What is riboflavin?

Riboflavin, also known as vitamin B2, is an essential, water-soluble vitamin from the B complex that plays a central role in energy metabolism, cell protection, and the nervous system. It is a component of important coenzymes involved in energy production, protein and fat metabolism, as well as antioxidant processes.

Riboflavin is heat-stable but is destroyed by light, so it should be stored in opaque packaging. Since the body cannot store vitamin B2, a daily intake through the diet is necessary. Riboflavin is especially active in its coenzyme forms, FMN (flavin mononucleotide) and FAD (flavin adenine dinucleotide) – both essential molecules for the metabolism of every cell in the body.

How does riboflavin work in the body?

1. Energy production (ATP synthesis):
Riboflavin is a key element in the respiratory chain, the central process for generating energy in the mitochondria.
As a component of the coenzymes FMN and FAD, it is involved in the oxidation of glucose, fatty acids, and amino acids and helps convert these nutrients into ATP (adenosine triphosphate) – the body's most important energy source.
A riboflavin deficiency can therefore lead to fatigue, lack of motivation, and muscle weakness.

2. Protection against oxidative stress:
Riboflavin is essential for the activity of the enzyme glutathione reductase, which regenerates the antioxidant glutathione. This protects cells from free radicals and prevents oxidative damage to DNA, proteins, and cell membranes. Vitamin B2 thus contributes to cell health, skin regeneration, and immune system stability.

3. Nervous system support:
As part of numerous enzymatic reactions, riboflavin is important for the function of the central and peripheral nervous systems. It promotes the production of neurotransmitters such as dopamine and serotonin, and contributes to mental clarity and emotional stability.

4. Healthy skin, mucous membranes, and eyes:
Riboflavin is involved in cell division and tissue regeneration, which particularly benefits the skin, hair, nails, and mucous membranes.
A deficiency can cause symptoms such as cracked lips, inflammation at the corners of the mouth (cheilitis), red eyes or flaky skin.
Riboflavin also protects the eye lens from oxidative stress and may help reduce the risk of cataracts.

5. Supporting other vitamins:
Riboflavin is essential for activating other B vitamins, especially vitamin B6 (pyridoxine) and vitamin B3 (niacin). Without enough riboflavin, these vitamins cannot perform their full functions in metabolism.

Benefits of riboflavin

• Promotes energy production and metabolic activity

• Supports cell protection through its antioxidant effects

• Improves skin, hair, and nail health

• Promotes nerve function and mental performance

• Protects the eyes and vision

• Contributes to the activation of other B vitamins

• Supports hormone and protein metabolism

• Reduces tiredness and fatigue

Recommended daily intake

According to the German Nutrition Society (DGE):

• Men: 1.3–1.5 mg per day

• Women: 1.1–1.3 mg per day

• Increased requirements for athletes, pregnant women, breastfeeding women, and people with high energy expenditure.

Since riboflavin is water-soluble, it should be consumed regularly through food - ideally spread across several small meals.

Natural sources of riboflavin

• Milk and dairy products (yogurt, cheese, quark)

• Eggs

• Meat (especially liver, beef, pork)

• Fish (mackerel, salmon)

• Whole-grain products, oatmeal

• Almonds, sunflower seeds

• Green vegetables (broccoli, spinach)

Deficiency symptoms

Riboflavin deficiency (ariboflavinosis) is rare in industrialized countries, but can occur with an unbalanced diet, alcohol abuse, or malabsorption disorders.
Typical symptoms:

• Cracks and inflammation at the corners of the mouth (perlèche)

• Inflammation of the tongue (glossitis)

• Skin problems (dermatitis)

• Sensitivity to light, tired eyes

• Fatigue, difficulty concentrating

• Poor wound healing

Long-term deficiency can impair the metabolism of other B vitamins and weaken the immune system.

Overdose and safety

An overdose is virtually impossible, as excess riboflavin is excreted in the urine – which sometimes causes a harmless yellow discoloration.
Riboflavin is considered very safe and is well tolerated even in high doses.

Conclusion

Riboflavin (vitamin B2) is an essential vitamin for energy, cell protection, and nerve health. It ensures the efficient conversion of nutrients into energy, protects cells from oxidative stress, and contributes to a healthy appearance of the skin, eyes, and mucous membranes.

Adequate riboflavin intake is especially important during physical exertion or increased metabolic activity to support performance, concentration, and recovery. A varied diet including dairy products, whole grains, eggs, and green vegetables reliably meets requirements.

Sources

1. German Nutrition Society (DGE). (2020): Reference values for nutrient intake – riboflavin.

2. Powers HJ. (2003): Riboflavin (vitamin B-2) and health. Am J Clin Nutr, 77(6), 1352–1360.

3. Thurnham DI. (1990): Riboflavin: biochemical and physiological significance. J Hum Nutr Diet, 3(5), 325–333.

4. Pinto JT, Rivlin RS. (2013): Riboflavin (vitamin B2). In: Modern Nutrition in Health and Disease, 11th Ed., Lippincott Williams & Wilkins.