Less exposure to sunlight throughout the winter months or excessive use of sunscreens during the summer months, combined with relatively poor sources of vitamin D3 found in foods, may all contribute to an overall vitamin D deficiency. Some experts believe that up to 60% of Australian children and adults could be vitamin D deficient.

All about vitamin D

Vitamin D is commonly referred to as both a vitamin and hormone, produced by the body when your skin is exposed to sunlight. Small amounts of vitamin D can be found naturally in some foods including cod liver oil, cold water fish, egg yolk, milk, sprouted seeds and dark green leafy vegetables, although this is usually not enough to maintain good health. Vitamin D3 (cholecalciferol) is the bioactive form of vitamin D, identical to the vitamin D produced naturally by your body, whereas vitamin D2 (ergocalciferol) is a synthetic form of vitamin D. Vitamin D3 is more effective at raising vitamin D levels in the blood, making it the preferable choice of  in nutritional supplements. A daily dose of 1000IU of vitamin D3 can increase serum vitamin D levels by 25nmols/L over a 3 month period. Normal reference ranges for blood levels of vitamin D can vary between pathology laboratories, but it’s generally accepted that blood levels less than 50nmols/L indicate deficiency and blood levels between 52-72nmols/L indicate insufficiency.

Health benefits of vitamin D

Vitamin D receptors have been found throughout the body including the brain, blood vessel walls, pancreas, prostate and breast tissue, and the immune system. Alongside its well-known benefits for strong healthy bones, vitamin D is also important for:

• Enhancing your immune system response to bacterial and viral infections
• Affecting cell differentiation, proliferation and growth, helping to prevent abnormal cell changes
• Maintaining muscle strength
• Helping to reduce falls in the elderly - supplementation with 700-1000IU of vitamin D3 can reduce the number of falls in the elderly by 20%, reducing the risk of fractures
• Maintaining healthy blood vessel function
• Insulin secretion to help maintain healthy blood sugar levels
• Maintaining healthy brain function and mood
• Supporting women during preconception, pregnancy and breastfeeding

Risk factors for a vitamin D deficiency

• Age – the skins capacity to produce vitamin D is reduced in the elderly
• Limited or inadequate exposure to sunlight – excessive sunscreen usage, confined indoors
• Naturally dark skin colour – the pigment melanin in dark skin doesn’t absorb as much sunlight
• Certain medications – eg: glucocorticoids, powerful anti-inflammatories that deplete vitamin D levels
• Malabsorption syndromes – including Crohn’s and coeliac disease
• Lifestyle factors – air pollution, being overweight, alcohol intake
• Dietary deficiency
• Veiled women (particularly during pregnancy) and their infants
• Autoimmune health conditions – associated with vitamin D deficiency

The Australian government recognises the issue of vitamin D deficiency and currently vitamin D fortification is mandated for edible oil spreads and table margarine, and voluntarily for modified, powdered and skim milks, yoghurts and cheese.

Mr Vitamins recommends

Herbs of Gold Vitamin D3 1000

Vitamin D3 1000 in rice bran oil is a high strength vitamin D3 supplement Find out more and shop online for Herbs of Gold Vitamin D3 1000 here         References Bischoff-Ferrari, HA et al, 2009, ‘Fall prevention with supplemental and active forms of vitamin D: a meta-analysis of randomised controlled trials’, BMJ 2009; 339:b3692. Braun L & Cohen M (2015), Herbs & Natural Supplements – An evidence-based guide, vol. 2, 4^th edition, Chatswood, Elsevier. Higdon J (2003), An Evidence-Based Approach to Vitamins and Minerals, New York, Thieme. Pizzorno JE & Murray MT (2013), Textbook of Natural Medicine, 4th Edition, Missouri, Elsevier. Zimmermann M (2001), Burgerstein’s Handbook of Nutrition; Micronutrients in the Prevention and Therapy of Disease, 9th Edition, New York, Thieme.