Vitamin B2 (Riboflavin)

Overview

Vitamin B2 (Riboflavin) is a heat-stable, water-soluble vitamin essential for the body’s energy production, metabolic functions, and cellular health. It plays a key role in converting carbohydrates, fats, and proteins into glucose, which the body uses for energy. In addition to its metabolic role, Riboflavin acts as a powerful antioxidant, supporting immune function, maintaining healthy skin, hair, and vision, and protecting cells from oxidative stress.

Vitamin B2 exists in different forms in the body:

1. Vitamin B2 – physiologically inactive
2. Flavin Mononucleotide (FMN) – active form
3. Flavin Adenine Dinucleotide (FAD) – active form

FMN and FAD are critical coenzymes involved in electron transfer, fatty acid metabolism, oxidative deamination of amino acids, and other redox reactions. Vitamin B2 is also essential in the metabolism of folate, Vitamin B12, and Vitamin B6, and helps regulate plasma homocysteine levels, which are linked to cardiovascular disease, pregnancy complications, and cognitive impairment.

Normal plasma levels vary between 4–24 µg/dL (106–638 nmol/L). Riboflavin status can also be assessed through 24-hour urinary excretion, where values <27 µg/g creatinine indicate deficiency.

Symptoms

Vitamin B2 deficiency leads to a range of systemic symptoms due to impaired energy metabolism and compromised cellular repair processes.

Common Symptoms (From the PDF):

1. Fatigue and slowed growth
2. Digestive disturbances
3. Cracks and sores at the corners of the mouth (Angular stomatitis)
4. Cheilosis
5. Swollen, magenta-colored tongue
6. Eye fatigue
7. Light sensitivity
8. Swelling and soreness of the throat

Severe Deficiency Symptoms:

1. Hair loss
2. Hyperemia
3. Skin disorders
4. Itchy, red eyes
5. Reproductive problems
6. Degeneration of the liver
7. Degeneration of the nervous system
8. Anemia and cataracts in advanced cases

Most individuals with Riboflavin deficiency also exhibit deficiencies of other nutrients, and many symptoms reflect combined micronutrient shortages.

Causes

Vitamin B2 deficiency or low plasma levels occur due to inadequate intake, poor absorption, or medical conditions that increase nutrient needs.

Primary Causes (Strictly from PDF):

1. Malabsorption syndrome
2. Chronic alcoholism
3. Liver diseases
4. Life-threatening illnesses
5. Systemic medical conditions

These conditions impair nutrient absorption or increase metabolic demands, leading to Riboflavin depletion.

Additionally, Riboflavin deficiency can impair the body’s ability to metabolize folate, vitamin B12, other B-complex vitamins, and various macronutrients, worsening symptom severity.

Risk Factors

Certain individuals are more likely to develop Riboflavin deficiency due to physiological, dietary, or health-related factors.

Major Risk Factors:

1. Poor Dietary Intake
2. People with low consumption of Riboflavin-rich foods such as milk, eggs, almonds, whole grains, mushrooms, organ meats, wild rice, and leafy greens (as listed in the PDF).
3. Chronic Alcoholism
4. Alcohol reduces nutrient absorption and increases excretion.
5. Malabsorption Disorders
6. Conditions like celiac disease or chronic gastrointestinal illnesses.
7. Liver Disease
8. Since liver stores and activates Riboflavin, hepatic disease affects vitamin status.
9. Severe Illness or Stress
10. Increased metabolic demand depletes Riboflavin reserves.
11. Infants and Growing Children
12. Higher metabolic needs increase risk.
13. Pregnancy and Lactation
14. Increased requirements raise vulnerability to deficiency.
15. Restricted Diets
16. People on limited or unbalanced diets are prone to micronutrient deficiency.

Prevention

Preventing Vitamin B2 deficiency involves proper nutrition, supplementation when necessary, and accurate laboratory monitoring.

Dietary Prevention (From PDF):

Ensure adequate intake of Riboflavin-rich foods such as:

1. Brewer’s yeast, almonds, soybeans
2. Milk, yogurt, eggs
3. Whole grains, wheat germ, wild rice
4. Mushrooms, organ meats
5. Broccoli, Brussels sprouts, spinach

Clinical Prevention Measures:

1. Monitor high-risk individuals including alcoholics, patients with malabsorption, liver disorders, and severe systemic illnesses.
2. Early recognition of symptoms such as mouth sores, magenta tongue, or skin inflammation.
3. Maintain recommended daily intake (RDA):
   1. Adults: 1.3 mg/day (males), 1.1 mg/day (females)
   2. Children vary by age per RDA table in PDF.

Sample Collection & Testing Guidelines:

1. 10–12 hours fasting required before sample collection.
2. Collect 3 mL blood in Na-Heparin or Lithium Heparin tube (green cap).
3. Separate plasma quickly and store in amber-colored containers, protected from light.
4. Send sample frozen.
5. For 24-hour urine testing, use proper collection instructions and acidic preservatives if required.

Analytical Methods:

1. Spectrophotometric assay
2. Microbiological assay