A Prospective Study on the Outcome of Pre-Prandial versus Post- Prandial Thyroid Function Tests


  • Sumesh Raj Sree Gokulam Medical College and Research Foundation Trivandrum, India
  • Mohammed Ramees Sree Gokulam Medical College and Research Foundation Trivandrum, India
  • Prasanth Prasad Sree Gokulam Medical College and Research Foundation Trivandrum, India


Hypothyroidism, Fasting, Postprandial


The values of Thyroid stimulating hormone (TSH) are generally observed to be more in the fasting than in the postprandial state. This study aims to evaluate whether TSH and free T4 measured in fasting and postprandial state would show any difference which is of statistical significance. A total of 180 patients were divided into 3 groups, which consisted of equal number of euthyroid, subclinical and hypothyroidism patients. Serum TSH and free T4 were collected both in the fasting and postprandial state. TSH values were found to be significantly lower after food when compared to fasting in all the three groups and this result was found to be statistically significant. The significant decline in TSH values postprandially in comparison to fasting values, might lead to inappropriate diagnosis and management of patients, especially sub clinical hypothyroidism.


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