Mar 20, 2025
Dealing with Constant Fatigue? 6 Biomarkers Might Tell You Why
Feeling constantly drained, even when you try to rest? Your body could be sending deeper signals.
It can be really upsetting when heavy tiredness just won't go away, even after you've slept enough. We often blame things like staying up late, feeling stressed, or not eating well. While those things matter, sometimes the reasons for feeling so tired are not so clear.
Luckily, there are biomarkers that tell us why we have persistent fatigue. They could show us imbalances that make you feel so tired all the time, giving us clues beyond the usual reasons and maybe leading to better ways to help.
Understanding Fatigue: More Than Just Feeling Sleepy
That constant fatigue that just won't lift, even with rest, sometimes turns into chronic fatigue. This means feeling tired for six months or longer, along with other problems besides just being sleepy. Unlike normal tiredness, severe fatigue messes with your daily life and might not have an obvious medical reason.
In fact, 3.3 million people in the United States experience myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). And more than 9 in 10 people with ME/CFS have not been diagnosed.
Common chronic fatigue symptoms include extreme tiredness that doesn't get better with rest, brain fog, sore muscles and joints, headaches, sore throat, and swollen glands. What makes it difficult to diagnose is that there is no specific test for ME/CFS. But the causes of severe fatigue might have to do with our immune system, hormones, how our bodies make energy, or even infections.
Body Clues: Biomarkers and Fatigue
Our bodies are fascinating, and when things are a little off, they often leave little breadcrumbs. Here are a few of those biomarkers that can be checked to understand why you might be feeling so tired:
Cortisol
Think of cortisol as your body's main "stress responder." It helps us get going in the morning and deals with tough situations. But if you're constantly stressed, your cortisol levels are all over the place.
It's either too high for too long, which wears you out, or even too low if your body gets a bit overwhelmed. When you wake up, your cortisol levels usually give you a little boost. However, this boost is different if you often feel tired.
Testosterone
While often linked to men, testosterone plays a role in energy and muscle strength for everyone. If your levels dip, you might feel more fatigued. And get this: the balance between testosterone and cortisol is also important, especially if you’re active. When your cortisol is always high and your testosterone level is low, it could be a sign that your body is under a lot of strain.
C-Reactive Protein (CRP)
CRP is a marker that goes up when there's inflammation in your body. High levels of inflammation don't tell us exactly what is causing the problem, but they are a sign that a health issue might be making you feel tired.
Vitamin D
You’ve probably heard Vitamin D called the "sunshine vitamin" because our bodies make it when our skin gets some sun. But lots of people, especially those in places with less sun or who are indoors a lot, don’t get enough of it.
If you’ve been feeling tired, you might want to get your Vitamin D levels checked with a quick blood test. Fixing a Vitamin D deficiency helps boost your energy.
Iron
Iron is an important mineral that transports oxygen all around your body. It's a big part of hemoglobin, a protein in red blood cells that carries oxygen from your lungs to your tissues.
When your iron levels drop too low, your body struggles to make enough healthy red blood cells. This leads to a condition known as iron deficiency anemia. A common sign of this is feeling really tired or weak, like you just don’t have any energy. If you're concerned about your iron levels, a simple complete blood count (CBC) test checks for this condition.
HbA1c
The HbA1c test is a good way to see your baseline blood sugar levels over the past couple of months. A regular blood sugar only shows your levels at that moment. But HbA1c gives you a better view of how well your body manages sugar over time.
If your blood sugar is often too high, like with prediabetes or diabetes, your body struggles to use that sugar for energy, leaving you feeling tired. Plus, your body has to work extra hard to handle high blood sugar, which wears you out. A low blood sugar also makes you feel weak and dizzy.
So, if your HbA1c levels are higher than they should be, it might mean your blood sugar isn’t in the best range, affecting your energy levels. This test is mainly for checking diabetes, but even slightly high results can make you feel tired.
The Big Picture: It's Not Just One Thing
So here’s the deal: there isn’t just one magic test that explains tiredness for everyone. Feeling drained can come from a bunch of different things, and what affects one person might not even touch another. Your body, your habits, and several other factors all play a part. That’s why, if you’re feeling worn out all the time, it’s a good idea to talk to a doctor and get all the necessary fatigue blood tests.
What Can You Do When Fatigue Hits Hard?
Feeling wiped out all the time is no fun, but there are things you can do to boost your energy. Here are some simple tips:
Prioritize Sleep Like It's Your Job: It sounds basic, but getting enough good sleep is really important. Aim for 7 to 9 hours of sleep each night. Create a relaxing bedtime routine, keep your room dark and cool, and try to stick to a sleep schedule, even on weekends.
Pay Attention to What You Eat: What you eat directly impacts your energy levels. Focus on eating whole foods like fruits, vegetables, lean proteins, and whole grains. Don't forget to drink plenty of water. Try to limit processed foods and sugary drinks because they can make you crash later.
Move Your Body Gently: It might seem weird to exercise when you’re feeling tired, but light activities like walking, swimming, or yoga help. Start slow and build up as you feel up to it.
Manage Stress Mindfully: Chronic stress is a major energy zapper. Try finding ways to relax, like meditation, deep breathing, or spending time outdoors. Engaging in hobbies you love can also help you feel better.
Talk to Your Doctor About Bloodwork: If you're still feeling drained despite making changes, it might be a good idea to talk to your doctor. They can check if something else is going on, like a vitamin deficiency or hormonal issue, by doing some blood work for fatigue. Get a complete blood panel from Mito Health to check more than 100 markers, including cortisol, testosterone, and HbA1c.
Your Fatigue Matters: Finding the Reasons Why
Feeling tired all the time is common and real. It often goes beyond simply needing to go to bed earlier. Our bodies are complex, and paying attention to small signs can help us understand what’s happening.
If you've been feeling fatigued for more than 6 months, it's a sign you're chronically fatigued. Talk to your doctor and get all necessary tests to find out the real cause of why you feel so drained.
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