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Combining Behavioral Endocrinology and Experimental Economics: Testosterone and Social Decision Making
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S-testosterone decrease after a mixed meal in healthy men independent of SHBG and gonadotrophin levels
M Lehtihet1, S Arver, I Bartuseviciene
1Karolinska Institute, Centre for Andrology and Sexual Medicine, Karolinska University Hospital, Stockholm, Sweden. mikael.lehtihet@ki.se
Andrologia
|April 25, 2012
Summary
Food intake significantly lowers serum testosterone levels by 30% within 60-120 minutes. This finding suggests morning fasting is crucial for accurate testosterone testing and hypogonadism diagnosis.
Area of Science:
- Endocrinology
- Male Reproductive Health
Background:
- Accurate assessment of serum testosterone (S-T), S-LH, and S-SHBG is vital for evaluating testicular endocrine function and diagnosing hypogonadism.
- Testosterone secretion follows a circadian rhythm, peaking in the morning, and is influenced by various factors like diet.
Purpose of the Study:
- To investigate the impact of food intake on serum testosterone, LH, and SHBG levels.
- To determine if post-meal blood draws could lead to inaccurate hypogonadism diagnoses.
Main Methods:
- Serum testosterone (S-T), S-LH, and S-SHBG were analyzed in men after an overnight fast and compared to samples taken 60-120 minutes after a 550 kcal meal.
- Standardized blood collection protocols were employed.
Main Results:
- Serum LH and S-SHBG levels remained unchanged after food intake.
- Serum testosterone (S-T) levels decreased by approximately 30% within 60-120 minutes post-meal compared to fasting levels.
Conclusions:
- Food intake can significantly lower S-T levels, potentially leading to false-negative results in hypogonadism screening.
- For accurate diagnostic purposes, S-T assessment should be performed in the morning after an overnight fast, pending further mechanistic studies.
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