It is already known that (mainly excessive) drinking increases the risk of cancer. Now it appears that alcohol consumption can lower the risk of thyroid cancer. That is the conclusion of Korean researchers in a meta-analysis that was recently published in the scientific journal Cancer Research and Treatment.
Lower risk
The consumption of alcohol (compared to never or occasional drinking) is related to a lower risk of thyroid cancer. That is the conclusion of the meta-analysis1 that combines the results of 33 observational studies. More detailed analyses show that the relation mainly applies for the North-American region. The type of thyroid cancer, sex, and the type and amount of alcohol make no difference.
Biological mechanism
The researchers describe two possible mechanisms that may explain the association between alcohol intake and the risk of thyroid cancer. First, alcohol could decrease the levels of ‘thyroid-stimulating hormone’ (TSH). High concentrations of TSH in the blood are associated with higher rates of thyroid cancer. Next to that, alcohol has a toxic effect on thyroid cells. Therefore, the thyroid volume is reduced which might lead to a decreased risk of thyroid cancer. Further research is required to confirm the exact mechanism behind the association between alcohol and thyroid cancer.
In perspective
Previous studies found inconsistent results on the association between alcohol intake and the risk of thyroid cancer. This meta-analysis indicates that alcohol intake lowers the risk of thyroid cancer. The researchers warn that the findings should not be used as recommendation for alcohol intake.