A disease that affects one in 20 people and is notoriously difficult to diagnose is being highlighted by experts. The condition, which often presents with "mild" symptoms, can go unnoticed for years, with research indicating it takes an average of 4.5 years for a diagnosis to be made.

Approximately 3.3 million people in the UK suffer from thyroid problems, with women six times more likely to be affected than men. However, identifying thyroid issues can be challenging due to their symptoms often mirroring those of common illnesses.

Research conducted by the University of Aberdeen revealed that it typically takes 4.5 years for a thyroid condition to be diagnosed. The study analysed data from nearly 1,200 patients' experiences, from the onset of symptoms through to diagnosis, treatment, and beyond.

While the average time for a thyroid condition diagnosis is 4.5 years, it was found to be "considerably longer" for patients suffering from hypothyroidism. In most instances (almost two thirds of respondents), multiple appointments and a worsening of symptoms were required before a diagnosis was reached, reports The Mirror.

The 2023 study's researchers discovered that the condition has significant implications for the physical, mental, and emotional wellbeing of those affected. The report indicated that thyroid patients are at a higher risk of experiencing long-term sick leave and impaired working ability.

So, what exactly is the thyroid, and what signs should you watch for? And when is it time to consult a doctor?

Your thyroid is an important endocrine gland that produces and releases specific hormones, according to the Cleveland Clinic.

It explains: "Your thyroid's main job is to control your metabolism - how your body uses energy. Sometimes, your thyroid doesn't work properly. These conditions are common and treatable."

Thyroid disease serves as an umbrella term for disorders that impact how your thyroid operates. Hypothyroidism and hyperthyroidism represent the two primary forms of thyroid disease.

However, they each have multiple potential causes. Thyroid diseases can be managed - typically through medication.

The two principal forms of thyroid disease are hypothyroidism (underactive thyroid) and hyperthyroidism (overactive thyroid). They each have several disorders that can trigger them including Hashimoto's disease, Iodine deficiency, Graves' disease and thyroid nodules.

The Cleveland Clinic outlines there are numerous signs of the condition. However, it warns: "Unfortunately, symptoms of a thyroid condition are often very similar to the signs of other medical conditions and stages of life. This can make it difficult to know if your symptoms are related to a thyroid issue or something else entirely."

There are two primary categories - those linked to excessive thyroid hormone levels (hyperthyroidism) and those connected to insufficient thyroid hormone levels (hypothyroidism).

The clinic explains: "The symptoms are often "opposites" between the two conditions. This is because hyperthyroidism speeds up your metabolism, and hypothyroidism slows down your metabolism."

Symptoms of hypothyroidism include:

• Slower-than-usual heart rate.
• Feeling tired ( fatigue ).
• Unexplained weight gain.
• Feeling sensitive to cold.
• Dry skin and dry and coarse hair.
• Depressed mood.
• Heavy menstrual periods (menorrhagia).

Symptoms of hyperthyroidism include:

• Faster-than-usual heart rate ( tachycardia ).
• Difficulty sleeping.
• Unexplained weight loss.
• Feeling sensitive to heat.
• Clammy or sweaty skin.
• Feeling anxious, irritable or nervous.
• Irregular menstrual cycles or a lack of periods ( amenorrhea ).

Both conditions can cause an enlarged thyroid (goiter), but it's more common in hyperthyroidism.

The NHS advises you should visit a GP if you suspect you might have either an underactive or overactive thyroid. Whilst some of the signs are commonplace and may be triggered by other ailments, it's crucial to have them examined by a GP.