Folic acid deficiency: when there is a lack of vitamin B9

Folic acid (also known as folate or vitamin B9) is an essential water-soluble vitamin from the B complex group, necessary for the maturation of structural proteins and hemoglobin (and thus, indirectly, red blood cells). Its deficiency in humans is not uncommon today due to nutritional gaps in diets based on industrially processed foods.

Folic acid is effective in treating certain types of anemia and pellagra. Unlike other water-soluble vitamins, folic acid is stored in the liver. Additionally, it works with vitamin B12 and vitamin C to help the body break down, use, and create new proteins. Folic acid also performs other important functions in the body, such as assisting in the formation of red and white blood cells and contributing to DNA production, the fundamental building block of the human body that carries genetic information.

Folic acid deficiency is defined by low levels of this vitamin in the blood, and its symptoms include:

• Fatigue, irritability, or diarrhea
• Insufficient growth
• Smooth and sensitive tongue

If untreated, folate deficiency can lead to:

• Anemia (low red blood cell count)
• Low levels of white blood cells and platelets (in severe cases)

When a person has anemia caused by folic acid deficiency, red blood cells become abnormally large. This condition is known as megaloblastic anemia.

Pregnant women need to ensure adequate folic acid intake, as this vitamin is crucial for the development of the spinal cord and brain of the fetus. Folic acid deficiency can cause severe congenital abnormalities known as neural tube defects. The Recommended Dietary Allowance (RDA) of folate during pregnancy is 600 micrograms (µg) per day.

The main causes and risk factors for folic acid deficiency include:

• Diseases that affect folic acid absorption in the digestive system (such as celiac disease or Crohn’s disease)
• Excessive alcohol consumption
• Overcooked fruits and vegetables, as folic acid is easily destroyed by heat
• Hemolytic anemia
• Certain medications (e.g., phenytoin, sulfasalazine, or trimethoprim-sulfamethoxazole)
• Diets lacking sufficient fruits and vegetables
• Kidney dialysis

Folic acid deficiency is typically diagnosed through a blood test that measures serum levels of this vitamin.

Treatment involves the oral administration of folic acid. In patients with absorption problems, high doses of oral folic acid are usually sufficient to replenish stores.

Folic acid deficiency can be prevented (as with other vitamin deficiencies) by maintaining a balanced diet. Many foods are rich in folic acid, including:

• Beans and legumes
• Citrus juices and fruits
• Dark leafy green vegetables like spinach, asparagus, and broccoli
• Liver
• Mushrooms
• Poultry, pork, and seafood
• Wheat bran and other whole grains