Experts: Mediterranean-style diet can ease symptoms of thyroid disease but won’t replace treatment

Dietary changes, particularly a Mediterranean-style eating pattern, can help ease symptoms experienced by people with thyroid disease, British health experts say — but food is not a substitute for medical treatment.

Thyroid disorders, which impair the butterfly-shaped gland at the base of the neck, affect about one in 20 people in the U.K. An underactive thyroid, or hypothyroidism, typically causes fatigue, weight gain, constipation and cold sensitivity, while an overactive thyroid, or hyperthyroidism, produces weight loss, sweating, itching and palpitations. Both conditions generally require diagnosis and medication, yet clinicians say diet can play a supportive role.

Hannah Belsham, a physiologist at the Nuffield Trust, and other clinicians recommend a Mediterranean-style approach: plenty of fruit, vegetables, whole grains, lean proteins and healthy fats. They say that nutrients including selenium, zinc, iodine, iron, calcium and vitamin D — found in nuts, seeds, oily fish and lean meats — support overall health and can be particularly relevant to people with thyroid disorders.

Pharmacist and nutritionist Deborah Grayson cautioned that people with hyperthyroidism should monitor their iodine intake because high levels of iodine can exacerbate an overactive gland. She noted that dairy products can be a significant source of iodine and that reducing intake may help some patients with hyperthyroidism.

General practitioners also emphasised the importance of avoiding ultra-processed foods and excess stimulants. Dr. Nirusha Kumaran advised patients to limit sweets, chocolate, cakes and high caffeine consumption, saying these items can promote inflammation and aggravate thyroid symptoms. Dr. Asia Ahmed, who works with private health-testing firm Medichecks in addition to practising in the NHS, warned that alcohol can also worsen symptoms.

Research supports links between modern dietary patterns and thyroid health. A 2022 study found heavy consumption of ultra-processed foods was associated with an increased risk of thyroid problems, and separate studies have connected ultra-processed diets to higher rates of obesity, cardiovascular disease, type 2 diabetes, some cancers and premature death. A recent major study published last month also found that a Mediterranean diet combined with exercise, calorie management and weight-loss support reduced the risk of type 2 diabetes by about one-third among nearly 5,000 obese adults followed for three years.

Clinicians stressed that diet alone will not cure thyroid disease. Several foods and supplements can interfere with the absorption of thyroid medications, they said. Calcium and iron supplements, coffee, walnuts, high-fibre meals and calcium-fortified juices may reduce drug absorption; patients are generally advised to take thyroid medication on an empty stomach and wait at least 30 minutes before eating.

Despite medical caveats, social media platforms have proliferated with “thyroid-friendly” recipes and claims of dietary cures. Some users report benefits from cutting gluten or dairy, while viral posts promote nutrient-dense snacks such as a concoction of mashed mackerel, avocado and seaweed. Clinicians say such recipes can provide relevant nutrients, but evidence that specific elimination diets cure thyroid disease is lacking.

Thyroid disorders are much more common in women than men, with women about 10 times more likely to be affected. Many cases arise from immune system dysfunction: Hashimoto’s disease involves immune destruction of the thyroid leading to underactivity, while Graves’ disease involves immune stimulation that causes overactivity. Public figures including model Gigi Hadid and television presenter Kate Garraway have publicly discussed living with thyroid conditions, and musician Missy Elliott has described the effects of Graves’ disease on daily functioning.

The range of symptoms can delay diagnosis for months or years. Some patients discover the problem after unexplained tiredness, sudden weight changes or mood shifts; others learn of a thyroid condition only after noticing hair thinning during routine salon visits. Though thyroid cancer is far less common — about 3,900 people in the U.K. receive a diagnosis each year — clinicians say most patients with fatigue or weight change are more likely to have hypothyroidism or hyperthyroidism than cancer.

Doctors hope increased public interest in diet and thyroid health will prompt more people to seek evaluation for unexplained symptoms. "Food alone won't fix a broken thyroid," Dr. Kumaran said, "but good nutrition can make living with one far easier."

Clinicians recommend that anyone experiencing persistent fatigue, unexplained weight change, palpitations or hair loss discuss symptoms with a GP, who can order blood tests to measure thyroid hormone levels and antibodies and advise on treatment, monitoring and appropriate dietary adjustments.