
3 nutrient deficiencies that can worsen fatigue in people with Ehlers-Danlos and Joint Hypermobility Syndromes
The most common symptom associated with nutritional deficiencies is fatigue. Because it’s very common for people with Ehlers-Danlos Syndrome (EDS) and Joint Hypermobility Syndrome to experience fatigue, nutritional deficiencies often go undiagnosed. As a registered dietitian who works primarily with patients that have Ehlers-Danlos Syndrome and Joint Hypermobility Syndrome, I think it’s crucial to identify nutritional deficiencies that can make patients experience excessive levels of fatigue.
The three most common deficiencies that can cause fatigue for anyone, including patients with connective tissue disorders, are vitamin D, vitamin B12, and iron.
If you have Ehlers-Danlos Syndrome (EDS) or Joint Hypermobility Syndrome and fatigue, it’s worth looking into potential deficiencies to see if they’re contributing to your symptoms. The good news is that when nutritional deficiencies are addressed, symptoms usually improve within a few weeks to months.
Vitamin D Deficiency and Fatigue
Having adequate levels of vitamin D is crucial for a variety of reasons, including supporting bone and muscle health. While research on why exactly vitamin D deficiency contributes to fatigue is ongoing, current evidence suggests that a potential explanation could include skeletal muscle cell dysfunction which can result in muscle weakness.
Vitamin B12 Deficiency and Fatigue
Multiple scenarios can cause anemia, a condition that affects the development of red blood cells. When red blood cells do not form correctly, their ability to deliver the right amount of oxygen to other cells in the body is impaired. This can lead to fatigue.
B12 deficiency can cause issues with cell division throughout the body, including red blood cells. This can result in megaloblastic anemia, a condition that eventually leads to fewer total red blood cells available to grab oxygen from the lungs and deliver it to other body cells.
Iron Deficiency and Fatigue
Iron deficiency can also lead to a different type of anemia. Oxygen directly binds to the iron within hemoglobin molecules in red blood cells. Without enough iron available for the development of healthy red blood cells, unhealthy red blood cells will not be able to pick up enough oxygen from the lungs and deliver it to cells around the body. This leads to symptoms of fatigue. People with iron deficiency anemia will also likely have a harder time being active since their muscles are not getting the oxygen they need to function optimally.

How do I know if I’m deficient in one of these nutrients?
The best way to determine if you have a vitamin D, vitamin B12, or iron deficiency is by asking your doctor to order blood tests for you. These tests are generally very accurate and are the best way to identify and diagnose these three deficiencies. Your doctor might order blood tests that analyze more than just these three nutrients to see other aspects of how nutritional deficiencies can be affecting your body. For example, serum iron (the amount of iron circulating in the blood) is rarely tested by itself. Often, doctors order blood tests that also analyze how much hemoglobin is in red blood cells, how many red blood cells are present, and what the average size of red blood cells is. These tests give dietitians and doctors more information about what exactly is happening in the body. Plus, your doctor might order additional tests to rule out other scenarios that might be leading to fatigue.
Once you get the results, talk to your doctor and dietitian about them. Sometimes, results might come back as “normal” but higher or lower levels might actually be better for you. Your doctor or dietitian can help you determine what your individual goals are based on your current symptoms and medical history.
I have a vitamin D, vitamin B12, or iron deficiency…now what?
If blood work indicated that you had a deficiency in one of these nutrients, you will need to follow the advice of your doctor or dietitian to get your levels back to normal. The fastest way to correct deficiencies is by using vitamin or mineral supplements, however, these need to be treated with caution. Your doctor or dietitian will recommend the right form of the nutrient and the right dose of the nutrient so that you can avoid potential side effects and harm from over-supplementation. Your doctor or dietitian can also recommend specific foods that can help you get more of the nutrient you are deficient in.
How can people with Ehlers-Danlos Syndrome prevent nutritional deficiencies?
People with Ehlers-Danlos Syndrome often struggle with eating enough, eating limited diets, and having frequent digestive issues. These can all lead to missing out on getting enough nutrition.
Are you struggling with GI symptoms like nausea, bloating, or constipation? Learn more about Ehlers-Danlos Syndrome and gut health in my course Oh My GI! It’s the perfect overview for patients who feel confused and overwhelmed about tummy troubles.
Click here to learn more.
People with Ehlers-Danlos Syndrome should work with a dietitian to help get relief from the symptoms that hold them back from eating enough nutritious foods to maintain adequate nutrition status. Plus, a dietitian can assess your average nutrient intake and identify gaps that can lead to deficiencies in the future.

Why supplement safety matters
Supplement safety is critically important. While it’s easy to purchase supplements of all kinds online and in stores, this does not mean that they are harmless. Supplements can lead to vitamin and mineral toxicity if taken in too large of doses, taken for too long of a time period, or if taken without having an existing deficiency.
Talk to your doctor or dietitian before starting a new supplement or if you are unsure if you should continue taking a supplement.
Summary
People with Ehlers-Danlos Syndrome and Joint Hypermobility Syndrome often experience fatigue. They might experience excessive levels of fatigue if they have a deficiency in vitamin D, vitamin B12, or iron. Their symptoms may improve when appropriately addressed with supplementation recommendations from their healthcare providers.
Have you had an iron, vitamin D, or B12 deficiency before? Let me know in the comment section if you think this impacted your symptoms and if addressing them helped.
Interested in getting help from a registered dietitian with your EDS symptoms? Connect with me here.