ABSTRACT
People in India have a high prevalence of low vitamin B12 status and high plasma total homocysteine (tHcy) concentrations. In a proof of principle trial, we studied the effect of oral vitamin B12 (500 microg) and/or 100 g cooked green leafy vegetables (GLV) every alternate day in a 2x2 factorial design over a 6-week period. Forty-two non-pregnant vegetarian women (age 20-50 years) were randomly allocated to four study groups. Clinical measurements were made at the beginning and at the end of the study, and blood samples were collected before, and 2 and 6 weeks after commencement of intervention. Forty women completed the trial. Twenty-six women had low vitamin B12 status (<150 pmol/L) and 24 had hyperhomocysteinemia (>15 micromol/L). GLV supplementation did not alter plasma folate or tHcy. Vitamin B12 supplementation increased plasma vitamin B12 concentration (125 to 215 pmol/L, p <0.05) and reduced tHcy concentration (18.0 to 13.0 micromol/L, p <0.05) within first 2 weeks, both of which remained stable for the next 4 weeks. Plasma vitamin B12 and tHcy concentrations did not change in those who did not receive vitamin B12, and there was no change in plasma folate concentration in any of the groups. Blood haemoglobin concentration increased marginally within first two weeks in those women who received vitamin B12 (by 3 g/L, p <0.05) and the number of women with macrocytosis decreased from 2 to zero. There was no change in vibration sensory threshold during the period of the study. High-dose per oral vitamin B12 supplementation significantly reduced plasma tHcy within 2 weeks but did not achieve normal plasma tHcy concentration even after 6 weeks. People in India have a high prevalence of low vitamin B12 status and high plasma total homocysteine (tHcy) concentrations.
Subject(s)
Homocysteine/blood , Hyperhomocysteinemia/epidemiology , Vitamin B 12 Deficiency/epidemiology , Vitamin B 12/therapeutic use , Vitamin B Complex/therapeutic use , Administration, Oral , Adult , Dietary Supplements , Female , Folic Acid/blood , Homocysteine/drug effects , Humans , Hyperhomocysteinemia/drug therapy , India/epidemiology , Middle Aged , Prevalence , Treatment Outcome , Vegetables , Vitamin B 12/administration & dosage , Vitamin B 12 Deficiency/drug therapy , Vitamin B Complex/administration & dosageABSTRACT
BACKGROUND: Low vitamin B12 concentration in South Asian Indians is common, but the exact prevalence is not known. AIM: To investigate prevalence and associations of low vitamin B12 concentration and hyperhomocysteinemia in rural and urban Indian men living in and around Pune, Maharashtra. METHOD: We studied 441 middle-aged men (149 rural, 142 slum and 150 urban middle-class residents, mean age 39 y). Data on lifestyle, socio-economic status, nutrition and medical history were obtained. Circulating concentrations of vitamin B12, folate, ferritin, total homocysteine (tHcy), and haematological indices, and cardiovascular risk variables were measured. RESULTS: Median plasma B12 concentration was low (110 pmol/L): Overall, 67% of men had low vitamin B12 concentration (<150 pmol/L) and 58% had hyperhomocysteinemia (>15 micromol/L). Of the urban middle class, 81% had low vitamin B12 concentration and 79% had hyperhomocysteinemia. Low vitamin B12 concentration contributed 28% to the risk of hyperhomocysteinemia (population attributable risk) while low red cell folate contributed 2%. Vegetarians had 4.4 times (95% CI 2.1, 9.4) higher risk of low vitamin B12 concentrations and 3.0 times (95% CI 1.4, 6.5) higher risk of hyperhomocysteinemia compared to those who ate non-vegetarian foods frequently. Urban middle-class residence was an additional independent risk factor of hyperhomocysteinemia (odds ratio 7.6 (95% CI 2.5, 22.6), compared to rural men). Low vitamin B12 concentration was related to lower blood haemoglobin concentration and higher mean corpuscular volume, but macrocytic anemia was rare. CONCLUSION: Low vitamin B12 concentration and hyperhomocysteinemia are common in Indian men, particularly in vegetarians and urban middle class residents. Further studies are needed to confirm these findings in other parts of India.
Subject(s)
Hyperhomocysteinemia/epidemiology , Rural Population , Urban Population , Vitamin B 12 Deficiency/epidemiology , Adult , Diet, Vegetarian , Female , Humans , India/epidemiology , Male , Middle Aged , PrevalenceABSTRACT
The smallness of Indian babies is ascribed to small maternal size and their chronic under nutrition. Micronutrient nutrition of the mother may be particularly important. We investigated the relationship between maternal circulating concentrations of total homocysteine (tHcy), vitamin B12 and folate and offspring size at birth. Mothers of full term small for gestation age babies (SGA, gestation and sex specific birth weight <10th centile, N = 30) and mothers of appropriate for gestational age babies (AGA, >10th centile, N = 50) were compared for their body size, plasma tHcy, vitamin B12 and red cell folate concentration at 28 week gestation. Mothers of SGA babies were lighter and shorter than those of AGA babies (P <0.05, both) and had higher plasma tHcy concentration (P<0.01). Total homocysteine concentrations were inversely related to plasma vitamin B12 and red cell folate concentrations (r = approximately -0.5, P <0.01, both). Seventy percent of the women had a low vitamin B12 status (plasma vitamin B12 <150 pmol/L) but none were folate deficient (red cell folate <283 nmol/L). Higher maternal plasma tHcy concentration was significantly associated with lower offspring birth weight (r = -0.28, P<0.05 adjusting for maternal height, weight, gestation at delivery and the baby's gender), this effect was reduced by adjustment for red cell folate concentration. We conclude that maternal vitamin B12 deficiency reflected in plasma tHcy concentration contributes to small size of Indian babies.
