Diet Plan for Overactive Thyroid

Hyperthyroidism or overactive thyroid occurs when the thyroid gland produces an excess of thyroid hormones thyroxine (T4) or triiodothyronin (T3), which makes the body's functions speed up. Symptoms include weight loss, shakiness and anxiety.

Hypothyroidism is an underactive thyroid – see here.

T3 and T4 control how quickly the body burns energy and how quickly reactions in the body happen. Metabolic rate affects lots of things, such as body weight, and how much you sleep. The hormones speed up the body's metabolism, causing processes in the body to happen faster. The production of the thyroid hormones is controlled by another hormone called thyroid stimulating hormone (TSH), secreted from the pituitary gland in the head.

Hyperthyroidism has many different symptoms relating to the speeding up of your body's metabolism. The main symptoms are:

• Nervousness, irritability or over-emotional behaviour
• Tremor and shakiness
• Poor sleeping
• Intolerance to heat and perfuse sweating
• Weight loss despite increased appetite (some people gain weight due to eating more)
• Tiredness
• Muscle weakness
• Raised heart rate and palpitations
• Infrequent menstruation (periods) or problems getting pregnant
• Increased bowel movements – possibly loose stools / diarrhoea
• Shortness of breath, especially when exercising
• Hair loss / finer hair
• Swelling of the thyroid gland in the neck (goitre)
• Red and swollen eyes with double vision

Graves' disease is an autoimmune disease and is the most common cause of hyperthyroidism. Antibodies mimic the activity of TSH causing the thyroid gland to produce too much T3 and T4. Nodular thyroid disease is another common cause where small lumps or nodules within the thyroid gland form. Abnormal thyroid tissue within these nodules produces too much thyroid hormone. Hyperthyroidism can also be due to thyroid inflammation following a viral infection or if you take too much medication that contains iodine (eg amiodarone used to treat irregular heart beats).

Drug treatment for an overactive thyroid is with beta-blockers and/or anti-thyroid drugs to suppress production of T3 and T4, but careful control is needed to prevent the thyroid from becoming underactive. In more extreme cases the thyroid surgery is needed to remove all or part of the thyroid.

Dietary treatment is based around providing adequate nutrition for energy and weight control. Many people with hyperthyroidism lose weight, but they do have a good appetite. A few however experience a ravenous appetite to such an extent that the actually gain weight, despite the increased metabolism. In both cases, however, a varied diet is needed and one which provides appropriate macronutrition for energy. Any regimen should be based around regular amounts of low glycaemic carbohydrate (see info here) foods which will help regulate poor energy levels. See our Glycaemic Index Tables for GI values of foods.

The following example meal plan has been designed for someone with hyperthyroidism for good nutrition and weight maintenance. Portion sizes will vary depending on your weight goal, but use the plan as a general guide for food choices.

Exercise will also help as it will improve mood. However do not overdo exercise, small regular bouts of gentle cardiovascular work is advised, say 20 minute sessions.

Caffeinated drinks like tea and coffee should be avoided, as caffeine may worsen jitteriness; something which needs to be controlled.

Like all plans, the one below is merely an example and portions sizes will need to be adapted to suit an individual's activity level, own lifestyle, daily routine and nutritional requirements. Use this to give you an idea of which healthy nutritious foods should be included, and don't forget to vary your food choices and to drink plenty of water through the day.