Fundamentals of Human Nutrition/Riboflavin

< Fundamentals of Human Nutrition

8.2 RiboflavinEdit

8.2.1 SourcesEdit

8.2.2 FunctionsEdit

The water-soluble vitamin Riboflavin, also known as B2, functions in energy metabolism, as an antioxidant, as a coenzyme in many areas, and in redox reactions. Like other B vitamins, riboflavin helps the body convert carbohydrates, fats and proteins into glucose for fuel for the body. In energy metabolism riboflavin is in its coenzyme forms of flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) and functions as a hydrogen/electron carrier. Riboflavin also works in combination with some other B vitamins, B6 and folate, in a process in the body that changes these into useable forms. Riboflavin is essential in growth processes and red blood cell production as well.

The electron transport chain is explained in a series of five complexes, of those complexes FMN functions in complex I and FAD in complex II. In the electron transport chain, FAD serves as an electron carrier and accepts electrons to become FADH2. FADH2 then gives its electrons to complex II of the chain that forms ATP molecules that act as energy.

Riboflavin also serves as an antioxidant that is used as a defense by the body to neutralize free radicals and prevent them from multiplying and causing cell and DNA damage. Antioxidants donate electrons to the unstable free radicals making them neutral and therefore unable to harm the body.

Because of its vital functions, riboflavin has medical implications and is used in an attempt to treat some ailments. Riboflavin supplementation may be beneficial in the treatment of migraine headaches, riboflavin deficiency, high homocysteine levels, and cataracts.

• Migraines: Riboflavin cannot reduce the pain or duration of the migraine but may be effective if taken at 400 mg/day in reducing the number of migraine headaches. 
• High homocysteine: People who suffer from hyperhomocysteinemia, or high amount of homocysteine in the blood, may find taking supplemental riboflavin to be beneficial in lowering the levels. Some people are unable to convert homocysteine into the functioning amino acid form methionine used by the body and therefore suffer from high levels of homocysteine in the blood. Taking riboflavin has shown in studies to help lower homocysteine blood levels in people with this condition.
• Cataracts: Because of riboflavin’s function as a coenzyme in bodily processes it has been seen as an effective supplement in the reduction of cataracts. Riboflavin, in combination with       the other B vitamins, helps to promote healthy vision and without all the B vitamin components, vision processes will be impaired. Because the combination of B vitamins is needed for normal vision, riboflavin supplementation will be most useful in combination with a niacin supplement in reducing a person’s chance of developing cataracts.==8.2.3 Requirements==

8.2.4 DeficiencyEdit

As stated earlier riboflavin or vitamin B2 is fundamental in the process of metabolism in all the macro-nutrients. More specifically it plays an important role during the step of energy release from carbohydrates, proteins, and fats. This same energy is what is used to contract the muscles, power the cells, generate new cells, fight of bacteria. Based on this knowledge, it is clear to see that a deficiency in riboflavin would be completely detrimental for overall body health. Some of the symptoms that would mark a riboflavin deficiency include:

-Pale Skin

-Bloodshot eyes

-Sensitivity to light


-Itching and burning of eyes

-Oily skin

-Dull hair

-Sore tongue

-Cracked lips

-Premature Wrinkling

-Inflammation in the mouth

-Split Nails

-Lesion formation

Organ failure will begin with the adrenal glands, whose job is to secrete and metabolize hormones with enzymes. These hormones spur on many major bodily functions, without the energy to drive or make more enzymes the adrenal gland fails to dispense out the hormones in the bloodstream (Riordan). Vitamin B2 deficiency is commonly linked to alcoholism, dietary inadequacy, and people with blood disorders.

The most common of the causes, is dietary inadequacy. For example, in Kwashiokor and Marasmus disease in which there is insufficient protein and energy intake, they may too lack in essential B vitamins, including riboflavin (Von Castel-Roberts). As it is necessary for basic biological function it is common in plants and animals. When we consume them, we absorb their vitamin B levels as well. Seeing as our entire food system comes from plants and animals, riboflavin is not a scarce vitamin (Vitamin B Complex). Watch out for elderly folks whose primary source of calorie is tea and toast. People with infections, liver disease or are severe alcoholics are also prone to deficiency.

Vitamin B2 supplements should be taken in quick response to low levels to keep important bodily functions going. The daily recommended dietary allowance is 1.3 to mg for adult men, 1 mg for women, 1.1 for pregnant women, and 1.6 for breastfeeding women (Von Castel-Roberts). For adults with low levels of riboflavin, treatment dosage should be at least 5 mg daily and no more than 30 mg daily, all in divided doses. Simply eating at least the recommended amount of riboflavin, which can be reached by following the example in “myfoodplate” attains many benefits. Cataracts in the eyes can be prevented. Reduction of homocysteine levels in the blood, by converting it into methionine. And for serious migraine issues, taking high doses of riboflavin (about 400 mg) reduces the number of attacks (Riboflavin).

8.2.5 ToxicityEdit


"Riboflavin." Riboflavin. Web. 22 Aug. 2015.

Riboflavin (vitamin B2) deficiency. (n.d.). Retrieved October 23, 2015.

Riordan HD, Mikirova N, Taylor PR, Feldkamp CA, Casciari JJ. (2012). The Effects of a Primary Nutritional Deficiency (Vitamin B Study). Food and Nutrition Sciences, Vol. 3 No. 9

Vitamin B Complex , Robinson, Frank Alfred, 1874-1951.

"Vitamin B2 (Riboflavin)." University of Maryland Medical Center. Web. 22 Aug. 2015.

Von Castel-Roberts, Kristina. (2015) Water-soluble Vitamins. University of Florida. McCarty Hall C Auditorium, Gainesville, Fl. Lecture.

Whitney, E., & Rolfes, S. (2002). Understanding nutrition (9th ed.). Belmont, CA:Wadsworth.