Vitamin B2 is also known as riboflavin. Riboflavin is a water-soluble vitamin that is found in most animal and plant tissues. The word “ribo” comes from ribose, which is a sugar, and “flavin” means “yellow.” Riboflavin is absorbed in the small intestine and what little is stored in the body is stored in the liver, kidneys, and heart. On the other hand, like most water-soluble vitamins, any excess intake is excreted in urine. Since riboflavin is a yellow compound, excess riboflavin in the urine will make it turn bright yellow.
What Does It Do?
The simple explanation for riboflavin is that it is involved in the creation of energy for the body, normal cell function and growth, supports adrenal functioning, and helps maintain a healthy nervous system.
The more complex answer is that riboflavin is involved in oxidation-reduction (redox) reactions in the body. During these redox reactions, it exchanges hydrogen atoms instead of exchanging electrons. The coenzyme forms of the vitamin are FMN (flavin mononucleotide) and FAD (flavin adenine dinucleotide). As FMN, riboflavin moves along hydrogen atoms into the electron transport chain for energy production for the body. As FAD, riboflavin is involved in the breakdown of fatty acids. Other FAD-containing enzymes help form the vitamin B6 coenzyme, synthesize an amino acid (tryptophan) into niacin (vitamin B3), and participates in folate metabolism (vitamin B9). Riboflavin is also involved in the cell’s antioxidant defense system. As you can see, riboflavin is a very busy vitamin!
Where Can You Find It?
Approximately 25% of our dietary riboflavin intake comes from dairy products. The remainder normally comes from enriched flour, eggs, and meat. Foods high in riboflavin include liver, oysters, plain yogurt, Brewer’s yeast, mushrooms, spinach and other leafy green vegetables, broccoli, asparagus, lean ham, low fat and fat-free milk, and cottage cheese. Riboflavin can be broken down when exposed to light, so you’ll notice that milk and milk products as well as enriched flour and cereals are usually packaged in paper or plastic cartons.
How Much Do You Need?
The RDA for riboflavin is shown below:
Infants & Children:
Birth – 6 months 0.3 mg
7 – 12 months 0.4 mg
1 – 3 years 0.5 mg
4 – 8 years 0.6 mg
9 – 13 years 0.9 mg
Boys: 14 – 18 years 1.3 mg
Girls: 14 – 18 years 1.0 mg
Men: 19 years and older 1.3 mg
Women: 19 years and older 1.1 mg
Pregnant women 1.4 mg
Breastfeeding women 1.6 mg
What Happens If You Don’t Get Enough?
A deficiency of riboflavin can lead to inflammation of the tongue (glossitis), cracking of tissues around the mouth (cheilosis), seborrheic dermatitis (a skin disease), inflammation of the mouth (stomatitis) and throat, various eye disorders such as blurred vision, nervous system disorders, confusion, and headaches. Riboflavin deficiency may also worsen cancer, certain types of cardiovascular diseases and diabetes. People who do not drink milk or eat milk products should be careful to get enough riboflavin in their diet.
Alcoholics are at risk of riboflavin deficiency because they generally eat a diet deficient of most vitamins. Long-term use of phenobarbital may also lead to riboflavin deficiency as the drug breaks down this vitamin in the liver.
What Happens If You Take Too Much?
Since riboflavin is a water-soluble vitamin, is seems that there is no adverse effects from excesses of this vitamin. Therefore, there is no Tolerable Upper Limit. Like most water-soluble vitamins, any excess is excreted in urine.
The best way to consume any nutrient in order to avoid under-consumption is to consume a wide variety of foods, in a wide variety of colors, and eat according to MyPlate.
Until next time, remember that… there are no excuses when it comes to your health!