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If You're Tired, Try This First.

Updated: Jul 8

Some very obvious causes of fatigue can be fixed directly, but you have to go looking for them and figure out if any of them apply to you. Here are some factors to rule out at home or with your doctor.


Start here if you're tired all the time.

Causes of Tiredness You Can Find With Lab Tests


Your doctor should check these simplest, obvious causes of fatigue, but you should start supplementing before you get to the "abnormal" range. So the ideal range for your thyroid or iron levels, is more narrow than the range that indicates disease. Often, people experience symptoms when things are technically normal, but heading in the wrong direction. Providing your body with more of what it needs in those grey areas where your numbers aren't out of range, but also aren't ideal, can often be beneficial.


  • Iron deficiency anemia - Iron deficiency is a classic cause of fatigue that almost everyone is aware of. It can be tested by looking at the size of your red blood cells, as well as how red they are. The redness is caused by iron, and it's measured in a test called hematocrit. One thing your doctor might not think to test is your ferritin level, which is long-term iron storage. If your red blood cells are on the small side, or if they're a bit more pale than they should be, or if your ferritin is on the low end of the range, then iron supplementation might help. Symptoms of iron deficiency include fatigue, pale skin, gums or inside of eyelids, craving for ice, shortness of breath, restless legs at night, fast heartbeat, dizziness or lightheadedness, and sore or inflamed tongue. If you're having symptoms within the normal range, or if your red blood cells are normal but your ferritin is low-normal, it could be worth supplementing for a month to see if you feel better. Here is a deeper dive on ferretin. The focus there is on making babies, but the discussion about iron levels is relevant.


  • B12 deficiency or pernicious anemia - Vitamin B12 deficiency can be caused by a lack of good sources of B12 in your supplements or diet, but gene SNPs such as MTR and MTRR can also play a part. The symptoms resemble those of other conditions we are listing here, including fatigue, weakness, numbness, increased heart rate, and irritability. Your doctor will also look at the size of your red blood cells as a screening tool because without B12, red blood cells become overly large. Additionally, vitamin B12 levels can be directly tested in the serum. The fix for this is usually a simple B12 supplement; however, if the B12 deficiency is actually a more complex problem, known as pernicious anemia, it can be more challenging to treat. Pernicious anemia is an autoimmue disorder in which the immune system attacks intrinsic factor, which is necessary for B12 absorption. This requires medical intervention.


  • Low thyroid or other thyroid disorders - A complete thyroid work-up should be done by an endocrinologist and includes TSH, T3, and T4 hormone levels, and often thyroid antibodies. The basic screening test your doctor is likely to run is called a TSH, or thyroid-stimulating hormone, and the normal range in the US is 0.4 to 4.0 mlU/L (milli-international units per liter). Nutritional support for thyroid function can be added even if the TSH is within normal range but above 2.0 mlU/L. Thyroid support usually includes minerals important to the thyroid such as zinc, selenium, and iodine, as well as tyrosine which is a precursor to thyroid hormone.


  • Blood Sugars Imbalance - Blood sugar is one of the most common factors I see in fatigue that often doesn't show up on the simple glucose screenings that doctors do when your blood sugars have historically been in normal range. Regardless of what your blood sugar is on a spot-test, if you have fatigue working to balance your blood sugar through the simple steps in The Glucose Goddess Method by Jesse Inshauspe can make a huge difference to your energy. In fact, that was the number one improvement that her test group reported. This isn't about changing a lab value, it's about changing the way you regulate your blood sugar ups and downs during the day.


  • Sleep Apnea - Most sleep disorders are obvious to the people who have them. The inability to fall asleep or stay asleep is obvious. The one sleep disorder that is often not obvious, at least to the person who has it, is sleep apnea. This disorder happens when something blocks your airway during sleep and your body rouses itself partially in order to start breathing again. Most folks suspect this because of deep fatigue, or if their partner tells them that they snore like a lumberjack, stop breathing in their sleep, or gasp for breath in their sleep. Your doctor will test this with a sleep study, either in a specialized clinic or with a unit you can take home overnight. There are a variety of treatment options, but the most common is a CPAP machine, which you wear while you sleep.


  • Major Illness - If you have fatigue and also a variety of other symptoms, it is important to talk with your doctor to do a thorough diagnostic workup because fatigue is the first symptom of everything, and we don't want to miss a major illness like diabetes, autoimmune disease, or cancer.


Less Common Causes of Fatigue (If You're Tired, Try This First)


These are the causes of fatigue that you can either notice or investigate on your own. These may take some detective work on your part, but finding the cause of your fatigue is 100% worth it. If you're tired, try this first before you start with prescription drugs or medications.


  • Sleep stuff - Outside of apnea, this won't take detective work at all. You know if you're not sleeping, but it is still amazing to me how many people come to talk to me in a one-on-one consult, looking for the cause of their fatigue, who only sleep five hours per night. This is the obvious thing you need to work on and we will have several episodes dedicated to this issue.


  • Carbon Monoxide poisoning - Slow leaks of carbon monoxide in your house or workplace can lead to symptoms that are vague and difficult to trace. Especially when the leak is extremely slow and symptoms build slowly over time. Fatigue, weakness, shortness of breath, memory loss or confusion, nausea and vomiting, chest pain, and rapid heartbeat can all be signs. If any of these symptoms sound familiar, have your carbon monoxide tested in your home or install a carbon monoxide alarm, which is similar to a smoke alarm. Also, there are testing services that can test your home or place of business. The only way to fix this is to eliminate the excess carbon monoxide, so it is important to test, and your MD might not think of it.


  • MTHFR - The most reported symptom by people with the MTHFR mutation is fatigue. Other symptoms that can be associated with MTHFR are anxiety, depression, repeated miscarriages, blood clots, hormone imbalance, chronic pain for unknown reasons, seasonal allergies, and sleep disturbances. If any of this is ringing alarm bells for you, you have two options. You can always treat yourself as if you have MTHFR and go through the steps because there is no harm in them, even if you don't have an MTHFR polymorphism. You can also use an at-home genetics test like 23andme.com or ancestry.com, and then download your raw data and run it through the Methylation panel at geneticgenie.org. This will provide you with a wealth of valuable information about your genes and highlight a few potential causes of fatigue.


  • Tooth Infection - If you have fatigue and pain or discomfort in a particular tooth, it is important to talk with your dentist about the possibility of a tooth infection. Infections can happen deep around the roots of your teeth, and they are hard to detect and even harder to treat unless the tooth is removed. I had just such a chronic infection for four years and noticed that my energy steadily declined during that time, although my dentist wasn't able to find the infection until my tooth cracked. Once the tooth was removed, my energy rebounded within a couple of weeks.


  • Too many life demands - Only you can take a good look at your life and tell whether or not you have too much on your shoulders. Being overextended is never going to give you extra energy. This links in with adrenal fatigue and the health of your adrenal glands.


  • Acute illness - Having a viral or bacterial infection makes you tired no matter what. It's easy to try to push through with cold medicine and sheer grit, but until you give your body some rest and get over the illness, you will be fatigued. I'd suggest a day or two off.


If you know someone who is feeling tired, share this post with them. Sharing is caring.

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Please Read: The information here is for educational purposes only. Please consult with your primary care physician before making changes to your diet, supplements, or pharmaceutical medications. If you are having a medical emergency, please call 911. Your life and health are precious.

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