10 Signs You May Have an Underactive Thyroid (Hypothyroidism)

If you’ve been feeling “off” but can’t quite put your finger on why, your thyroid may be worth a closer look.

The thyroid is a small butterfly-shaped gland located in the front of your neck. Despite its size, it plays a major role in regulating your metabolism, energy levels, body temperature, heart rate, digestion, mood, and more. When the thyroid isn’t functioning properly, the symptoms can be surprisingly broad and often mistaken for stress, aging, burnout, or simply having a busy life.

Here are 10 common signs that may suggest you have hypothyroidism:

1. Persistent Fatigue

Many patients describe it as a profound lack of energy that doesn’t improve with rest. They wake up feeling unrefreshed, struggle to maintain stamina throughout the day, and often feel as though their physical and mental energy reserves are never fully replenished.

2. Weight Gain and Other Metabolic Changes

Thyroid hormone plays a central role in regulating metabolic function. When levels are low, metabolism slows, which can contribute to gradual weight gain, fluid retention, elevated LDL cholesterol, and, in some individuals, worsening insulin resistance.

3. Increased Sensitivity to Cold

One hallmark symptom of hypothyroidism is increased sensitivity to cold. As metabolism slows, the body’s ability to generate heat becomes less efficient, leaving many patients feeling unusually cold - even in environments that others find comfortable.

4. Hair Thinning and Dry Skin

Many patients first notice subtle changes in their appearance. Hair may become thinner, more brittle, or shed more than usual, while the skin often becomes dry, rough, and less resilient. These changes occur because thyroid hormone is essential for normal skin and hair follicle function.

5. Brain Fog

Hypothyroidism can affect cognitive function, leading to difficulty concentrating, forgetfulness, slowed mental processing, and a feeling that tasks require more effort than they once did.

6. Constipation

Thyroid hormone helps regulate gastrointestinal motility. When levels are low, digestion slows, often resulting in persistent constipation that may not respond to the usual dietary interventions.

7. Depression or Low Mood

Thyroid hormone influences multiple neurotransmitter systems involved in mood regulation. Some individuals experience low mood, decreased motivation, emotional blunting, or symptoms that closely resemble depression.

8. Muscle Aches, Weakness, or Reduced Exercise Tolerance

Low thyroid hormone can affect both muscle metabolism and cardiovascular performance. Patients may notice muscle aches, stiffness, reduced strength, slower recovery after exercise, or a decline in physical endurance that feels disproportionate to their activity level. A slower-than-normal heart rate may also occur.

9. Menstrual Changes or Difficulty Getting Pregnant

Thyroid hormone plays an important role in reproductive health. Hypothyroidism may contribute to irregular or heavy menstrual periods, ovulatory dysfunction, difficulty conceiving, and an increased risk of miscarriage.

10. Puffy Face, Voice Changes, or Neck Swelling

In more significant cases, hypothyroidism can lead to fluid accumulation in the tissues, resulting in facial puffiness, swelling around the eyes, hoarseness, a deeper voice, or enlargement of the thyroid gland (goiter).

If you’re experiencing symptoms that may be related to hypothyroidism, would like your thyroid evaluated, or need ongoing management of an existing thyroid condition, schedule an appointment at Evora Women’s Health. We offer comprehensive thyroid evaluations and evidence-based treatment tailored to your individual needs.