Medically Reviewed by Hugh L. Willcox, III, MD, FACS

The thyroid gland plays a vital role in regulating metabolism, energy levels, and overall body function. Yet, many people don’t realize just how much a small change in its function can affect their daily health and well-being.

Located at the base of the neck, the thyroid produces two main hormones: thyroxine (T4) and triiodothyronine (T3). These hormones help control how the body uses energy, influencing heart rate, body temperature, and how efficiently calories are burned. Even a slight imbalance can cause noticeable symptoms.

Thyroid disease can appear in very different ways. An overactive thyroid (hyperthyroidism) may cause anxiety, restlessness, rapid heartbeat, heat intolerance, and unexplained weight loss. While an underactive thyroid (hypothyroidism) tends to slow things down which leads to fatigue, weight gain, cold sensitivity, dry skin, constipation, and mood changes. Sometimes, thyroid issues can be subtle and may even show up as difficulty concentrating, depression, or a general lack of productivity.

One of the most common reasons people begin to suspect a thyroid problem is due to unexplained weight changes. When your thyroid isn’t producing enough hormone, your metabolism slows, making it easier to gain weight. If it produces too much, your metabolism speeds up, leading to weight loss, even without changes in diet or exercise. This direct link between thyroid hormone levels and energy use is one of the key ways doctors identify thyroid imbalances.

Treatment for thyroid disease depends on whether the gland is overactive or underactive. In most cases, it begins with medication. Patients with an underactive thyroid are typically prescribed hormone replacement therapy to restore normal T4 and T3 levels. Those with an overactive thyroid may be treated with antithyroid medications that reduce hormone production. In some cases, surgery to remove part or all of the thyroid gland may be the best option.

As for prevention, there are not many lifestyle changes that can fully prevent thyroid disease. Many cases are linked to autoimmune conditions, family history, or other underlying factors. However, keeping up with your annual checkups can make a big difference. Routine blood work during these visits allows your primary care provider to monitor thyroid hormone levels.

If you are experiencing changes in energy, mood, or weight, it may be worth asking your doctor to check your thyroid levels. Paying attention to these small signs can make a big impact on your overall health.