Using the Basal Body Temperature to see if you’re hypothyroid.

March 27, 2013 | by

Hypothyroidism is one of the most commonly unrecognized conditions that people face today. By some estimates, up to 40% of the population may be subclinically hypothyroid. Thyroid hormone is a little bit like “how fast is the engine revving?” — too little, and you have trouble with energy, losing weight, sluggishness and a number of other physical signs and symptoms. Too much, and you may have trouble gaining weight and experience muscle wasting.

Because simple lab values can be misleading, it’s very important to consider the clinical picture of symptoms to see if your thyroid gland is underperforming and preventing you from optimal health and happiness.

One way to do this is to check your Basal Body Temperature. This the temperature of your body as soon as you wake up. Here’s how to do it:

  1. Get a glass or Mercury based thermometer for the readings. You’ll want to shake it down and put it by your bedside as you go to sleep. You’ll want to sleep alone so that your body doesn’t pick up heat from your spouse (you can still be in the same bed).
  2. Upon awakening, place the thermometer underneath your armpit for 10 minutes and record the temperature.
  3. Check the basal body temperature for 3 – 5 consecutive days. Women who are still menstruating should check the temperature on the first 3 days of their period. Men and post-menopausal women can check it at anytime. Women who still have at least one ovary after a hysterectomy should check for 14 days and average the lowest 3 temperatures.
  4. Normal basal body temperature is between 97.8 and 98.2 Fahrenheit. While levels between 97.6 and 98.0 are a little bit of a grey area suggesting hypothyroidism, levels below 97.6 are stronger in suggesting a low functioning thyroid.

It’s important to note that the body temperature does help the diagnosis, but in no way rules-in or rules-out hypothyroidism. But it’s an easy test to do right away if you have any suspicions of being hypothyroid. It can also help with managing therapy once you get your baseline.

In another post, I’ll describe some of the symptoms of hypothyroidism.