Effect of coffee consumption on thyroid function: NHANES 2007-2012 and Mendelian randomization

Area of Science:

• Endocrinology
• Nutritional Science
• Epidemiology

Background:

• Coffee is a globally popular beverage with largely unknown effects on thyroid function.
• Thyroid disorders, including hypothyroidism and hyperthyroidism, affect millions worldwide.
• Understanding dietary influences on thyroid health is crucial for public health.

Purpose of the Study:

• To investigate the association between coffee consumption and thyroid function markers.
• To determine if coffee intake influences the risk of subclinical hypothyroidism.
• To explore the relationship between coffee and overt hyperthyroidism or hypothyroidism.

Main Methods:

• Utilized data from 6,578 adults (≥20 years) from NHANES 2007-2012 for observational analysis.
• Employed weighted linear and logistic regression models to analyze associations.
• Conducted Mendelian randomization (MR) using genetic data from the IEU database (462,933 European samples) with inverse variance weighting (IVW).

Main Results:

• Consuming 2-4 cups of coffee daily was associated with significantly lower TSH concentrations (b=-0.23).
• Intake of <2 cups of coffee per day showed a reduced risk of subclinical hypothyroidism (OR=0.60).
• No statistically significant associations were found between coffee consumption and risks of hyperthyroidism or hypothyroidism.

Conclusions:

• Lower coffee consumption (<2 cups/day) may decrease subclinical hypothyroidism risk.
• Moderate coffee intake (2-4 cups/day) is linked to reduced TSH levels.
• Coffee consumption appears unrelated to the risk of hyperthyroidism and hypothyroidism.