Riboflavin Deficiency in Baltistan (1997; revised Nov. 2008)
H.A. Zappe, S. Nuss, K. Becker, R.H. Schirmer, N. Frey-Rahman

Riboflavin (vitamin B2) is an essential component of the coenzymes flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) which transfer electrons. If there is not sufficient riboflavin in the diet, erythrocytes cannot synthesize enough FAD, the prosthetic group of glutathione reductase and other flavoenzymes. The so-called erythrocyte glutathione reductase activation coefficient (EGRAC) test is based on this fact.

The EGRAC test measures the enzyme activity of glutathione reductase in haemolysate with and without addition of FAD. The ratio of these two activities is a measure for riboflavin deficiency. Not more than 10 µl of blood from the finger tip is needed. The field version of the test takes about 30 min, and it includes the rapid determination of haemoglobin.

Riboflavin deficiency mostly manifests itself at the edge of the mucosa. Frequently, there are painful fissures at the angles of the mouth (perlèche, angular stomatitis), fissures of the lips (cheilosis), an inflammation of the periglottis (glossitis) and a seborrhoic dermatitis of the nasolabial area, the eyelids and the scrotum. Besides, a riboflavin deficiency entails serious risks in fetal development.

Riboflavin is found mainly in food of high nutritional value such as meat, offals, milk, eggs and germs of cereals. Therefore, riboflavin deficiency is always associated with malnutrition or hypo-alimentation. Thus, the EGRAC-test is considered to be a reliable indicator for objectifying a state of malnutrition or concealed hypo-alimentation. Riboflavin is photosensitive and disintegrates when food is dried or stored in open daylight.

In Baltistan, a mountain area around the headwaters of the River Indus in the north of Pakistan, we determined the EGRA-coefficient in 66 women aged 15 to 50. We found an average value of 1.65 (which means that the concentration of free FAD in erythrocytes was 3 to 4 times lower compared to that of European populations). This may be caused by a considerable riboflavin deficiency as livestock breeding is hardly possible in this mountain area and people therefore rarely eat meat. Moreover, cereals are traditionally dried in the open air and are thus exposed to sunlight. Our hypothesis is supported by the fact that the above-mentioned skin diseases occur frequently in Baltistan.

We are planning to confirm our diagnosis by the administration of defined doses of riboflavin and, to try to alter people's traditional diet using an educational program on nutrition. In addition, WHO has announced to support an epidemiological field study which is designed to assess people's dietary health and population situation in the hardly accessible region of Baltistan.

Becker K, Krebs B, Schirmer RH (1991). Protein-chemical standardization of the EGRAC test.
International Journal of Vitamin and Nutrition Research 61, 180-187