Hypothyroidism is a chronic condition that effects nearly 12 percent of Americans at some point during their lifetime. Despite its prevalence, it is estimated that upwards of 60 percent of those with hypothyroidism are not aware of their condition. Although there are several symptoms indicative of hypothyroidism, many of them are shared with other conditions which can lead to misdiagnosis. One way to better identify thyroid malfunction is by taking a look at your feet. Issues involving the feet are a highly indicative yet frequently overlooked component of hypothyroidism.
What is Hypothyroidism?
The thyroid gland is responsible for regulating essential bodily functions that influence numerous factors of wellness including energy level, skin health, water retention, fat storage, and much more. The small butterfly-shaped organ located in the neck, interacts with the body through the production of various hormones. Thyroid hormones control the speed of various cells, tissues, and systems throughout the body.
A decrease in thyroid function, known as hypothyroidism, can cause a universal slowing of virtually all activity and subsequent development of many symptoms. Some of the most common symptoms caused by hypothyroidism include fatigue, depression, weight gain or inability to lose weight, muscle and joint pain, sensitivity to cold, constipation, and “brain fog.” Unfortunately, these telltale signs of hypothyroidism are frequently misattributed to other conditions leaving the underlying thyroid dysfunction to go untreated. One of the most frequently overlooked or discounted indicator of hypothyroidism is dysfunction relating to the feet.
Foot-Related Symptoms of Hypothyroidism
At first thought it may seem that reduced thyroid function would have little impact on extremities including the feet. However, because of the powerful influence of the thyroid, hypothyroidism and other thyroid issues can actually trigger notable dysfunction of almost any region in the body including the feet. The following issues may be caused by a decline in thyroid function.
Tingling or Numbness
Paresthesia is the medical term for the numbness, tingling, or pins and needles sensation we feel when part of the body “falls asleep.” Most often this experience is temporary and is caused by sitting in the wrong position for too long. However, autoimmune conditions, such as Hashimoto’s thyroiditis (a leading cause of hypothyroidism), can initiate paresthesia. If you regularly experience sensory irregularities it is important to consider autoimmune thyroid disease as a possible contributor.
Changes in Skin Quality or Texture
Multiple studies show a connection between hypothyroidism and coarse, rough, and dry skin. Some research suggests that these attributes may be present in more than half of those suffering from hypothyroidism. One study found that upwards of 33% of hypothyroid patients may exhibit palmoplantar keratoderma, a grouping of skin conditions that induces a thickening of the skin in the palms of the hands and soles of the feet. If you notice textural changes of the feet or elsewhere, consider being tested for thyroid disease.
Swelling of the feet is typically indicative of chronic illness such as cardiovascular disease, diabetes, or kidney issues. However, swelling of the feet, known as edema, may also be caused by poor thyroid function. In advanced cases, hypothyroidism may cause pitting edema, wherein pressing on the impacted location will cause an indentation to remain for an extended period even after the pressure is removed. It is estimated that nearly 55 percent of hypothyroid patients will see pitting edema develop in their extremities.
Pain and Discomfort
Extended periods of compression due to swelling of the foot can cause irreparable damage to nerves and muscles in the area resulting in chronic pain. Furthermore, if swelling is sustained, inflammation is likely to develop, which can lead to arthropathy (a condition similar to arthritis that is exclusive to the feet). The continuous swelling prompted by hypothyroidism may also lead to the development of tarsal tunnel syndrome. This condition is caused by pinching of the nerves or muscle damage in the foot and is accompanied by pain and burning, or tingling sensations.
One of the many roles of thyroid hormone is facilitating the conversion of beta-carotene into vitamin A. Beta-carotene is the substance in carrots that provides their distinct orange color. If the thyroid is unable to effectively convert beta-carotene, any excess will be stored in the outer layers of skin. This can lead to discoloration or yellowing of the skin, most often in the soles of the feet or palms of the hands.
One of the most common complaints of hypothyroidism is feeling cold or having difficulty dealing with cooler temperatures. As thyroid function declines so too does circulation. Reduced circulation can lead to sensations of coldness. When temperature falls, the body attempts to conserve heat and keep the essential systems warm. Extremities like the feet are low priority, which makes them particularly susceptible to poor circulation and decrease in temperature.
Chronic pruritus, or itchiness of the skin, may develop in the presence of hypothyroidism. Although the itchiness associated with hypothyroidism may occur across the body, discomfort tends to be located primarily in the feet, legs, or scalp. This may be in part due to skin dryness. However, research indicates that chronic pruritus and even urticaria or hives, may be triggered by Hashimoto’s thyroiditis.
Changes in Nail Quality
Thyroid hormone is important for maintaining healthy skin and nails. A deficiency of thyroid hormone can prompt a change in the quality and texture of cuticles of both the hands and feet. Those with hypothyroidism may notice irregularities in their fingernails and toenails including, slow growth, yellowing, dryness, thickening, cracking, longitudinal ridges, and separation from the nail bed.
Taking Steps Towards Identifying Hypothyroidism
Thyroid disease can be difficult to identify because of the broad collection of symptoms it presents. Worse still, many of its signature symptoms are shared with other conditions, thereby making diagnosis even more challenging. However, it may be possible to better recognize hypothyroidism by taking a looking at your feet. Hypothyroidism may cause multiple foot-related disruptions including swelling, pain, and abnormal sensations. If you are experiencing any of the symptoms discussed in this article, you may be suffering from hypothyroidism. Talk to your doctor about thyroid testing and treatment.
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