Vitamin D, the sunshine vitamin!
What our body
needs…
What our
body needs…
…can be
found in food. Every food contains a range of nutrients. When consumed in the
right quantities, all our body’s physical and mental functions can work as
intended. This creates fertile ground for performance, growth and development,
and helps preserve our health. Nutrients are vital.
Inadequate consumption will cause deficiencies!
Nutrient
deficiency
How to
recognise deficiencies
If your body
does not get the nutrients it needs, you will develop a nutrient deficiency.
The symptoms vary widely depending on the nutrient in question.
Vitamin D: a
hot topic
You’ve
probably heard of vitamin D before. This vitamin really is in the foreground
lately. Especially in winter time, you’ll come across lots of articles in
magazines and on the Internet exploring the topic. But what’s actually the
truth? Who is more likely to develop a deficiency? Is it even possible to get
enough vitamin D? Or do we need to supplement with synthetic alternatives?
We have all
the answers for you in this session!
The role of
vitamin D
There’s more than one actualy!
When we
speak of vitamin D, we imply its various forms – the so-called calciferols. The
most important are vitamin D2 (ergocalficerol) and D3 (cholecalciferol). Good
to know: vitamin D is fat-soluble! This allows us to stock up on it, for
example in our fatty tissue, and to fall back on it in ‘hard’ times. It also
means you can overdose if you take in too much synthetic vitamin D, though.
Vitamin D is
fat-soluble
Vitamin D
for strong bones!
Vitamin D is
essential for bone health. It plays a major role in bone mineralisation: for
example, it promotes the absorption of calcium and phosphate from food in the
body and helps build these into our bones. This makes your bones stronger.
Alongside this main function, vitamin D supports muscle development and the
immune system.
What is your
daily vitamin D requirement?
For all the
processes that require vitamin D to run smoothly, you’ll need different amounts
depending on your age:
–
under 1
year: 10 micrograms
–
1-60 years:
20 micrograms
–
over 60
years: 20 micrograms
Occurrence and
formation
The sunshine
vitamin
Vitamin D is
a special vitamin because our body is able to produce it itself when certain
conditions are met. But only when sunlight touches the skin. The vitamin D 3
that is formed there gets converted into calcifediol in the liver and then
further into calcitriol in the kidneys. Calcitriol is the biologically active
form, i.e. the effective form of vitamin D.
The majority
(80-90 %) of this vitamin is made in our body. It is difficult to estimate how
long you need to spend in the sun for a good dose. The duration can vary a lot.
It depends, for example, on the time of year and day, the latitude, your skin
type, or your clothing. For example, 10 minutes in the afternoon sun in the
summer can be enough when the sun shines straight on your arms and face.
But light
alone is not enough
Sunshine
that we enjoy through windows is sadly not enough for vitamin D to synthesise.
That’s because it needs UV-B rays and these do not make it through the glass.
We should therefore be spending time outside in the fresh air.
Which foods
contain vitamin D?
We only
cover 10-20 % of our vitamin D needs through food – only a small part. It is
primarily found in animal derived foods, especially fish. As it is fat-soluble,
fatty fish such as salmon, eel, herring, and mackerel are particularly rich in
vitamin D. Egg yolk and margarine and some edible mushrooms such as champignons
also contain the vitamin.
What should
we do in winter?
Since most
of the vitamin D is produced when our skin is exposed to sunlight, winter is a
real issue due to the days being shorter, the sun not shining for as long or as
strongly, and it also being cold and us covering ourselves up with thick
clothing. Fortunately, vitamin D is fat-soluble and can be stored in our fatty
tissue, for example. That way we can build our stocks in the summer.
Deficiency &
high-risk groups
Vitamin D
deficiency
Vitamin D
deficiency occurs when vitamin D absorption through food, the body’s own
production through the skin, or the vitamin D metabolism is impaired over a
long period of time. Note, however, that vitamin D levels in the blood may
fluctuate seasonally. A lower level does not necessarily mean that you will
experience symptoms.
Only a
doctor can diagnose a deficiency!
A vitamin D
deficiency is something you should take seriously. If there is a shortfall, for
example in babies and children, there aren’t enough minerals to build the
bones. The bones stay soft and can deform, which leads to rickets. In adults,
bones are deprived of minerals, they soften and break more easily! A vitamin D
deficiency increases the risk of osteoporosis in old age.
It can also
impair muscle strength and heighten proneness to infections.
Who’s at
risk?
Vitamin D
deficiency is most likely to occur in people who do not spend enough time out
in the sun. This includes people who only step outside with their skin fully
covered. People with darker skin are more at risk because
they can make less vitamin D (or more slowly) due to a higher proportion of the
pigment melanin in the skin. Since the ability to produce vitamin D
decreases significantly with age, older people tend to develop a deficiency
much more frequently than younger people. But the youngest are also at risk:
babies get only little vitamin D through their mother’s milk and should not be
exposed to direct sunlight.
Certain
conditions pose a risk
Some
diseases may increase the risk of vitamin D deficiency. These include chronic
gastrointestinal conditions, or liver and kidney disorders. Some medicines also
interfere with the vitamin D metabolism.
Tanning studio?
Nonsense!
Will going
to the tanning studio help prevent a deficiency? This is definitely not to be
recommended – especially not for children and young people. They increase the
risk of skin cancer and are therefore not to be recommended!
Should we
take a vitamin D supplement?
Some foods
are fortified with vitamin D. But these are not absolutely essential since the
focus should always be on the body’s own vitamin D production. Moreover, food
supplements are only advisable if a doctor has diagnosed a deficiency. You
should be careful not to ‘over supplement’ because too much of fat-soluble
vitamins can also cause problems. Infants are an exception here, for whom
correctly dosed supplements can be prescribed by the doctor.
Overdose can
cause kidney calcification! An oversupply is when vitamin D supplements are
taken in excess.
Good vitamin
D intake
It is worth
watching your vitamin intake. In older age, if this is ensured, bones do not
break as easily and muscle strength, balance and brain function are also more
protected. The evidence speaks for itself. Whether vitamin D also reduces the
risk of certain types of cancer, cardiovascular diseases, and type II diabetes
still needs to be studied further.
What you can
do:
You should
spend plenty of time outdoors – even in winter. Oily fish should definitely be
on the menu once or twice a week. These include herring, eel, mackerel or
salmon. If you are lucky enough to enjoy some sunshine, vitamin D supplements
are not necessary. For those at a high risk such as infants, pregnant and
breastfeeding women, or the elderly, supplements can be beneficial – but only
if a doctor prescribes the correct dosage.
One final
tip: vitamin D is fat-soluble. As such, it is much more easily absorbed if you
consume a little fat with your meal. It doesn’t need to be a lot. In fatty
fish, the fat already comes filled with vitamin D.