Are Free Vitamins the Best Way to Prevent Widespread Vitamin D Deficiency?
Over the weekend, reports came through about the rise of rickets in the UK over the past few years. The UK’s chief medical officer Professor Dame Sally Davies included recommendations to provide free vitamin supplements to all children under the age of five in her report “Our Children Deserve Better: Prevention Pays”. Her recommendations are based on surveys of vitamin D status in children that have shown a sizeable increase in rates of vitamin D deficiency and rickets, such as from groups led by Ahmed, Munns, Ward, and Gordon. Currently, vitamins are provided free of charge to low-income children.
The increase in vitamin D deficiency rates is thought to be due to reduced sunlight exposure. The UK food supply does not supply enough vitamin D to meet requirements (see report by Ashwell from the UK Food Standards Agency Workshop). While increasing sunlight exposure could help meet recommendations for some children, there are concerns that dark-skinned individuals may not be able to produce enough to avert deficiency (Farrar and associates).
Both free vitamin supplements and increasing sunlight exposure seem to be good ideas, however they rely on entire populations changing their behavior. Either people have to get out in the sun more, or take supplements. How realistic are these approaches? People don’t change behavior in the face of health-related recommendations for many reasons. One is related to a lack of information. Currently, research from Cleghorn found that around 20% of health visitors do not recommend vitamin D supplements to infants, and 45% do not recommend them to children aged up to five years in three regions in the UK. Compliance in taking supplements can also be low; some studies report compliance under 45% for vitamin D supplements (Siafarikas). It also appears that people at greatest risk of vitamin D deficiency may be less likely to know about vitamin D recommendations (Toher).
Valid reasons exist as to why people don’t get out in the sun more. Access to safe play areas outside for children may be limited. Some people cover up for religious reasons and will not be able to comply with recommendations to expose their skin. Others may be concerned about the long-term effects of sun exposure on their skin in terms of skin cancer, or be vigilant about sun-safe behavior due to sensitive skin.
Consider also the costs of treating vitamin D deficiency individually rather than at a population level. GP Online estimated that the cost of treating vitamin D deficiency was expected to exceed £100 million in the UK in 2013. This is due to the high costs of diagnosing deficiency and special-order products used to treat deficiency.
Fortification may be a better option. By increasing the vitamin D supply in staple foods, the population’s vitamin D status can be improved without requiring the individuals’ behavior to change. There is also a considerable cost benefit, especially in countries with public health care systems. Only minute quantities of vitamin D are needed to prevent deficiency: 15 micrograms are needed for an adult every day to fulfill vitamin D requirements. One gram of pure cholecalciferol (vitamin D3) therefore provides daily vitamin D for over 65,000 people in one day. Yet, the cost is low. When purchased in the bulk amounts needed for fortification, current prices are around $5 per gram depending on volume and formulation. The costs of fortifying a staple food with vitamin D for the UK population are less than £4 million.
Supplying the entire UK population with vitamin D in a staple food is extremely cost effective. It does not require individuals to change their behavior. If designed correctly, a fortification strategy can also target certain risk groups to ensure that those most at risk of rickets and vitamin D deficiency. Perhaps fortification should be considered in long term planning to prevent vitamin D deficiency-related diseases in the UK.
Lerner C (Ed). Annual Report of the Chief Medical Officer 2012, Our Children Deserve Better: Prevention Pays. https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/255237/2901304_CMO_complete_low_res_accessible.pdf
Ahmed SF, Franey C, McDevitt H, Somerville L, Butler S, Galloway P, Reynolds L, Shaikh MG, Wallace AM. Recent trends and clinical features of childhood vitamin D deficiency presenting to a children's hospital in Glasgow. Arch Dis Child. 2011 Jul;96(7):694-6. doi: 10.1136/adc.2009.173195. Epub 2010 Jun 28. http://www.ncbi.nlm.nih.gov/pubmed/20584848
Ashwell M, Stone EM, Stolte H, Cashman KD, Macdonald H, Lanham-New S, Hiom S, Webb A, Fraser D. UK Food Standards Agency Workshop Report: an investigation of the relative contributions of diet and sunlight to vitamin D status. Br J Nutr. 2010 Aug;104(4):603-11. doi: 10.1017/S0007114510002138. Epub 2010 Jun 4. http://www.ncbi.nlm.nih.gov/pubmed/20522274
Cleghorn S. Do health visitors advise mothers about vitamin supplementation for their infants in line with government recommendations to help prevent rickets? J Hum Nutr Diet. 2006 Jun;19(3):203-8. http://www.ncbi.nlm.nih.gov/pubmed/16756535
Farrar MD, Kift R, Felton SJ, Berry JL, Durkin MT, Allan D, Vail A, Webb AR, Rhodes LE. Recommended summer sunlight exposure amounts fail to produce sufficient vitamin D status in UK adults of South Asian origin. Am J Clin Nutr. 2011 Nov;94(5):1219-24. doi: 10.3945/ajcn.111.019976. Epub 2011 Sep 14. http://www.ncbi.nlm.nih.gov/pubmed/21918215
Gordon CM, Feldman HA, Sinclair L, Williams AL, Kleinman PK, Perez-Rossello J, Cox JE. Prevalence of vitamin D deficiency among healthy infants and toddlers. Arch Pediatr Adolesc Med. 2008 Jun;162(6):505-12. doi: 10.1001/archpedi.162.6.505. http://www.ncbi.nlm.nih.gov/pubmed/18524739
Munns CF, Simm PJ, Rodda CP, Garnett SP, Zacharin MR, Ward LM, Geddes J, Cherian S, Zurynski Y, Cowell CT; APSU Vitamin D Study Group. Incidence of vitamin D deficiency rickets among Australian children: an Australian Paediatric Surveillance Unit study. Med J Aust. 2012 Apr 16;196(7):466-8. http://www.ncbi.nlm.nih.gov/pubmed/22509879
Newmark HL, Heaney RP, Lachance PA. Should calcium and vitamin D be added to the current enrichment program for cereal-grain products? Am J Clin Nutr. 2004 Aug;80(2):264-70. http://www.ncbi.nlm.nih.gov/pubmed/15277144
Robinson S. Treating vitamin D deficiency to cost £100m a year by 2013. GP Online. 13 February 2012. http://www.gponline.com/News/article/1116651
Siafarikas A, Piazena H, Feister U, Bulsara MK, Meffert H, Hesse V. Randomised controlled trial analysing supplementation with 250 versus 500 units of vitamin D3, sun exposure and surrounding factors in breastfed infants. Arch Dis Child. 2011 Jan;96(1):91-5. doi: 10.1136/adc.2009.178301. Epub 2010 Sep 22. http://www.ncbi.nlm.nih.gov/pubmed/20861405
Toher C, Lindsay K, McKenna M, Kilbane M, Curran S, Harrington L, Uduma O, McAuliffe FM. Relationship between vitamin D knowledge and 25-hydroxyvitamin D levels amongst pregnant women. J Hum Nutr Diet. 2013 Aug 24. doi: 10.1111/jhn.12150. [Epub ahead of print] http://www.ncbi.nlm.nih.gov/pubmed/24033613
Ward LM, Gaboury I, Ladhani M, Zlotkin S. Vitamin D-deficiency rickets among children in Canada. CMAJ. 2007 Jul 17;177(2):161-6. Epub 2007 Jun 28. http://www.ncbi.nlm.nih.gov/pubmed/17600035