Subclinical hypothyroidism, that I call low-grade hypothyroidism, effects a large percentage of the world population and is much more common in women than men and its most common cause is an immune system attack on the thyroid gland. I call it low-grade hypothyroidism instead of subclinical hypothyroidism because “subclinical hypothyroidism” means that this low thyroid condition has no bad clinical consequences, which is inaccurate. The term subclinical was introduced to the medical community in the 1960’s and has been used since. Since then, many research studies have shown that low-grade hypothyroidism effects cholesterol levels, contributes to cardiovascular disease, promotes weight gain and even metabolic syndrome when untreated, effects cognition, mood and anxiety levels, reproductive functions, and generally speaking, effects your quality of life.
Other research studies have not clearly demonstrated such benefits. Because of the negative studies published over the years, the controversy as to whether doctors should prescribe thyroid medications to patients affected by low-grade hypothyroidism has persisted and continues to confuse practicing physicians.
It is true that many of the symptoms and effects of low-grade hypothyroidism are not caused by the balance itself and may be related to autoimmunity when Hashimoto’s thyroiditis is the underlying condition causing the low-grade hypothyroidism. But very likely low-grade hypothyroidism does cause symptoms and bad effects. From my extensive experience dealing with this condition, I can tell you that you may not have any symptoms today while suffering from low-grade hypothyroidism, but you may have symptoms and bad effects down the road. You also need to know that if you have low-grade hypothyroidism and you are dismissed by your physician, you may slip into a more severe state of hypothyroidism down the road.
Many of the studies that have shown no benefits of treating low-grade hypothyroidism have used the conventional levothyroxine therapy that most doctors use to treat hypothyroidism. The results in these studies might have been different if an appropriate, well-balanced T4/T3 treatment had been prescribed to these patients.