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Fortification with Vitamin D. Edward Giovannucci, MD, ScD. Sunlight (UV-B). Diet. Vitamin D. Liver. 25(OH) Vitamin D. Other cells 1 -OHase. [ Ca ++] PTH . Kidney 1 -OHase. 1,25(OH) 2 D. 1,25(OH) 2 D. Calcium Phosphorus Homeostasis (Endocrine). Other Functions
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Fortification with Vitamin D Edward Giovannucci, MD, ScD
Sunlight (UV-B) Diet Vitamin D Liver 25(OH) Vitamin D Other cells 1-OHase [Ca ++] PTH Kidney 1-OHase 1,25(OH)2D 1,25(OH)2D Calcium Phosphorus Homeostasis (Endocrine) Other Functions (Paracrine, Autocrine)
Evidence Compelling: Evidence Strong: • Rickets • Osteomalacia • Osteoporosis / fractures • Muscle weakness / falls • Some cancers • Multiple sclerosis • Other autoimmune diseases • Some infections / TB Some Suggestive Evidence: • CVD • Asthma • Congestive heart failure • Periodontitis • High Blood pressure • Type 2 diabetes mellitus Diseases Potentially Related to Vitamin D Deficiency:
How Much Vitamin D is Required For Optimal Health? • 25(OH) vitamin D is best indicator • Bone health is currently clearest endpoint • Examine intakes required to achieve • a specific 25(OH)D level
Criteria for Bone Health • Suppressing maximally PTH • Bone mineral density • Calcium absorption • Rate of bone loss • Fracture risk • Risk of falling
Vitamin D and PTH Holick MF et al., J Clin Endocrinol Metab 2005
Serum Ca AUC and Related Variables Heaney RP et al., J Am Coll Nutr 2003
Time course of the mean increment in serum total calcium in two studies. In one, vitamin D status was elevated (D+), and in the other, it was not (D–). Heaney RP et al., J Am Coll Nutr 2003
Forest Plots Comparing the Risk of Falling between Vitamin D-Treated Groups and Control Groups for the Primary Analysis Bischoff-Ferrari, H. A. et al. JAMA 2004
Hip and Nonvertebral Fracture Efficacies by Achieved 25-Hydroxyvitamin D Levels in 400 IU/d and 700-800 IU/d Vitamin D-Treated Groups Bischoff-Ferrari, H. A. et al. JAMA 2005
Garland 1989 Braun Tangrea 1996 Feskanich 2004 Wactawski-Wende 2006 Pooled odds ratio = 0.49 < 0.0001 p 0.1 1.0 10.0 Odds ratio (highest vs. lowest quintile) and 95% confidence interval Colorectal Cancer: Serum 25(OH)D Studies Garland C. et al., 2006
NHS, HPFS Combined Cases Season of Blood Draw Summer Multivariable RR P trend = 0.26 Winter P trend <0.001 Season-Specific 25(OH) Vitamin D Quartile Wu, K., Submitted.
Vitamin D Oral Intake Associated with 50% Reduction in Risk of Colorectal Cancer Observation Studies, 1985-2005 Gorham ED et al., J Steroid Biochem Mol Biol 2005
g/cm2 0.04 BMD (g/cm2) 0.02 Fracture (RR) RR 0 Colon Cancer (RR) sec or mm 8’ Walk (sec) Attachment Loss (mm) Median 25-OHD
Risk Factors for Hypovitaminosis D • Living in the North • Dark skin pigmentation • Old age • Obesity • Avoidance of sun • Low intake • Various medical conditions • Clothing practices
Photosynthesis of precholecalciferol (previtamin D3) at various times on cloudless days in Boston in October () and July (). Holick MF. Am J Clin Nutr 1994
Effect of month of year on mean 25(OH)D levels (upper panel), and the percentage prevalence of vitamin D insufficiency. Vieth R et al., Eur J Clin Nutr 2001
Approaches To Increase Vitamin D • Increase sunlight exposure • Increase natural food sources • Supplementation • Fortification
Sun Exposure Recommendations Need to Account For: • region • season • time of day • % exposed skin • length of exposure • skin pigmentation • prevention of sun burn • prevention of skin cancer • use of sun screen
Adult Dietary Reference Intake (U.S.) Ages 19–50 y 200 IU / day 51–70 y 400 IU / day 70 y 600 IU / day
Time Course of Serum 25(OH)D Concentration for 4 Dosage Groups The points represent the mean values, and error bars are 1 SEM. The curves are the plot of Equation 1, fitted to the mean 25(OH)D3 values for each dosage group. The curves, from the lowest upward, are for 0, 25, 125, and 250 µg cholecalciferol (labeled dose)/d. The horizontal dashed line reflects zero change from baseline. Heaney RP et al., Am J Clin Nutr 2003
Regression of the Equilibrium Increment () in Serum 25(OH)D3 Concentration for the Means of Each Treatment Group Heaney RP et al., Am J Clin Nutr 2003
Approaches To Increase Vitamin D • Increase sunlight exposure • Increase natural food sources • Supplementation • Fortification
Supplementation • Most supplements have 400 IU • Many supplements have D2 instead of D3 • Manufacturers hesitate to vitamin D • because T.U.L. is 2000 IU/day
Serum 25(OH)D concentration (nmol/L) by intake category for African American (dark bars) and white (gray bars) women. Intake categories: none = reference (lowest response in any reference category); milk = >3 servings/wk; cereal = >3 servings of fortified cereal/wk; supple. = daily intake of supplement containing 400 IU/d Calvo MS & Whiting SJ, J Nutr, 2006
Vitamin D has been approved by the FDA in recent years as a nutrient supplement in calcium fortified fruit juice and fruit juice drinks under 21 CFR Part 172.380, and these are also now being used for calcium and Vitamin D nutrient enrichment to increase intake in the U.S. population. We applaud such increased diversity of food enrichment. However, we strongly suggest that cereal grain products be added to the list, as a group of very reliable nutrient carriers, little prone to permit excess intake, safe and simple to use, low cost, very broadly consumed and well distributed in the general population. This group of foods is widely consumed across wide variations of ethnic, cultural and age differences in the U.S. Docket #2006P-0205/CP1 May 12, 2006
Our choice of cereal grain products for enrichment as a vehicle to increase calcium intake in the U.S. is guided by the following: 1. Approximately one fourth of the daily calorie intake in the U.S. is from cereal grain products, and the intake of total cereal grain products does not vary greatly by income or geographic region in the U.S. 2. Cereal grain product enrichment has been historically credited for (essentially) the eradication of pellagra by niacin enrichment in the U.S. . . . More recently, addition of folic acid (I.e. folate) to cereal grain enrichment has significantly reduced neural tube defects in newborns in the U.S. Docket #2006P-0205/CP1 May 12, 2006
Selected Parts of the U.S. Code of Federal Regulations (2001), Title 21, Sections 136, 137, and 139, That Relate to Calcium and Vitamin D
Estimated Increased Daily Intake of Vitamin D from Major Cereal Grain Product Foods, If Current Optional Enrichment Regulation Became Mandatory (USDA Data, 1997) USDA, Economic Research Service, Food Consumption Data System 2005
The Nutrition Facts panel from a new type of dietary supplement showing the highest vitamin D content of a dietary supplement to date. Calvo MS & Whiting SJ, J Nutr, 2006
Fortification: Practical Issues • Cost • Stability • Objections by • vegetarians (D3) • Toxicity
Risk of Kidney Stones: Treatment Placebo 449 381 18,176 18,106 RR = 1.17 (CI, 1.02-1.34) Women’s Health Initiative Trial 400 IU Vitamin D + 1000 mg Calcium