Years ago, when I was in my 20’s, I lived in Jackson Hole and loved snowboarding. My friends and I would go backcountry snowboarding which entailed hiking up the mountains of Teton Pass with our snowboards on our backs to enjoy riding back down through glades of trees, usually in untracked powder. Ah, those were the days! However, I often had a hard time keeping up with my friends’ energy and stamina, especially while hiking up-hill. It felt like my body was stuck in low gear. After doing routine blood work with my doctor, I learned I was iron-deficient. Iron is necessary to deliver oxygen to your body. Not having enough iron, and thereby low oxygen delivery, led to my low physical stamina.
There are many nutrients that help your body make energy. Depletions can leave you feeling fatigued and lethargic, both physically and mentally. Iron and B vitamin deficiencies can impact your energy levels. Read on to learn about the specific testing markers to uncover deficiencies, which foods can help you replete your body, and why you may be low in the first place.
How Does Low Iron Lead to Fatigue?
Iron is a trace mineral that we get from iron-rich foods. It is a component of hemoglobin. Hemoglobin is a protein within red blood cells responsible for carrying oxygen to your tissues and cells. Iron creates heme, a ring-shaped molecule that binds to oxygen. If iron is low the body can’t produce enough hemoglobin and iron deficiency can result. This deficiency causes an insufficient amount of oxygen in your body’s tissues, and you feel fatigued. That fatigue can be felt during everyday activities and especially when trying to exert energy such as exercise.
How to Test Your Iron
Blood work is the best way to know if your iron is low. Ask your doctor or practitioner about ordering the following labs:
- Complete Blood Count – this will include hemoglobin and hematocrit, another red blood cell marker related to iron
- Total Serum Iron
- Total Iron Binding Capacity
- Percent Saturation
- Ferritin – this is the main form of iron storage and can drop before serum iron, hemoglobin or hematocrit levels decrease. Your body tries to maintain a stable amount of iron circulating in your blood, so it will pull from storage first.
Iron-Providing and Iron-Supporting Foods
There are two different types of iron in our food sources: heme and non-heme. Animal-based foods contain heme iron. Plant-based foods and iron-fortified foods contain non-heme iron.
Heme sources are more efficiently absorbed and utilized so they have a greater impact on improving iron status.
- Heme sources: beef, lamb, turkey, chicken, shellfish, sardines, eggs, and organ meats, such as liver
- Non-heme sources: spinach, Swiss chard, lentils, beans, tofu, nuts
Vitamin C foods enhance iron absorption. Many colorful vegetables contain vitamin C such as leafy greens, red bell peppers, broccoli, and carrots. Eating these foods at the same meals as your iron-containing foods can help absorption. Vitamin C is more bioavailable in raw vegetables than cooked vegetables. Cooked vegetables are easier to digest and cooking releases other nutrients, so I always recommend eating a variety of raw and cooked veggies.
Dairy products and caffeine, such as black tea and coffee, can inhibit iron absorption so consume those at a different time of the day.
Chlorophyll, found in green vegetables, is known as a blood builder due to its structural similarity to blood. Wheatgrass and greens powders are good sources of chlorophyll.
Finally, cooking in cast iron pans can increase your iron.
Iron Supplements
Do not take an iron supplement unless your blood work confirms that your iron levels are low. Supplementing iron when not needed can lead to excess iron and oxidative stress. If your blood work shows that you’re low in iron, choose an iron supplement that is gentle on digestion.
- Choose ferrous bis-glycinate or ferrous gluconate forms since they are well absorbed and easy to digest
- Avoid ferrous sulfate as it tends to cause nausea and constipation
Always consult your doctor or practitioner before adding any new supplements.
Why is Your Iron Low?
If your blood work shows low iron levels, investigate the cause to help correct the imbalance. Possible reasons are:
- Low stomach acid from acid blocker medications. Adequate stomach acid is important for absorption of minerals including iron and B12 (more on B12 below). If you have heartburn without the acid blocker medication that will need further investigation as to why you’re having heartburn in the first place.
- Poor absorption through the digestive tract due to gut inflammation from Crohn’s, Celiac, Colitis, IBS, gluten sensitivity, or leaky gut
- Eating a diet low in iron. This is common for vegan diets and some vegetarian diets since the most absorbable and bioavailable form of iron (heme) is from animal-based foods.
- Blood loss from heavy menstrual periods
- Blood loss from surgeries or serious injuries
Low B12 Can Lead to Fatigue
B12 is our largest and most complex vitamin. It has numerous functions throughout the body including several that support balanced energy. B12 plays a role in ATP production which is how your body turns food into energy inside of your cells through a biochemical process called the Citric Acid Cycle. Red blood cells are formed from B12 and folate so, without enough of these vitamins, fatigue can result.
Serotonin, a neurotransmitter which helps sleep, needs B12. Remember poor sleep is a big contributor to fatigue. B12 increases the levels of our body’s most important antioxidant, glutathione. Poor antioxidant status leads to oxidative stress which is another cause of fatigue. B12 also has a very important role in nerve health so symptoms such as numbness and tingling in extremities and neuropathic pain can be linked to low B12.
