Nutrition
Thyroid disorders
Diet does not treat thyroid disease, but timing of medication, iodine and a few interactions genuinely matter.
What you are aiming for
- Take levothyroxine correctly so it is absorbed
- Get adequate but not excessive iodine
- Manage weight changes realistically alongside treatment
- Support bone and heart health where thyroid levels are over-treated
Build meals around
- Iodine from ordinary sources: iodised salt, dairy, fish, eggs
- Selenium sources such as fish, eggs, brazil nuts (a couple, not a handful)
- Adequate iron, calcium and vitamin D from food, taken away from thyroid medication
- A balanced diet with enough fibre — constipation is common in hypothyroidism
Limit or avoid
- Kelp and high-dose iodine supplements, which can worsen thyroid disease
- Calcium, iron and antacids within four hours of levothyroxine
- Very large quantities of raw goitrogenic vegetables (cabbage, kale) if iodine intake is low — cooking reduces the effect
- Excess caffeine and alcohol in hyperthyroidism, where they worsen symptoms
Meal timing
- Take levothyroxine on an empty stomach, 30–60 minutes before food, or at bedtime well after eating.
- Keep the timing consistent day to day.
- Separate soya, coffee, calcium and iron from the dose by at least four hours.
Portions
- Normal balanced portions; there is no special thyroid diet.
- One to two brazil nuts a day is plenty for selenium — more can be harmful.
A sample day
- On wakingLevothyroxine with water only
- Breakfast (1 hour later)Eggs with wholegrain toast
- LunchFish with salad and potatoes
- SnackYoghurt and fruit
- DinnerChicken with vegetables and rice
Common myths
“Going gluten-free treats thyroid disease.”
Only relevant if you also have coeliac disease, which is more common in autoimmune thyroid disease — get tested rather than assuming.
“Iodine supplements boost a sluggish thyroid.”
Excess iodine can trigger or worsen both under- and overactive thyroid disease.
Treatment-related challenges
- Weight change is often modest once treated; expectations need to be realistic.
- Absorption problems from coeliac disease, gastric surgery or other medications.
- Hyperthyroidism raises energy needs substantially until it is controlled.
See a registered dietitian if
- · Thyroid disease with coeliac disease or diabetes
- · Significant unexplained weight change
- · Pregnancy with thyroid disease
Afya Companion offers education and self-help support. It does not diagnose, treat or replace care from your doctor, nurse, psychologist or dietitian. If something in your health changes, speak to your care team.