No abstract

No abstract

No abstract

Six sedentary to moderately active men with biochemical signs of riboflavin deficiency were studied under metabolic ward conditions to examine the effects of physical activity on riboflavin status. All participants were subjected to additional exercise (EXER) for an 18 d period between two maintenance (M1 and M2) periods (16 and 13 d respectively) of habitual physical activity. Energy balance and riboflavin intake were maintained throughout the study. Riboflavin status, as judged by a significant reduction in erythrocyte glutathione reductase (EC 1.6.4.2) activation coefficient (EGR-AC), improved on changing from home (1.53 (SD 0.14)) to period M1 (1.36 (SD 0.21)) diets. The exercise period, however, resulted in a significant deterioration in riboflavin status (1.57 (SD 0.31)) which persisted in the subsequent period M2 (154 (SD 0.15)). There was a concomitant fall in the urinary excretion of riboflavin only in the EXER period, when results were expressed as a percentage of the dietary intake of riboflavin. These results suggest an increased demand for the vitamin for selective biochemical functions during exercise. However, the energy cost of walking (treadmill 4 km/h), 50 W and 100 W work-loads (bicycle ergometer) as well as delta mechanical efficiency (DME) did not change during the three metabolic periods. The urinary excretion of riboflavin was inversely related to DME (P -0.49; P < 0.05) and directly correlated with haemoglobin levels (u 0.63; P < 0.005). The present study suggests that riboflavin status further deteriorates during a short period of increased physical activity in individuals whose riboflavin status is marginal.Riboflavin : Glutathione reductase: Physical activity: Mechanical efficiency . ___Studies confined to clinical cases of malnutrition fail to assess the situation in its entirety since they only address the proverbial tip of the iceberg. Investigations on subclinical or biochemical malnutrition, which are major problems in India, are important to rule out any functional consequences on the health and productivity of the population. In India riboflavin deficiency is very common (National Nutrition Monitoring Bureau, 1980), being possibly modulated by dietary as well as non-dietary factors (infection, physical activity etc.; Belko e t Bamji et al. 1987). The basis of the present study was the observed seasonal variations in the riboflavin status of rural Indian women, as assessed by erythrocyte glutathione reductase (NADPH glutathione oxidoreductase; EC 1 . 6 . 4 . 2 ; EGR) activation coefficients (EGR-AC) (National Institute of Nutrition, 1988). Although a majority of women had marked biochemical riboflavin deficiency throughout the year, there was a significant deterioration in riboflavin status during the monsoon season compared with the summer or winter seasons. This change could not be attributed to changes in diet or morbidity. Since during the rains there was augmented physical activity * Present address:

No abstract

No abstract

Effects of low estrogen combination type oral contraceptives on some of the biochemical parameters used for assessing vitamin nutritional status were investigated in a group of women who had used the pill for 6 to 12 months. Another group of women was examined initially and then at one or more points of time within the first 6 months of treatment. Following changes were observed in women treated with oral contraceptives: 1) increased excretion of kynurenic acid and xanthurenic acid following tryptophan load; 2) increased EGOT activity and also an increase in vitro stimulation of EGOT with added PALP; 3) increased plasma vitamin A levels; 4) fall in erythrocyte folate levels; 5) fall in erythrocyte transketolase activity with no change in vitro stimulation with TPP; and 6) fall in erythrocyte riboflavin concentration associated with a decrease in erythrocyte glutathione reductase activity and increase in vitro stimulation with FAD. Most of these changes were observed during the first few cycles of oral contraceptive treatment.

I . A study amongst schoolboys in villages around Hyderabad, India, showed that almost all the boys had riboflavin deficiency, 61 % had pyridoxine deficiency, and 9'4% had thiamin deficiency as judged by enzymic tests.2. The prevalence of angular stomatitis was 41.3 yo and that of glossitis was 18.2 %. Biochemical deficiency of riboflavin and pyridoxine was marginally higher in children with angular stomatitis with or without associated glossitis, than in children without oral lesions.3. Treatment with B-complex vitamins (containing 4 mg riboflavin and 10 mg pyridoxine) daily for I month produced significant reduction in the prevalence of glossitis but had no effect on angular stomatitis. The latter responded to topical application of gentian violet. 4.Small but significant changes in erythrocyte enzymes occurred over the period of I month even without vitamin supplements.5 . Results suggest that while glossitis is a relatively early manifestation of riboflavin or pyridoxine deficiency or both, angular stomatitis has a more complex aetiology perhaps associated with infection.Lesions of the mouth such as angular stomatitis and glossitis have been shown in experimentally-induced riboflavin deficiency as well as pyridoxine deficiency. Recent reports from the National Institute of Nutrition, Hyderabad, show that in adults this condition responds to treatment with either riboflavin or pyridoxine (Krishnaswamy, 1971 ; Iyengar, 1973). While glossitis seems to be more common amongst the adults of our community, angular stomatitis is more common amongst the children.A recent survey of rural schoolchildren living near Hyderabad, revealed a higher incidence of angular stomatitis amongst boys than amongst girls. The condition failed to respond to treatment with either riboflavin alone or with B-complex vitamins over a period of 3 weeks and 4 weeks respectively (K. V. R. Sarma, M. Damodaran and A. Tiar, unpublished results).The present study was carried out to investigate this observation further, by applying biochemical tests for assessing vitamin status, and examining the response to topical application of gentian violet. EXPERIMENTALThe subjects, 407 boys aged 5-1 3 years old and attending four rural schools near Hyderabad, were examined for clinical signs of vitamin deficiency such as angular stomatitis, glossitis, cheilosis, Bitot's spots, phrynoderma and angular scars. Of these, 168 boys had active angular stomatitis with or without glossitis (group A) whereas 134 boys were completely free of all lesions of the mouth including healed scars (group B). Boys in group A were further divided randomly into three subgroups (groups AI, A2 and A3) and those in group B into two subgroups (groups BI and B2).These boys were treated daily with either two tablets of B-complex vitamins (containing (mg/tablet): thiamin 2, riboflavin 2, pyridoxine 5, calcium pantothenate 2, niacin 20) (groups Ar and BI) or with placebo tablet containing IOO mg lactose (groups A2 and B2) or by topical application of a solution of gentian violet (10 g/l...