Research

Scientists have shown increasing interest in a possible link between autism and low levels of Vitamin D. Dr Paul Whiteley sifts the evidence

Brighter life with sunshine vitamin?

Wider availability of low-cost supplements could help prevent health problems in millions of people at risk of vitamin D deficiency. So says NICE, the UKs National Institute for Health and Clinical Excellence.

It used to be thought that a lack of Vitamin D was linked only to the English disease of rickets, where its deficiency stops bones from being able to absorb enough calcium, with the result that they become deformed.

Now, however, Vitamin D has become the nutrient of the hour. It seems as if every day a new study is published telling us how an insufficiency or deficiency of Vitamin D is linked to all manner of health issues, both somatic (physical) and psychological/

form part of any restricted diet with autism in mind. Other case reports noted the coincidental diagnosis of rickets in children with autism.

Hypotheses then began to emerge to suggest that, alongside dietary factors that potentially impact on vitamin D levels in individuals with autism, more fundamental issues might be at work in linking a deficiency in the vitamin with autism. A paper from John Cannell3, founder of the Vitamin D Council, although speculative suggested that at least some of the incredible increase in the numbers of people being diagnosed with autism or autism spectrum disorder (ASD) may be reflective of increasing medical advice to avoid the sun, advice that has probably lowered vitamin

Light fantastic: ultra-violet rays from sunshine enable our bodies to create Vitamin D

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behavioural. The question for us is whether a lack of Vitamin D has any bearing on autism.

In fact, a possible connection for at least some people on the autism spectrum is emerging among the volumes of research being produced on the potential value of the so-called sunshine vitamin to health and wellbeing. As our understanding of the biological role of vitamin D has expanded, interesting data has been emerging on its relationship with autism.

Skin exposure to sunshine, or rather the ultra-violet (UV) rays of the sun, is an important part of the biology of vitamin D. Cholesterol (7-dehydrocholesterol) is the initial building block, which forms previtamin D via UV exposure on the skin. Body heat continues the

biological reaction to form vitamin D3 (cholecalciferol). The liver takes over to convert the vitamin D3 into 25-hydroxyvitamin D [25(OH)D] (calcidiol). Then the kidneys metabolise it into the metabolically active vitamin D hormone [1 ,25(OH)2D]1 so it can be used around the body.

How much exposure to sunshine we allow ourselves has become a problem of our modern age. Not only have decades of medical advice told us to avoid excessive exposure to the sun, but our increasing absorption with indoor activities such as watching television or playing on a computer has led to a reduction in time spent in the fresh air.

Nature also conspires to limit our sun exposure. In winter,

depending on where we live, we could potentially spend months without sunlight at the correct wavelength for the skin to be able to create vitamin D.

We are faced with the risk of millions of people not getting enough vitamin D. NICE has responded by following other

countries lead to promote greater access to supplements in the UK to counteract the trend towards an insufficiency or deficiency of the vitamin. In the US, The Vitamin D Council, a non-profit organization based in California, is adding to worldwide efforts to educate the public on vitamin D, sun exposure and health.

How theories developedOne of the earliest scientific reports on vitamin D deficiency being associated with autism2 implied that feeding issues and a poor diet might play a significant role. Feeding problems such as a restricted diet are nothing new when it comes to autism, and foods that are high in vitamin D, such as oily fish, are not normally noted to

Findings stress how a diagnosis

of autism may potentially place a person at greater risk of insufficiency or deficiency

Dr Paul Whiteley is

director of ESPA

Research, an

organization that

seeks to improve the

quality of life for

people with autism

spectrum conditions

through research

and the provision of

analytical services.

www.espa-research.

org.uk

D levels and would theoretically greatly lower activated vitamin D (calcitriol) levels in developing brains. Accepting that correlation and causation are not the same thing, such sentiments have sparked an increasing research interest in possible links between vitamin D and autism.

Sweden seems to be particularly taken by the idea that vitamin D deficiency might be linked to the condition. The countrys northerly location and its migrant population particularly from African countries have been integral factors in its research strategy in this area. Drawing on data suggesting that autism may be more common among Somali migrants than the Swedish average, for example, and acknowledging that climate and skin colour/tone can affect vitamin D levels, lower levels of vitamin D have been put forward as a risk factor for autism in this population.

Baby studyInvestigations have also focused on autism irrespective of ethnicity in related studies from Sweden. Fernell and colleagues4 reported on the analysis of vitamin D levels derived from newborn bloodspot cards. These cards carried samples from infants as part of national screening programmes to detect the presence of inborn errors of metabolism such as phenylketonuria (PKU). Such samples provide an important snapshot of a childs biological functioning when not affected by sun exposure patterns or eating habits.

