Iranian adults who consumed vitamin D-fortified bread saw improvements in vitamin D status and lipid profile that were similar to adults who consumed plain bread with a vitamin D supplement, according to recent study findings.
“Traditionally, dairy products (notably milk) are thought to be the best vehicles for vitamin D fortification,” Tirang R. Neyestani, PhD, of the Laboratory of Nutrition Research, National Nutrition and Food Technology Research Institute in Tehran, Iran, told Endocrine Today. “However, in many countries like Iran, milk consumption is meager in most age and sex subpopulations, making it actually ineffective for fortification purposes. Bread, on the other hand, is a staple food that could potentially be a good vehicle for many micronutrients, including vitamin D. Once fortified, it could be as good as a supplement pill or even better.”
Tirang R. Neyestani
In a randomized, double blind, placebo-controlled trial conducted in the fall and winter of 2015, Neyestani and Bahareh Nikooyeh, PhD, of the Laboratory of Nutrition Research, the National Nutrition and Food Technology Research Institute, and the faculty of nutrition sciences and food technology at Shahid Beheshti University of Medical Sciences in Tehran, and colleagues analyzed data from 90 healthy adults aged 20 to 60 years (49 men; mean age, 38 years) randomly assigned to one of three groups for 8 weeks. One group consumed 50 g bread fortified with 25 µg vitamin D3 plus placebo daily (n = 30); another consumed 50 g plain bread plus 25 µg vitamin D supplement daily (n = 30); a third group consumed 50 plain bread plus placebo daily (controls; n = 30). All participants completed 2-day food recalls. Researchers measured height and weight, estimated truncal and visceral fat and collected blood and urine samples at baseline and 8 weeks.
There were no between-group differences in serum 25-hydroxyvitamin D concentrations at baseline. However, at 8 weeks, the within-group changes of serum 25-(OH)D concentrations were 39 nmol/L (P < .001), 28.9 nmol/L (P < .001) and –9.2 nmol/L for the fortified bread, supplement-only and control groups, respectively (P = .001). Compared with baseline levels, serum intact parathyroid hormone levels fell approximately 13.5% in the fortified-bread group and 14.5% in the supplement-only group.
Researchers found time and group interactions for serum 25-(OH)D and BMI, waist circumference, visceral fat, serum LDL, HDL and intact parathyroid hormone. The fortified-bread group saw a decrease in visceral fat (–1.05%; P = .001), as did the supplement group (–0.96%; P = .006)
Changes in serum LDL concentration differed between groups, with the fortified-bread group experiencing a mean reduction of –10.4 mg/dL, whereas the supplement-only group saw an insignificant decrease of –6.6 mg/dL. Serum HDL increased in both vitamin D groups, with the fortified-bread group experiencing a greater increase (9.7 mg/dL vs. 5.7 mg/dL; P < .001).
“Improvement of vitamin D status of the community by the implementation of effective as well as sustainable, fortification programs may be a very cost-effective measure to lessen disease burden and [decrease] the related costs,” Neyestani said. “Efficacy studies, like this one, are short term in nature, so we do need longitudinal studies to keep track of the long-term consequences of such interventions and their possible effects on health aspects.” – by Regina Schaffer
For more information:
Tirang R. Neyestani,
PhD, can be reached at the Laboratory of Nutrition Research, National Nutrition and Food Technology Research Institute, P.O. Box 19395-4741, Tehran, Iran; email: email@example.com; firstname.lastname@example.org.
Disclosure: The researchers report no relevant financial disclosures.