Sluggish Thyroid in Women Increases Heart Disease

Women who have sluggish thyroid function, meaning that they are not hypothyroid by lab test but have many of the symptoms of poorly functioning thyroid and their thyroid scores are close to lower limits of “normal,” have 57 percent increased risk for developing heart disease¹. This relationship does not exist after age 65, which is also an interesting point.

Prior to age 65 the sluggish rate of thyroid function decreases the use of cholesterol by cells everywhere in one's body, with a tendency to leave higher amounts of LDL in the blood longer. Sluggish thyroid is also associated with increased rates of oxidative stress (free radical damage), meaning that the extra LDL is more likely to be damaged and form arterial plaque.

After age 65 it is likely that one's metabolism is slowing down intentionally, partly as a defense or “self-preservation” mechanism. This means that one is likely to live longer. Once older, if thyroid slows down a bit, a faster metabolic pace would cause too much wear and tear and actually speed aging.

Thus, thyroid slowing down a bit in the context of aging is normal. Thyroid slowing down before age 65 is abnormal, and likely to be associated with increased heart disease.