when we talk about sun exposure, there
are discussions on balancing the need to protect ourselves against the harmful
UV radiation from the sun against the need for adequate levels of vitamin D.
it’s estimated that 1 billion
are either deficient or not reaching sufficient levels of vitamin D. That being
said, in Australia, we are lucky to enjoy more sunshine during the year than
many other countries. We also know that some people are more at risk of being
deficient than others.
with any health topic, one of the best things that you can do is be fully
informed of the risks and benefits so that you can take the best course of
action for you and your family.
that in mind, here’s everything you need to know about vitamin D.
D is an important vitamin for general good health and wellbeing. One of its most important
functions is to help the small intestine to absorb calcium
from the diet. For this reason, vitamin D is especially important for
maintaining healthy bones and teeth. It can help to prevent and treat
conditions caused by inadequate bone formation and mineralization like rickets
D also helps to support good immune health, possibly playing a role in
protecting against some autoimmune diseases, such as multiple
sclerosis, type 1 diabetes and cancer. There is also evidence
that it may help to prevent and treat cardiovascular
disease, the flu, and
symptoms of depression, though
further research is needed.
D also helps to stimulate insulin
secretion, helping to maintain glucose tolerance. Some
studies have even suggested that it could help with weight
based on a reduction in appetite associated with calcium intake.
What is it
Vitamin D has two main forms: the
first is vitamin D2, known as ergocalciferol, which is found in plants and yeast and
is commonly added to foods like margarine and bread.
The second is vitamin D3, which is
also added to foods and found in fatty fish and eggs. Vitamin D3 is also known
as the ‘sunshine vitamin’, as 80-90% of the body’s stores are from exposure to the sun.
How much do
Vitamin D levels in the body are
typically measured by nanomoles per litre, or nmol/L. According to the Australian Government Department of Health, Australian organisations typically consider
levels lower than 50 nmol/L as suboptimal.
The Australian Health Survey 2011-12 found that 23% of Australians had vitamin D
levels lower than 50 nmol/L.
The recommended daily adequate intake of vitamin D is Australia is:
micrograms (200 IU) for children, adolescents and adults aged 19-50 years,
micrograms (400 IU) for adults aged 51-70 years, and
micrograms (600 IU) for adults over 70.
However, it should be noted that
these recommendations are based on no or minimal sunlight.
When it comes to how much time we
need in the sun, this can vary between location, skin type, and season. Osteoporosis Australia recommends a few minutes on most days during
summer (preferably early or late in the day) for all states and year-round for
northern cities like Brisbane or Darwin. During the cooler months, 2-3 hours
per week is recommended.
the risks of deficiency?
A severe vitamin D deficiency can lead to bone health issues, including conditions such as
rickets or osteomalacia.
Other problems associated with not getting enough vitamin D are osteoporosis, fractures, cardiovascular disease, respiratory conditions, gastrointestinal
problems, musculoskeletal conditions, and more.
There are some people who have a
greater risk of health conditions resulting from a vitamin D deficiency. Older
people, for example, are particularly vulnerable. This is because falls are a
major health problem, and a vitamin D deficiency is associated with muscle
weakness and a higher rate of falls. In fact, interventional studies have found that daily dosing of vitamin D was
associated with a 20-30% reduction in fall rates.
Pregnant women are another group
who are at risk. Low concentration of vitamin D is associated with the development of gestational diabetes. Vitamin D deficiencies are also related to a higher risk of complications including preeclampsia, cesarean section
rate, low birth weight, and impaired skeletal, lung and immune development.
How do I
know if I’m deficient?
Most Australians get a sufficient
level of vitamin D during the summer. However, the prevalence of vitamin D
levels lower than 50 nmol/L has shown to be higher in winter as there is less sunshine. This is especially the case for those living in the south-eastern states of Australia,
including Victoria, the ACT and Tasmania.
Other people who are more likely to be deficient are:
darker skin who require more UV exposure to produce vitamin D
spend a lot of time indoors, such as people in nursing homes
taking particular medications
take a supplement?
Whether or not you need to take a
vitamin D supplement depends on a range of factors, and the answer will vary
from person to person.
If you’re confused or need extra
guidance, speak to your GP or visit your local Capital Chemist pharmacist for
more information and advice.