The Relationship between Fish Intake and Urinary Trimethylamine-N-Oxide

Area of Science:

• Nutritional biochemistry
• Biomarker discovery
• Human nutrition

Background:

• Accurate assessment of dietary fish intake remains a significant challenge in nutritional research.
• Fish consumption is linked to various health benefits, necessitating reliable intake measurement methods.

Purpose of the Study:

• To identify reliable biomarkers for fish intake.
• To investigate the relationship between fish intake biomarkers and key health parameters in a free-living population.

Main Methods:

• The NutriTech study involved participants consuming controlled fish quantities, with urine analyzed via NMR spectroscopy.
• Trimethylamine-N-oxide (TMAO), dimethylamine, and dimethyl sulfone were identified as potential biomarkers.
• Cross-sectional analysis in the National Adult Nutrition Survey assessed biomarker-derived fish intake correlations.

Main Results:

• Urinary TMAO, dimethylamine, and dimethyl sulfone exhibited a significant dose-response relationship with fish intake (p < 0.05).
• Fish consumption led to a greater increase in urinary TMAO compared to red meat.
• Correlations between TMAO, fish intake, and calculated fish intake were poor (r = 0.148 and r = 0.142, respectively).
• TMAO positively correlated with serum insulin and insulin resistance in males, particularly those with high dietary fat intake.

Conclusions:

• Urinary TMAO demonstrates a strong dose-response with fish intake.
• However, TMAO alone is inadequate for accurately quantifying fish intake in free-living populations.
• Further research is needed to refine fish intake biomarkers and understand TMAO's metabolic implications.