Did you know that iodine deficiency affects nearly 2 billion people worldwide? Despite living in an age where access to nutritious foods should be easier than ever, many communities still lack iodine-rich foods. Even in places where food variety is sufficient, poor dietary choices or misconceptions about “healthy eating” can lead to deficiencies.
Iodine is essential for producing thyroid hormones, regulating metabolism, supporting cognitive function, and ensuring healthy pregnancies. Since the human body cannot produce iodine on its own, we must get it through diet. The recommended daily intake is 150 µg for adults, 220 µg for pregnant women, and 290 µg for breastfeeding women.
What Is Iodine Deficiency?
Iodine deficiency occurs when your body doesn’t receive enough iodine to produce thyroid hormones. This leads to an underactive thyroid (hypothyroidism) and, in many cases, goiter (swelling of the thyroid gland).
Common Symptoms in Adults
Iodine deficiency can reveal itself in subtle ways, often linked to low thyroid hormone levels. Some of the most common symptoms include:
Unexplained weight gain
Persistent fatigue
Muscle weakness and joint pain
Increased sensitivity to cold
Constipation
Thinning, dry, or brittle hair
Dry skin
Puffy face
Slow heart rate
High cholesterol levels
Heavy menstrual bleeding
Brain fog and poor memory
Low mood or depression
Symptoms in Infants and Children
Iodine deficiency in babies and children can be more severe, affecting growth and development. Signs may include:
Learning difficulties
Growth delays
Late tooth development
Weak muscle development
Delayed puberty
Constant sleepiness
Swelling of the face and tongue
Frequent airway blockages
Chronic constipation
In pregnancy, iodine deficiency can increase the risk of miscarriage, complications, and developmental delays in the baby.
Long-Term Health Risks
If untreated, iodine deficiency can lead to more serious conditions, such as:
Chronic hypothyroidism
Heart disease and increased risk of heart attack
Impaired cognitive function
Peripheral neuropathy (nerve damage in hands and feet)
Infertility or irregular menstrual cycles
Complications during pregnancy
Depression and reduced mental clarity
Causes and Risk Factors
The leading cause of iodine deficiency is inadequate intake of iodine-rich foods. While iodized table salt has significantly reduced the global prevalence, risk factors remain:
Limited access to fish, seafood, and red meat (often due to cost)
Restrictive diets that exclude iodized salt (e.g., “specialty” salts that don’t contain iodine)
Pregnancy and breastfeeding (when iodine needs increase significantly)
Diagnosis
Healthcare providers typically diagnose iodine deficiency through:
Urine tests (measuring iodine concentration)
Blood tests (TSH and thyroid hormone levels)
Ultrasound (to check thyroid gland size if abnormalities are suspected)
How to Support Iodine Levels
The good news is, iodine deficiency is treatable. You can support your iodine intake by including:
Iodized table salt (in moderation)
Fish and seafood
Seaweed
Eggs
Dairy products
Red meat
In some cases, healthcare providers may recommend iodine supplements, often in the form of potassium iodide. However, supplements should only be taken under medical supervision—too much iodine can overstimulate the thyroid and trigger autoimmune reactions.
Iodine may be a small mineral, but its impact on the body is enormous—from thyroid health to fertility and cognitive development. Supporting your iodine intake through diet (and supplements if needed) can help prevent the wide range of complications associated with deficiency.
Remember, balance is key: both too little and too much iodine can cause health issues.
