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If you’re waking up tired despite having a good night’s sleep, then you may be experiencing vitamin B12 deficiency.
Vitamin B12 is one of the B complex vitamins that are essential in the body. It is mainly responsible for producing energy in the cells and creating new DNA, and the lack of it can cause extreme tiredness and fatigue. (1)
Symptoms associated with vitamin B12 deficiency
- Fatigue and tiredness
- Pale skin (pallor)
- Jaundice in certain cases
- Nerve disturbances
A doctor will examine you if you experience any of these symptoms and prescribe a suitable vitamin B12 supplement.
How Does Vitamin B12 Deficiency Make You Tired?
Since vitamin B12 is responsible for producing energy, the deficiency causes lesser production of energy from the food you consume and ultimately tiredness.
Vitamin B12 is mainly absorbed through food in the intestines. You may be getting less than the recommended dose of vitamin B12 if: (3)
- You have a type of anemia – A deficiency that causes the improper formation of certain types of stomach cells causing reduced absorption of vitamin B12.
- Dietary deficiency – A lack of vitamin B12-rich foods in the daily diet can lead to vitamin B12 deficiency.
Why Should Vitamin B12 Supplementation Be Included in the Diet?
Some situations and conditions that require the intake of vitamin B12 supplements:
- Gastritis is a condition where there is excessive acid in the stomach that irritates the stomach lining, leading to indigestion and nausea. Gastritis reduces the absorption of vitamin B12 by reducing the factor responsible for its digestion.
- Antacids reduce acid production in the stomach, preventing the release of vitamin B12 bound in food.
- Long-term medication use such as that of metformin can lead to decreased vitamin B12 levels in the body.
- A Helicobacter pylori infection also increases stomach acids and may cause ulcers, which ultimately reduces vitamin B12 absorption from food.
Why Do I Still Feel Tired After Taking Vitamin B12 Supplements?
Vitamin B12 deficiency causes a feeling of tiredness, and supplementation is likely to improve this symptom.
If you continue to experience tiredness, there is likely another underlying reason such as iron deficiency anemia, hypothyroidism (underactive thyroid), sleep apnea, sleep disturbances, chronic stress, or depression that may need evaluation. Consult your doctor to identify the cause.
How to Get Vitamin B12 Through the Diet
Vitamin B12 is present in animal foods such as eggs, animal liver, beef and lamb meat, chicken, and dairy foods. For this reason, vegetarians are more likely to experience vitamin B12 deficiency, and supplements are readily prescribed to manage it. (1)
What Is the Recommended Dosage of Vitamin B12 Supplements?
The recommended daily intake (RDI) for vitamin B12 for people over age 14 is 2.4 micrograms (mcg). In pregnancy, 2.6 mcg, and in the lactation phase, 2.8 mcg. (4)
Are there vegetarian food sources of vitamin B12?
Certain foods are fortified with vitamin B12. Milk and other dairy products are also rich in vitamin B12. Some marine sources such as seaweed or nori may also be rich sources of vitamin B12.
Are there side effects to vitamin B12 supplements?
Excessive vitamin B12 supplementation beyond the recommended dosage can cause headaches, nausea, vomiting, and weakness.
Vitamin B12 is an important water-soluble vitamin that is responsible for the production of energy within the cells and the production of new DNA when cells multiply.
The deficiency of vitamin B12 can occur due to a reduction in absorption, increased acid in the stomach, extremely low acid production, medications such as metformin, and insufficient dietary intake.
Vitamin B12 supplements are commonly prescribed with no side effects.