World Thyroid Day, oberserved every May 25, aims to highlight the significance of thyroid health, emphasizing timely detection and management of disorders like hypothyroidism and hyperthyroidism. It’s a global call to action for better education, testing, and treatment access, empowering individuals to prioritize hormonal balance for lifelong health and well-being.The thyroid gland is small, but its impact on our well-being is anything but insignificant. From controlling metabolism and temperature to regulating energy and heart rate, the hormones it secretes touch virtually every cell in the body. And when hormone levels swing out of balance, the repercussions can be wide-ranging resulting in symptoms that are frequently misinterpreted or mislaid and blamed on other causes. One of the most obvious and frequently reported indicators? Unexpected changes in weight.As thyroid disorder rates continue to escalate worldwide, identifying the early symptoms of thyroid dysfunction—particularly hypothyroidism is critical to diagnosing and treating it in a timely manner.What Is Thyroid Gland's Function in Your Body?At the bottom of your neck lies the butterfly-shaped gland called the thyroid, which is responsible for secreting two most important hormones: thyroxine (T4) and triiodothyronine (T3). These hormones control your body's metabolism—the manner in which your body produces energy from food. They also influence a variety of different functions in your body, such as:Heart rateBody temperatureDigestionMuscle strengthMenstrual cyclesBrain functionThe thyroid functions on the orders of the hypothalamus and pituitary gland, which coordinate their efforts to ensure hormone equilibrium. However, when this mechanism is disturbed, it leads to hypothyroidism (underactive thyroid) or hyperthyroidism (overactive thyroid). Link Between Thyroid Hormones and MetabolismWeight gain tends to be one of the earliest warning signs of an underactive thyroid, or hypothyroidism. A slow thyroid causes a slowing of the basal metabolic rate (BMR)—the rate at which your body requires calories to function when you are at rest. With a decreased BMR, you could gain weight even if you haven't altered your diet and activity level.Surprisingly, the weight gain is not just because of fat buildup. Fluid retention also happens due to hormonal imbalances, so the fluctuations on the scale are even more baffling for patients. Most describe frustration when their healthy eating and exercise regimens fail to deliver hoped-for gains only to later find that a thyroid condition was responsible.There are approximately 4.6% of the U.S. population living with hypothyroidism, and millions are undiagnosed, according to the American Thyroid Association. That increases the importance of awareness regarding subtle symptoms.Symptoms of the Thyroid That Must Not Be OverlookedAlthough weight fluctuations usually bring people into the doctor's office, thyroid abnormalities are typically paired with a group of symptoms:Fatigue: This is not the normal tiredness. Fatigue caused by hypothyroidism is profound and can be relentless, even after an entire night of sleep.Cognitive Changes: Most commonly, patients report a feeling of "brain fog," forgetfulness, or difficulty concentrating. These may be the only symptoms and are often ignored.Gastrointestinal Problems: Hypothyroidism can be slow to digest, producing constipation, bloating, or in some instances, Small Intestinal Bacterial Overgrowth (SIBO), which causes discomfort and impaired nutrient uptake.Sensitivity to Cold: Without an increased internal thermostat, hypothyroid patients will feel cold even when the surrounding environment is warm.Skin and Hair Changes: Dry, flaky skin and brittle hair or thinning of the hair are usually experienced. These are due to thyroid hormones' role in regulating skin cell turnover and health of the hair follicles.Overlooked Symptoms of ThyroidThyroid disease may affect the eyes as well. In Hashimoto's thyroiditis, which is a prevalent cause of hypothyroidism, patients develop dry eye or blurry vision. In Graves' disease, causing hyperthyroidism, patients may have bulging eyes, double vision, and eye irritation—a condition called Graves' Ophthalmopathy. Some Graves' patients develop these ocular changes in as many as one-third of cases.Data from the Fifth National Family Health Survey of India supports this, reporting thyroid-related disorders and goitre in 2.7% of women and 0.5% of men in the 15–49 age group. The visible swelling in the neck area and other signs demand awareness and timely thyroid function tests.Diagnosing Thyroid ConditionsObtaining a proper diagnosis requires 2 easy steps- physical examination to determine if there is swelling or nodules in the neck and blood work that determines:TSH (thyroid-stimulating hormone)T4 and T3 levelsThyroid antibodies (particularly in autoimmune diseases such as Hashimoto's or Graves')Imaging studies like ultrasound or thyroid scans to evaluate the shape of the gland.A fine-needle aspiration biopsy in some instances may be done to test for unusual lumps or nodules.Types of Thyroid DisordersIt's essential to highlight the range of thyroid disorders that often go unnoticed until routine tests reveal them. According to Dr. Anil Menon, HOD of Endocrinology at DPU Super Speciality Hospital, Pimpri, Pune, “The spectrum of thyroid disorders spans Hypothyroidism (less functioning) to Hyperthyroidism (more functioning), with the former being more common. Despite being a common disorder, the symptoms of hypothyroidism overlap with everyday complaints such as fatigue, hair fall, constipation, and weight gain. Many times, patients may have no symptoms at all and the condition is discovered incidentally during routine testing.”Although hypothyroidism is the most prevalent thyroid disorder in the U.S., occurring in about 1 in 20 individuals, it's far from the only one. Here's a quick overview of the range:Hypothyroidism: Underactive thyroid; causes slowed metabolism, weight gain, fatigue, and depression.Hyperthyroidism: Overactive thyroid; produces fast metabolism, weight loss, anxiety, and rapid heart rate.Thyroid cancer: Usually occurs as a neck nodule or swelling and can be treated with surgery and/or radioactivity.Untreated hypothyroidism can cause severe complications, such as goiter, infertility, heart disease, and in extreme cases, myxedema, an unusual life-threatening disorder. However, thyroid hormone replacement therapy, most often levothyroxine, can successfully replace hormone levels and symptoms.Dr Anil adds that while hypothyroidism often goes unnoticed, “Hyperthyroidism tends to be spotted earlier due to noticeable symptoms like unintentional weight loss, irritability, increased sweating, and in some cases, eye protrusion seen in Graves’ disease.” Thyroid patients should collaborate closely with an endocrinologist to keep their hormone levels in check and modify medications accordingly. Fatigue, weight gain or loss, mood swings, and even the slightest vision or digestive changes must never be dismissed. Thyroid hormone changes do not always come on dramatically, but their effects can be immense. The solution lies in early detection, prompt diagnosis, and regular management.If you have reason to believe your thyroid is responsible for a change in your health, see a healthcare practitioner. In this day and age, where there can be such influence on endocrine function from stress, dietary shifts, and the environment, being proactive about your thyroid status is one of the best investments you can make in your health.