We recommend Thyro-Boost be used anytime the thyroid is on the lower end of “normal” levels or below normal levels. Often doctors will say you are “fine” because you fall in the normal range, but when you check the actual values you are on the low end of normal. In this case you WOULD benefit from Thyro-Boost. We do NOT recommend using it if you are on the higher end of normal or if you are HYPER-thyroid.