Researchers concluded that those who subsequently went on to be diagnosed with autism presented with lower levels of vitamin D than their asymptomatic siblings. Such findings imply that low prenatal vitamin D may act as a risk factor for ASD, with the

controlled studies on this topic.As tempting as it might be to

immediately place everyone on the autism spectrum on a vitamin D supplement in the hope that symptoms may abate or quality of life improve, further investigations are required. There are those who think that vitamin D deficiency has nothing to do with the increase in autism cases; indeed, some authors have speculated that our increasing vitamin D consumption through the fortification of foodstuffs, for example, has had a detrimental effect7. Other research has also cast some doubt on whether maternal vitamin D status has any connection to offspring autism, or at least autistic traits.

While circulating levels of vitamin D have been the focus of most of the research so far, gaps still remain in our knowledge of vitamin D binding protein (used to transport vitamin D around the body) and vitamin D receptor, which allows the body to respond appropriately to the presence of vitamin D. Mutations in the gene controlling vitamin D receptor production have, for example, been reported in other conditions such as schizophrenia, although studies are lacking when it comes to autism.

Examination of vitamin D in relation to the autism spectrum is a growing area of research. Findings so far stress how a diagnosis of autism may potentially place a person at greater risk of insufficiency or deficiency. As for the rest of the population, issues with vitamin D availability when detected deserve to be corrected, given the seemingly wide-ranging effects reported following deficiency. Whether vitamin D supplementation could be seen as an intervention for autism remains to be empirically tested.

requirement for further research in this area.

Reports are emerging that suggest not only that a vitamin D supplement can help an individual with autism to avoid conditions such as rickets, but there may be other positive effects as well. Cannell5 first put forward a case for vitamin D supplementation potentially having a treatment effect in the core symptoms of autism.

Slowly, reports are emerging to suggest that at least in individual cases of vitamin D deficiency presenting alongside autism, taking a supplement of the nutrient may improve behavioural parameters, as reported by Jia and colleagues6. There remains, however, a dearth of larger, more

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Research

Sweden seems particularly

taken by the idea that vitamin D deficiency might be linked to autism

The nutrient of the hour: a diagram illustrating the chemical structure of one form of Vitamin D

References1 Grber U. et al. Vitamin D: Update 2013. From rickets prophylaxis to general preventive healthcare. Dermato-Endocrinology. 2013; 5:3, e2.2 Clark JH. et al. Symptomatic vitamin A and D deficiencies in an eight-year-old with autism. Journal of Parenteral & Enteral Nutrition 1993 May-Jun;17(3):284-6.3 Cannell JJ. Autism and vitamin D. Med Hypotheses. 2008;70(4):750-9.4 Fernell E. et al. Autism spectrum disorder and low vitamin D at birth: a sibling control study. Molecular Autism. 2015; 6: 3.5 Cannell JJ. Autism, will vitamin D treat core symptoms? Med Hypotheses. 2013 Aug;81(2):195-8.6 Jia F. et al. Core symptoms of autism improved after vitamin d supplementation. Pediatrics. 2015 Jan;135(1):e196-8.7 Bittker S. Infant Exposure to Excessive Vitamin D: A Risk Factor for Autism. Autism - Open Access. 2014; 4: 1.

Presented by:Mary Lynch Barbera, PhD, RN, BCBA-D (Author of: The Verbal Behavior Approach: How to Teach Children with Autism and Related Disorders)

Workshop Overview:Children with autism, regardless of age, ability level, or setting, need effective, individualised programming in order to reach their maximum potential.

Dr Barbera will give an overview of her book: The Verbal Behavior Approach: How to Teach Children with Autism and Related Disorders and will highlight several strategies that can be used immediately to begin to assess and teach children with autism.

Programming for early and intermediate learners of different ages will also be covered with systematic assessment and programming across the age range.

Who Should Attend:Professionals working with children with autism including: behavior analysts, speech and language therapists, educators, psychologists and therapists.

Parents of children with autism are also encouraged to attend.

For more information or to book online, visit: www.skyboundtherapies.co.uk

Understanding and Implementing Effective Autism Programming from Toddlers to Teens2 Day Workshop, 6th and 7th May 2015 Bristol, UK

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At Westgate College we continue to build upon the knowledge and skills that young people have gained through their school education. Students have access to a range of qualifications and support appropriate to meet individual needs. We offer vocational and non vocational programmes from 16 yrs onwards.

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The Royal School for Deaf Children Margate & Westgate CollegeVictoria Rd, Margate, Kent CT9 1NB. Telephone/Textphone: 01843 227561 SMS: 07797 800015 Fax: 01843 227637 School email: enquiries@royalschoolfordeaf.kent.sch.uk Website: www.townsendtrust.org

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