Is your metabolism low? Maybe you are one of the many people that say that they have a low metabolism. But how can you know for sure? One way is to see if you exhibit some of the signs of a low metabolism. This includes having chronic low energy and feeling cold, particularly in your hands and feet. Another way is to take some simple measurements to make an assessment of your metabolism at home. In this article I will describe two basic tests to determine whether you have a low metabolic rate.
The information I share in this article is inspired by the work of researchers such as Broda Barnes and Ray Peat. These guys were way ahead of their time and really were the forerunners of the “pro-metabolic” movement. I have learnt a lot from reading these guys work along with others who have shared or built on their theories such as Danny Roddy, Matt Stone, Keith Littlewood and Emma Sgourakis. I will link other peer-reviewed sources of information at the bottom of this post. Definitely check those out if you are interested in reading more into the science behind low metabolism.
Link between low metabolism and thyroid function
The underpinning theory is that your metabolic rate is driven by your thyroid function. A sluggish thyroid results in a “slow metabolism” otherwise known as hypothyroidism. Conversely, an over-active thyroid means a fast metabolism, aka hyperthyroidism. For optimal health and wellbeing, you want your thyroid to be functioning in the healthy range. By this I mean it is producing normal amounts of thyroid hormones which are being used appropriately by your cells.
Dr Denis Wilson, claimed that of every 100 patients with a low body temperature and hypothyroid symptoms, only 5 will show up as having abnormal TSH levels and therefore a diagnosis of hypothyroid (1). He labeled this condition of low metabolism symptoms with normal thyroid test results as Wilsons Temperature Syndrome. I have to make clear that this is not an accepted diagnosis according to most medical professionals. However, I view it alongside Adrenal Fatigue as a description of a common adaptive state of the body functions which leads to particular symptoms.
Perhaps the diagnosis is not accepted but if the “treatment” works then I don’t see it as a problem. Interestingly enough, both low metabolism and adrenal fatigue are linked to stress! But we won’t go there for today. We will quickly review the common signs and symptoms of a low metabolism. Then I will introduce you to the two tests you can take an home to answer the question, is your metabolism low?
Signs and symptoms of low metabolism
To clarify, symptoms are health effects identified by the individual whereas signs can be observed and measured by others. Often experiencing symptoms like fatigue and low energy can be frustrating. This is because you are made to believe by doctors and those around you that it is “all in your head”. There are many symptoms related to a low metabolism and often they go unnoticed because they are subtle or seen as normal.
Broda Barnes in his book Hypothyroidism: The Unsuspected Illness*, argued that many common symptoms are a result of sub-clinical hypothyroidism. Some of the symptoms associated with a low thyroid function are fatigue, headaches, depression, anxiety, low libido, constipation, low mood, PMS, insomnia and easy weight gain (1). If you are experiencing several of these symptoms on a regular basis, potentially you are dealing with a low metabolism.
Two major signs of a low thyroid function and low metabolism are low body temperature and low pulse rate. These two signs are consistently associated with the symptoms above. Other signs include dry skin, dry hair and slow growing or brittle nails. All of the signs and symptoms are a result of reduced cellular respiration and energy generation.
Now let’s see, is your metabolism low?
Low metabolism test 1: Basal body temperature
Broda Barnes pioneered low basal body temperature as a sign of hypothyroidism, aka a low metabolism. Therefore, the first of the two tests to see if you have a low metabolism is to measure your temperature. Do this upon waking every day for a week and record your results. You can use any thermometer just make sure to warm it up first to avoid skewing your measurements.
A healthy functioning metabolism should result in an oral temperature of 36.6°C or above (armpit temperature is usually approx. 0.3-0.6°C lower). If your temperature is consistently below this, it may be a sign of a low metabolism (2). Especially if you also have some of the signs of a low metabolism I described above and in my previous post. Remember, this is your temperature upon waking. After eating, drinking and moving your body, your temperature should increase above this minimum.
For females, it is also important to know that your basal body temperature can increase by up to 0.5°C following ovulation (3). It then then decreases again once menstruation begins. This is due to an increase in metabolic rate during the luteal phase of your menstrual cycle. The numbers above refer to your temperature in the first half of your cycle so make sure you do the test before ovulation for an accurate assessment. As a side note, observing this temperature rise is a good sign that you are ovulating which is a good sign of a healthy menstrual cycle and fertility.
Low metabolism test 2: Resting pulse rate
The second test you can use to determine whether your metabolism is low is to measure your resting pulse rate. Measuring heart rate is a well established method for determining metabolic rate (4). A pulse rate of 70-85 beats per minute (bpm) is generally an indicator of a healthy metabolism. The exact number range differs but there is agreement in the pro-metabolic world that a pulse rate of 60bpm or below is a sign of low metabolism. Especially when combined with low temperature and other signs of low thyroid function.
Although many health professionals state that a pulse rate of 60bpm or lower is a sign of fitness, this is not the whole truth. Yes, it is true that athletes have a low pulse rate as a result of their fitness. However, fitness and health do not always go together! A low pulse rate, or bradichardia is a sign of metabolic adaptation. That is a modification of the metabolic processes in order to do more with less energy input. This is a useful adaptation in athletes as it allows them to perform at a higher level in sport. But it says nothing about their general health.
For example, many female athletes suffer from the Female Athlete Triad which is a combination of low energy availability, disrupted menstrual cycles and decreased bone mineral density (5). Usually this is a stress state caused by too much exercise and not enough energy intake. Although it has athlete in the title, this can happen to any woman who is very active and not fueling correctly. This happened to me and I did not have a menstrual cycle for 8 years! Although I was physically fit, my metabolism was extremely low and I had lots of health issues.
But isn’t a high pulse rate unhealthy?
It does get a little complicated as a study published in a peer-reviewed medical journal concluded that increasing resting heart rate is associated with increased incidence of metabolic syndrome (6). According to the NHS, metabolic syndrome is “the medical term for a combination of diabetes, high blood pressure (hypertension) and obesity”. However, as the study did not look in detail at participants diet and activity, we cannot know whether those with a high resting heart rate were also following a pro-metabolic lifestyle (unlikely in my opinion).
Having a high temperature and pulse rate whilst eating well and being active is different than achieving the same outcome by being sedentary and eating unhealthy food. Really, more research is needed to differentiate between these two. Perhaps now that pro-metabolic lifestyle is gaining interest online, there will be more research done. Until then, the best thing to do is keep an eye on your other health markers such as blood pressure, glucose and weight alongside your temperature and pulse to find the lifestyle that works best for you.
How to increase a low metabolism
If you try out these two tests and think that you have a low metabolism, what can you do about it? I shared some simple tips for how to speed up a a slow metabolism in a previous post. In that post I also describe some of the potential causes of a low metabolism so make sure you check it out. You can also try incorporating my top foods to increase your metabolism into your daily diet. I will be making more detailed posts on this topic so if you are interested, make sure to follow my blog to receive updates by email. You can also like this post and comment below to let me know!
*If you purchase the book through this link I will earn a small commission through Amazon Affiliates (you will not be charged extra)
Over to you…
- Comment: Did you take the tests? Is your metabolism low? What are your thoughts?!
- Like this post and share to support my business
- Follow my blog for more posts on nutrition, yoga and holistic health