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How Nutrient Deficiencies Deplete Energy Levels

Kate Rhéaume, ND

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There are many causes of fatigue, from lack of sleep to elevated stress levels. Dietary nutrient deficiencies may also contribute to tiredness.* Unfortunately, a healthy diet is often one of the first things to go when we are stressed and overworked. Let’s talk about why nutrient support is more important than ever!*

Iron Deficiency

Iron is required for the formation of hemoglobin, which the red blood cells use to carry oxygen. Iron deficiency can cause fatigue. If there is not enough iron, there is not enough hemoglobin, resulting in less oxygen to power the muscles and brain.

Dietary iron can be found in animal sources (meat, fish, and poultry) and plant sources (raisins, prunes, beans, tofu, and leafy greens). [1] The animal sources contain heme iron, and the plant sources contain non-heme iron. 

While heme iron is more easily absorbed, absorption of non-heme iron can be supported by consuming it with citrus foods and away from dairy products. Food sources of non-heme iron also often contain phytate, which inhibits iron absorption. The impact of phytate can be minimized by soaking grains and legumes before cooking.

Vitamin B12 Deficiency

B12 may also support healthy energy levels.* Vitamin B12 is vital for healthy red blood cells, though in a different way than iron.* As with iron, B12 deficiency can contribute to fatigue due to less oxygen powering the muscles and brain.

Vitamin B12 can be found in meat, poultry and fish, as well as dairy and eggs. [2] Vegans can experience B12 dietary deficiencies, but vegans can look for plant based sources of B12, including nutritional yeast, fortified foods, and B12 supplements.

Magnesium Deficiency

Magnesium deficiency is a lesser-known cause of fatigue, but it makes sense when we think about its actions in the body. One of the functions of magnesium is to enable cells to make and store ATP.* If we don’t have enough magnesium, cellular energy production decreases, causing fatigue.*[3] Foods high in magnesium include nuts, brown rice, and leafy greens. [4]

Vitamin C Deficiency

While extreme vitamin C deficiency is known to cause scurvy, it is less well known that mild to moderate deficiency can contribute to fatigue.*[5] Vitamin C is a cofactor in the synthesis of carnitine, which is needed to transport fatty acids into the mitochondria where it helps with energy production.*[6] Because of this, vitamin C deficiency can result in carnitine deficiency, which results in decreased energy production and may contribute to fatigue. Vitamin C can be found in kiwi, citrus fruits, strawberries, bell pepper, broccoli, and others. [7]

Eating a healthy, varied diet [8] and addressing nutrient deficiencies may help reduce fatigue and support optimal energy levels.* Next time you’re tired, think about feeding your cells nutrients to help with energy instead of reaching for coffee. 

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  1. Linus Pauling Institute. Iron. 2020. Accessed December 13, 2020.
  2. Linus Pauling Institute. Vitamin B12. 2020. Accessed December 13, 2020.
  3. Tardy AL, Pouteau E, Marquez D, et al. Vitamins and minerals for energy, fatigue and cognition: A narrative review of the biochemical and clinical evidence. Nutrients. 2020; 12(1):228. 
  4. Linus Pauling Institute. Magnesium. 2020. Accessed December 13, 2020.
  5. Linus Pauling Institute. Vitamin C. 2020. Accessed December 13, 2020.
  6. Adeva-Andany MM, Calvo-Castro I, Fernández-Fernández C, et al. Significance of l-carnitine for human health. IUBMB Life. 2017; 69(8):578-94.
  7. Linus Pauling Institute. Vitamin C. 2020. Accessed December 13, 2020.
  8. Canada's Food Guide. 2020. Accessed December 13, 2020.
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Dr. Rhéaume is a graduate of the Canadian College of Naturopathic Medicine.

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