Vitamin D supplementation: Recommendations for Canadian mothers and infants

Question 1

How many cases of confirmed rickets occurred between 2002 and 2004 in Canada?

Answer 1

104

Question 2

What percentage of patients with confirmed rickets were First Nations?

Answer 2

13%

Question 3

What percentage of patients with confirmed rickets were Inuit?

Answer 3

12%

Question 4

What percentage of patients with confirmed rickets were Middle Eastern?

Answer 4

14%

Question 5

What has vitamin D deficiency been associated with?

Answer 5

1. Osteoporosis
2. Asthma
3. Autoimmune disorders i.e. RA, MS, IBD
4. Diabetes
5. Muscle function disturbance
6. TB resistance
7. Cancers

Question 6

What has maternal vitamin D deficiency been associated with?

Answer 6

1. Bone density
2. Asthma severity
3. Susceptibility to type 1 DM
4. Enamel defects in primary and permanent teeth –> dental caries
5. Newborn hypocalcemia
6. Newborn rickets
7. SGA
8. Decreased vitamin D in breast milk

Question 7

What is the origin of vitamin D3?

Answer 7

Produced in skin of animals

Question 8

What is the origin of vitamin D2?

Answer 8

Plants

Question 9

What is 25-OH-vitamin D?

Answer 9

Stable but inactive form
Defines vitamin D status
25-hydroxylation in liver

Question 10

What is 1,25 (OH)-2vitamin D?

Answer 10

Unstable but active form

1-hydroxylation in kidney

Question 11

What is optimal plasma 25(OH)-vitamin D levels?

Answer 11

PTH production and calcium re-absorption from bone minimized
Intestinal calcium absorption stabilized

75-225 nmol/L

Question 12

What level of vitamin D is considered pharmacological with potential adverse effects

Answer 12

> 225nmol/L

Hypercalcemia, calcium deposits in tissue

Question 13

What level of vitamin D is considered toxic?

Answer 13

> 500nmol/L

Question 14

What level of vitamin D is considered deficient?

Answer 14

<25nmol/L

Question 15

What level of vitamin D is considered insufficient?

Answer 15

25-75nmol/L

Question 16

What factors affect sun exposure and thus vitamin D3 production?

Answer 16

1. Latitude
2. Skin pigmentation
3. Clothing
4. Sunscreen

Question 17

What is the Canadian Dermatology Association recommendation regarding sun exposure?

Answer 17

<1yo avoid direct sunlight and use sunscreens

Question 18

What are some food sources for vitamin D?

Answer 18

1. Infant formulas, dairy milk, fortified rice and soy beverage ~400IU/L
2. Canned salmon (530IU/3oz)
3. Canned tuna (200IU/3oz)
4. Fatty fish
5. Aquatic mammals i.e. seals, polar bears

Question 19

What is the Health Canada recommendation for maternal supplementation?

Answer 19

200IU/day

Question 20

How much vitamin D is in prenatal supplements?

Answer 20

400IU vitamin D3 per day

Question 21

What is the recommendations regarding vitamin D supplementation in preterm infants?

Answer 21

200IU/kg/day to maximum 400IU/day

Question 22

What is the recommendations regarding vitamin D supplementation in term infants?

Answer 22

400IU/day from any source x 1 year

800IU/day for northern Native communities during winter months

Question 23

What is the recommendations regarding vitamin D supplementation in 1-8yo children?

Answer 23

200IU/day

Question 24

What is the recommendations regarding vitamin D supplementation in 19-50yo?

Answer 24

200IU/day

Question 25

What is the recommendations regarding vitamin D supplementation in 51-70yo?

Answer 25

400IU/day

Question 26

What is the recommendations regarding vitamin D supplementation in >71yo?

Answer 26

600IU/day

Question 27

What vitamin D dosing might be needed in adults?

Answer 27

800-1000 IU/day up to 2000-4000IU.day in special circumstances

Question 28

What is the highest continuing daily intake of vitamin D that is likely to pose no risks of adverse health effects for infants up to 1yo?

Answer 28

1000 IU/day

Question 29

What is the tolerable upper intake level of vitamin D in adults?

Answer 29

2000IU/day

Evidence absence of toxicity 10 000IU/day vitamin D3

Question 30

What is the prediction regarding supplementation with vitamin D3?

Answer 30

As more and more evidence of the relationship between the level of vitamin D in diseases such as osteoporosis, cancer, diabetes, autoimmune diseases and neuromuscular disorders emerges, it is predicted that treatment with physiological doses of vitamin D3 (between 4000 IU/day to 10,000 IU/day from all sources, including sun, food and supplements) with periodic monitoring of blood 25(OH)D (calcidiol) levels and calcium levels will become routine to maintain 25(OH)D levels of 75 to 150 nmol/L

Question 31

In which groups of people is vitamin D deficiency most common?

Answer 31

Common in adults and children in Canada esp.:

1. Aboriginal
2. high Arctic regions
3. Infants <1yo esp. if breastfed

Question 32

What vitamin D supplementation level is required in pregnancy and lactation to maintain optimal levels of 25(OH)D for both mothers and their infants?

Answer 32

> 1000IU/day

Question 33

What does vitamin D requirements vary with?

Answer 33

Weight and BMI

Question 34

Why are vitamin D levels lower in high Arctic regions?

Answer 34

1. Lack of light for much of the year
2. Dressing for intense cold decreases the opportunity for vitamin D production in skin
3. Dependence of traditional vitamin D rich foods has diminished

Question 35

What are some other recommendations regarding vitamin D supplementation?

Answer 35

1. In infants and children living in the north, levels of supplementation of vitamin D of 400 IU/day to 800 IU/day appear safe. However, vitamin D deficiency continues to be prevalent in this group and doses may need to be increased, especially in light of the evidence that the amount of vitamin D needed for sufficiency can vary with weight or BMI. Overweight and obese children are at higher risk for vitamin D deficiency and may need a higher intake
2. There appears to be discrepancy between our current practice and recommended intakes, which needs to be addressed

Question 36

What are the CPS recommendations regarding vitamin D supplementation?

Answer 36

1. Focus special attention on First Nations and Inuit peoples, due to high level of vitamin D deficiency and insufficiency
2. Recommendations for vitamin D intake from all sources:
   a) Preterm infants 200IU/kg/day (max. 400IU/day)
   b) Term infants <1yo: 400IU/day
   c) Term infants <1yo north 55th parallel: 800IU/day
   between October and April
   d) Term infants <1yo between 40-55th parallel with additional risk factors: 800IU/day
3. Research is required for optimal dosing in older infants as may need to be weight based
4. Infants and children should be exposed to sunlight for short periods (<15min/day) to maximize cutaneous production of vitamin D yet minimize skin damage
5. Consider supplementing pregnant and lactating women (esp. in winter) with 2000IU/day vitamin D
6. Check vitamin 25(OH)D and calcium periodically on 2000IU/day regimen
7. Research recommended for:
   a) Effectiveness and possible side effects of supplementation of mothers during pregnancy
   b) Vitamin D requirements for toddlers and older children
   c) Development of a cheaper, accurate, and more universally available assessment of vitamin D status than the 25(OH)D assay
   d) Indicators of hypercalcemia should be included in any investigations