B-Vitamins help maintain Healthy Bones
Until the last century, scientists weren’t certain that diseases such as scurvy, rickets and night blindness were caused by dietary deficiencies. The discovery of vitamins of vitamins in the early 1900s was founded upon controlled experimental studies manipulating the diet of humans and rats, chicks, pigeons, guinea pigs, mice and dogs.
Many people are still at risk of vitamin deficiency globally. Even more are at risk of vitamin inadequacy – vitamin concentrations in the body which are too low (insufficient) to support health. Bailey and colleagues examined the relationship between B-vitamin status and markers of bone health. Nationally representative data was obtained (NHANES, 1999-2004) from 2,806 women ≥50y. The cut-offs for low status were: vitamin B12 < 148 pmol/L, methylmalonic acid (MMA) >271 nmol/L, total homocysteine (tHCY) >13 nmol/L, serum folate <10 nmol/L, and red blood cell (RBC) folate <340 nmol/L.
Despite the spectacular success of mandatory folic acid fortification of enriched cereal grain products in the US beginning 1998, which helps maintain normal tHCY concentrations, elevated tHCY or MMA concentrations were associated with a greater risk of lumbar spine osteoporosis. The percentages of women with elevated tHCY and serum vitamin B12 were greater in women in the lowest (vs highest) quartiles of total-body and lumbar spine bone mineral density.
It is known that vitamin B12 status, in addition to folate status, affects tHCY concentrations. If the study had used only dietary B-vitamin intake, this interaction would probably not have been observed. Vitamin D is required to maintain healthy bones too. I wonder about the vitamin D status of these women.
This study in the Am J Clin Nutr confirms the value of measuring vitamin status in nutritional studies.
Bailey RL, Looker AC, Lu Z, Fan R, Eicher-Miller HA, Fakhouri TH, Gahche JJ, Weaver CM, Mills JL. B-vitamin status and bone mineral density and risk of lumbar osteoporosis in older females in the United States. 2015 Am J Clin Nutr doi: 10.3945/ajcn.115.108787
White Junod, S. Folic acid fortification: Fact and folly. FDLI Update Series on FDA History. Accessed July 30, 2015
Ouzzif Z, Oumghar K, Sbai K, Mounach A, Derouiche EM, Maghraoui AE. Relation of plasma total homocysteine, folate and vitamin B12 levels to bone mineral density in Moroccan healthy postmenopausal women. 2012 Rheumatol Int doi: 10.1007/s00296-010-1551-x
Jung S, Je Y, Giovannucci E, Willett WC, Rosner B, Ogino S, Cho E. Development of dietary methyl score using plasma homocysteine level in the large two US cohort study. 2013 FASEB J 27:622.10