How B Vitamins Relate to Energy
Along with B12, other B vitamins particularly forms of B1 (thiamine), B2 (riboflavin), B3 (niacin), B5 (pantothenic acid), B6 (pyridoxine), and B7 (biotin) are key nutrients for helping your body convert your food (fats, carbohydrates, and protein) into your body’s energy currency, ATP.
Stacy has written about the energy-producing biochemical steps that use B vitamins in these blogs:
How Nutrition Supports Energy Metabolism
Is the Low Carb Diet Right For You? The Role of Fats in Energy Production
Why Are Your B Vitamins Low?
There is a big relationship between B vitamins, especially B12, and digestion. B12 goes through an elaborate absorption process in the stomach and small intestines and needs conditions of stomach acid to be just right.
- Conditions such as SIBO, gastritis, GERD, heartburn/ reflux, and ulcers can impact B12 absorption
- Acid blocker medications can impact B12 absorption
- SIBO can also impact absorption of other B vitamins
- Vegan diets do not contain B12 since it is found in animal-based foods, so those eating vegan should use a B12 supplement.
How to Test Your B12 and Other B Vitamins
Blood work can look at markers for B12 and folate:
- Complete Blood Count panel contains a marker called Mean Corpuscular Volume (MCV). An increased value can denote low B12 or folate
- Serum B12 and folate
- Methylmalonic Acid (MMA) – this is a marker specifically for B12. When elevated, B12 levels are low.
Organic Acids Profile is a urine test that measures many of the B vitamins and other nutrients related to energy production. More information on Organic Acids testing is available at https://www.bebalancedhealing.com/testing/ and at Diagnostic Solutions Lab https://www.diagnosticsolutionslab.com/tests/organic-acids-profile.
Micronutrient testing from Vibrant Wellness is a comprehensive and specialized blood test that measures B vitamins, fat soluble vitamins, minerals and antioxidants in your blood serum and within your red and white blood cells. More information is available at https://www.bebalancedhealing.com/testing/ and at Vibrant Wellness https://vibrant-wellness.com/tests/nutrients/micronutrient-panel.
Which Foods Contain B12 and Other B Vitamins?
- B12 is found in animal-based foods such as shellfish, beef, bison, lamb, pork, poultry, fish, cheese, yogurt, and organ meats
- Folate (B9) comes from green vegetables, especially leafy greens such as lettuce, spinach, chard, kale, plus beans and legumes
- Thiamine (B1) rich foods are soybeans, brown rice, peanuts, sunflower seeds, brewer’s yeast, oatmeal, spinach, and avocado
- Riboflavin (B2) rich foods are almonds, eggs, leafy greens, Brussels sprouts, mushrooms, soy, organ meats, and wild rice
- Niacin (B3) is in Romaine lettuce, asparagus, cremini mushrooms, spinach, sunflower seeds, tuna, green peas, tomatoes, eggplant, and Brussel sprouts
- Pantothenic Acid (B5) containing foods are shitake mushrooms, avocado, sweet potatoes, lentils, peas, chicken, turkey, broccoli, sunflower seeds, and eggs
- Pyridoxine (B6) containing foods are whole grains (brown rice, quinoa, buckwheat, millet), legumes, beans, sunflower seeds, cashews, hazelnuts, cauliflower, broccoli, asparagus, acorn squash, yams, beef, meat, fish chicken, and turkey
- Biotin (B7) is found in brewer’s yeast, egg yolks, sardines, soy, nuts, legumes, whole grains, cauliflower, bananas, and mushrooms.
B12 and B Vitamin Supplements
If you are interested in supplementing, we recommend taking a B complex since it will contain all the B vitamins and they work in concert with each other. If you have gastric conditions or symptoms you may need to take additional B12 in sublingual or lozenge form for B12 to absorb in your mouth. Always consult your doctor or practitioner before adding any new supplements.
Back to my earlier story. What I didn’t know in my 20s was that I was seriously reactive to gluten. I was eating gluten daily (we lived on inexpensive bagel sandwiches while residing in an expensive ski town) and it was likely creating inflammation in my gut, thereby, impacting my iron and B12 absorption. Looking back, I was probably not eating enough heme iron sources either. My doctor prescribed an iron supplement and I added heme iron with vitamin C foods to my diet. It took a few weeks, but I felt better. A little knowledge can go a long way!
If you’re feeling tired and fatigued, we can help you troubleshoot nutritional imbalances and other possible contributors. Contact us for a free 20-minute consultation.
Resources
Blood Chemistry and CBC Analysis, by Dicken Weatherby ND
National Institutes of Health: https://ods.od.nih.gov/factsheets/Iron-HealthProfessional/
Metabolic Spotlight by Designs for Health
The World’s Healthiest Foods, by George Mateljian