What is the interaction between Irish moss (seaweed) and levothyroxine (T4)?

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From the Research

It's generally safe to take sea moss while on levothyroxine, but they should be taken at least 4 hours apart to prevent potential interference with thyroid medication absorption. Levothyroxine should be taken on an empty stomach, typically first thing in the morning, 30-60 minutes before eating 1. Sea moss contains iodine, which is involved in thyroid function, so consuming it later in the day would be advisable. While sea moss offers nutrients like iodine, potassium, and calcium that may support overall health, there's limited scientific evidence for many of its claimed benefits.

Some key considerations for patients taking levothyroxine include:

  • Monitoring thyroid function regularly, with the frequency of testing depending on individual factors such as the stability of thyroid-stimulating hormone (TSH) levels and the presence of underlying conditions like chronic autoimmune thyroiditis 2, 3.
  • Maintaining consistent timing with both medication and supplements to keep thyroid hormone levels stable.
  • Being aware that high doses of levothyroxine (>125 μg/day) may be associated with a higher risk of abnormal TSH levels 3.
  • Recognizing that patients with hypothyroidism may require higher levels of serum free thyroxine to achieve a normal TSH value compared to euthyroid control subjects 4.

Always consult your healthcare provider before adding sea moss or any supplement to your regimen, especially with thyroid conditions, as individual responses may vary and your medication dosage might need adjustment based on how your body responds 5.

References

Research

Monitoring Thyroid Function in Patients on Levothyroxine. Assessment of Conformity to National Guidance and Variability in Practice.

Experimental and clinical endocrinology & diabetes : official journal, German Society of Endocrinology [and] German Diabetes Association, 2017

Research

Optimal free thyroxine levels for thyroid hormone replacement in hypothyroidism.

Endocrine practice : official journal of the American College of Endocrinology and the American Association of Clinical Endocrinologists, 2008

Research

Hyperthyroidism: A Review.

JAMA, 2023

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This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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