vitamin B12

your body doesn't make vitamin B12, you have to get it from animal-based foods or from supplements.
Vitamin B12 is required for proper red blood cell formation, neurological function, and DNA synthesis.
Red blood cells carry oxygen around the body using a substance called hemoglobin.
found in a variety of foods, such as fish, shellfish, meat, eggs, and dairy products.
Low levels of B12 can cause:
Anemia and pernicious anemia
Loss of balance
Numbness or tingling in the arms and legs
Weakness
Blood tests and examination of blood cells under the microscope assess haemoglobin levels, the size of red blood cells and the level of vitamin B12 in the blood.

Side-effects and risks. When vitamin B12 is taken at normal doses, side-effects are rare. High doses may cause acne. Allergies to vitamin B12 supplements have been reported and can cause swelling, itchy skin and shock.
Vitamin B12, sometimes called cyanocobalamin, also helps with digestion and heart health, so a deficiency can lead to both digestive disorders and an increased risk for heart disease.
Vitamin B12 is also taken by mouth for memory loss, Alzheimer's disease, to slow aging, and to boost mood, energy, concentration, mental function, and the immune system.

made by: @mehdikh19