Alcohol can affect thyroid function, but the specifics are unclear.
This article goes over the different ways that alcohol might affect your thyroid function.
It also discusses the conditions that can affect your thyroid function and how drinking alcohol might contribute to them.

Verywell / Jessica Olah
These hormones are fueled by iodine, which is used to make thyroid hormones.
Its important to note that these studies are not focused on causation, but rather simple association.
If you have a thyroid condition, you should drink alcohol in moderation.
Heavy drinking may worsen your symptoms.
Can Alcohol Affect Thyroid Medications?
Alcohol is not known to affect the way levothyroxine works.
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National Health Services.Levothyroxine.