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Hypothyroidism (Underactive Thyroid)

A condition where the thyroid gland does not produce enough thyroid hormones, leading to slowed metabolism and various symptoms.

Medical Disclaimer

This information is for educational purposes only and is not a substitute for professional medical advice. Always consult with a qualified healthcare provider for diagnosis and treatment.

Overview

Hypothyroidism occurs when the thyroid gland fails to produce sufficient thyroid hormones. The thyroid is a butterfly-shaped gland in the neck that regulates metabolism, energy production, and many body functions.

The most common cause is Hashimoto's thyroiditis, an autoimmune condition where the immune system attacks the thyroid. Other causes include thyroid surgery, radiation therapy, certain medications, and iodine deficiency.

Hypothyroidism affects approximately 4-5% of the population, with women being 5-8 times more likely to be affected than men. It often develops gradually and may be undiagnosed for years as symptoms are often attributed to aging or other conditions.

Common Symptoms

  • •Fatigue and low energy
  • •Unexplained weight gain
  • •Feeling cold when others are comfortable
  • •Dry skin and hair
  • •Hair loss
  • •Constipation
  • •Depression and mood changes
  • •Memory problems and brain fog
  • •Muscle weakness and aches
  • •Slow heart rate
  • •Puffy face and swelling
  • •Irregular or heavy menstrual periods

Key Blood Markers

TSH (Thyroid Stimulating Hormone)

Often elevated (>4.5 mIU/L)

The primary screening marker - elevated in hypothyroidism as the pituitary tries to stimulate the underactive thyroid

Free T4 (Thyroxine)

Usually low

The main thyroid hormone produced - low levels confirm hypothyroidism

Free T3 (Triiodothyronine)

Often low or low-normal

The active thyroid hormone - may be low or normal in hypothyroidism

TPO Antibodies

Often elevated if Hashimoto's

Indicates autoimmune thyroid disease (Hashimoto's) - the most common cause of hypothyroidism

Frequently Asked Questions

Can hypothyroidism be cured?
Hypothyroidism is typically a lifelong condition requiring daily thyroid hormone replacement. However, some cases (postpartum, medication-induced) may be temporary. With proper treatment, most people lead normal, healthy lives.
How long does it take to feel better on thyroid medication?
Many people notice improvement within 1-2 weeks of starting medication. However, full symptom resolution may take 4-6 weeks as hormone levels stabilize. Dose adjustments are often needed in the first few months.
Can you have hypothyroid symptoms with normal TSH?
Yes, some people experience symptoms with TSH in the "normal" range (especially 2.5-4.5). This is called subclinical hypothyroidism or thyroid resistance. Full thyroid panel including Free T3/T4 can provide more information.
Does hypothyroidism cause weight gain?
Hypothyroidism can cause modest weight gain (typically 5-10 lbs) due to slowed metabolism and fluid retention. Significant weight gain is usually not solely due to thyroid issues. Treating hypothyroidism helps normalize metabolism.

Quick Facts

  • Key Markers:4
  • Common Symptoms:12

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