body is the best way to avoid any potential unfortunate scenarios in the future. By balancing potassium (and other minerals), we also support thyroid function and vice versa.
How much potassium do we need every day?
A common misconception about potassium and other minerals is that the more we take, the better. However, our body requires a specific amount of each nutrient during the day for optimal function. Sticking to the recommended intake allows you to balance potassium levels and keep them in a healthy range in order to prevent both hypokalemia and hyperkalemia.
So, how much potassium you need to consume during the day?
According to the National Institutes of Health, adult men need to consume about 3400mg of potassium during the day. On the flip side, women need 2600mg of this mineral a day while the intake during pregnancy should rise to 2900mg, and when breastfeeding to 2800mg[xii].
Consuming adequate amounts of potassium, and other minerals have never been more crucial than it is today due to growing rates of nutritional deficiencies. Western diet characterized by high intake of trans fats, sugars, and other unhealthy ingredients could be to blame for nutritional deficiencies, and unfortunately that dietary pattern is popular today.
Generally speaking, hypokalemia or low potassium level occurs when the concentration of potassium in the blood is less than 3.5mmol per liter. Hyperkalemia or high potassium levels occur when the concentration of the mineral is higher than 5.5.mmol per liter. A blood test is necessary to diagnose both low and high potassium.
What most of us fail to realize is that diet is not the only factor that affects potassium levels, but our overall health and kidney function. A healthy lifestyle is crucial for optimal levels of potassium, but also for the thyroid gland.
Best sources of potassium
Potassium, like other nutrients, is widely present in our diet. With a well-balanced diet, it’s entirely possible to have healthy levels of potassium in the body and thereby prevent both deficiency and excessively high concentration of the mineral.
Some of the best sources of potassium are:
- Apricots and grapefruit
- Some dried fruits
- Cooked spinach
- Potatoes and sweet potatoes
- Cucumbers and zucchini
- Leafy greens
- Juices from orange, apricot, tomato, prune, and grapefruit (freshly-squeezed, not store-bought)
Besides the above-mentioned, other rich sources of potassium include lentils, kidney beans, soybeans, milk, chicken breast, yogurt, salmon, asparagus, apples, among others.
However, in order to get the most out of food sources of potassium, you need to modify your diet in general. If you tend to eat fast food and too many sweets, drink soda, and indulge in other unhealthy meals, you may want to consider reducing or eliminating their intake entirely.
The best way to get all the nutrients that fruits, vegetables, nuts, seeds, and other foods have to offer is to ensure our diet doesn’t revolve around meals with little to no nutritional value. Otherwise, our body wouldn’t be able to absorb all the valuable nutrients that it needs to function properly.
It’s not uncommon for people to take the importance of a well-balanced diet for granted mainly because they rely on the use of supplements. You may find this surprising, but dietary supplements are not the ideal source of potassium. The FDA limits the over-the-counter supplements to less than 100mg per serving[xiii], which is equal to 2% of the recommended daily value.
It’s due to the risk of overdose.
Therefore, try to modify your diet as much as possible and consult your doctor about the subject.
Potassium is a mineral we need for healthy blood pressure and overall health and wellbeing. Evidence confirms that levels of this mineral and thyroid function are connected.
Both hypothyroidism and hyperthyroidism can affect potassium levels and cause either hypokalemia or hyperkalemia. Adequate management of the underlying thyroid-related condition is vital for balancing potassium levels.
Doctors may want to consider testing their patients for high or low potassium if they exhibit symptoms of deficiency or sufficiency in the presence of thyroid problems.
Healthy lifestyle management of the underlying condition, and adequate intake of potassium-rich foods are crucial for the balance of this mineral, and it may also help improve thyroid health in the long run.
[i] Cheng, C., Kuo, E., & Huang, C. (2013). Extracellular Potassium Homeostasis: Insights from Hypokalemic Periodic Paralysis. Seminars in Nephrology,33(3), 237-247. doi:10.1016/j.semnephrol.2013.04.004
Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4131448/
[ii] Scales, K., & Pilsworth, J. (2008). The importance of fluid balance in clinical practice. Nursing Standard,22(47), 50-57. doi:10.7748/ns2008.07.22.47.50.c6634
Retrieved from http://journals.rcni.com/nursing-standard/the-importance-of-fluid-balance-in-clinical-practice-ns2008.07.22.47.50.c6634
[iii] Lambert, H., Boyd, V., Darling, A., Torgerson, D., Burckhardt, P., Frassetto, L., & Lanham-New, S. (2011). Dietary potassium and bone health: A systematic review and meta-analysis. Bone,48. doi:10.1016/j.bone.2011.03.450
Retrieved from https://link.springer.com/article/10.1007%2Fs00198-014-3006-9
[iv] Meschi, T., Maggiore, U., Fiaccadori, E., Schianchi, T., Bosi, S., Adorni, G., Borghi, L. (2004). The effect of fruits and vegetables on urinary stone risk factors. Kidney International,66(6), 2402-2410. doi:10.1111/j.1523-1755.2004.66029.x
Retrieved from https://www.sciencedirect.com/science/article/pii/S0085253815503475
[v] eight signs and symptoms of potassium deficiency (hypokalemia), Healthline.com Retrieved from https://www.healthline.com/nutrition/potassium-deficiency-symptoms
[vi] Why potassium helps to lower blood pressure? BloodPressureUK.org Retrieved from http://www.bloodpressureuk.org/microsites/salt/Home/Whypotassiumhelps
[vii] Hypothyroidism: overview, causes, and symptoms. EndocrineWeb.com Retrieved from https://www.endocrineweb.com/conditions/thyroid/hypothyroidism-too-little-thyroid-hormone
[viii] Hyperthyroidism symptoms, causes, treatments, and diet. MedicineNet.com Retrieved from https://www.medicinenet.com/hyperthyroidism/article.htm#hyperthyroidism_definition_and_facts
[ix] Horie I, Ando T, Imaizumi M. Et al. (2015) Hyperkalemia develops in some thyroidectomized patients undergoing thyroid hormone withdrawal in preparation for radioactive iodine ablation for thyroid carcinoma. Endocrine Practice 21(5):488-94. Doi: 10.4158/EP14532.OR Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/25667379
[xi] Chang, C. C., Cheng, C. J., Sung, C. C., Chiueh, T. S., Lee, C. H., Chau, T., & Lin, S. H. (2013). A 10-year analysis of thyrotoxic periodic paralysis in 135 patients: focus on symptomatology and precipitants. European journal of endocrinology, 169(5), 529–536. doi:10.1530/EJE-13-0381 Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3789562/
[xii] Potassium, National Institutes of Health. Retrieved from: https://ods.od.nih.gov/factsheets/Potassium-HealthProfessional/
[xiii] CFR – Code of Federal Regulations Title 21, U.S. Food and Drug Administration. Retrieved from: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=216.24