Are you concerned about your low body temperature?

If my temperature is always below 98.6, is something wrong?

Yes, something could be wrong. But it could also be normal. We'll help you evaluate the most common problem that can cause chronic low body temperature. But lets take a minute to look at what's normal.

For some, low body temperature can be normal

To begin with, almost everyone believes that a 98.6 is a healthy temperature and anything above or below that indicates that something is amiss. The truth, however, is a little different. First, there are individual genetic differences. In a room full of 100 healthy individuals there will be approximately 2 people whose highest temperature of the day will not reach 98. That's normal for them. Surprised? Second, everyone's temperature changes throughout the day. In the morning your temperature will be as much as 1 degree (for some people as much as 1 1/2 degrees) colder than a measurement you might take in the mid to late afternoon.

So, is a chronic low temperature harmless?

No, not if it has decreased over months or years, especially if the change has been accompanied by a change in your body's normal functioning, in other words, you have developed symptoms that aren't normal for you. And to be fair, for some people the change could have taken place so long ago or so gradually that the symptoms and low temperatures seem like they have always been there, although the symptoms might be slowly worsening.

If your normal temperatures are low and are causing you some concern, here are three questions to ask yourself:

Do you have a chronic low body temperature AND body symptoms that are not normal for you, or you've had both as long as you can remember but they aren't common for other people? Maybe a friend has one or two of the same body complaints you do but not the number or the variety of issues you have. Chronic 'abnormal body symptoms' AND 'low temperature' together are warning signs you should certainly pay attention to.
If you know what your temperature typically has been, has it dropped by more than 1/2 degree over months or a number of years? I wasn't sure, so I went to my doctor's office and looked at eight temperature measurements from different office visits before my symptoms appeared.
If you don't know whether your temperature has dropped and don't have a reasonable way to check what normal used to be before you begin to develop symptoms, measure your temperature and compare it to our chart.

Besides genetics, what are the low body temperature causes?

There are a great many possibilities but most of them are very unlikely. The most common low body temperature causes are -- beginning with most likely: low thyroid, diabetes and infection. Low thyroid is by far the most common of the three. The thyroid hormone T3 regulates the temperature of every cell in your body. If there is a decrease in the T3 working efficiently in your body's cells, your temperature will drop and you will develop abnormal body functioning in a surprising variety of places, symptoms which for some people are a nuisance and for others can be debilitating.

Symptoms of low thyroid

We created this website to help you evaluate whether your low body temperature might be low thyroid and a simple way to treat one of its most common causes. Take a look at this comprehensive list of possible symptoms. Do some of these look familiar? There are many causes of a low thyroid but two causes account for 98% of all cases: hidden hypothyroidism and Hashimoto's syndrome. In conversations with doctors who treat hidden hypothyroidism, estimates from the latest research and doctors who have written about it, hidden hypothyroidism might be upwards to three times more common than Hashimoto's syndrome.

What do we suggest you do next?

The term hidden hypothryoidism is probably unfamiliar. Read about where the name hidden hypothyroidism comes from. You'll also find out more information about Hashimoto's syndrome and a way to tell which is most likely the cause of your low body temperature.