This study used healthy men and women who did not have clinical thyroid problems at the start of the study. Thyroid scores¹ were analyzed based on their trend, meaning it flagged individuals with functional thyroid problems. The study tracked 1864 men and women an average of 12.7 years. It found that women, but not men, who were in the sluggish thyroid category had more than double the risk for developing Alzheimer's disease.

This finding is rather significant as it suggests that even a slightly impaired function of thyroid hormone can really take its toll on mental function as the years go buy – speeding the rate of cognitive decline. More evidence that keeping your thyroid in tip top working order is a really good idea – especially for women.