Vitamin D – The Sunshine Vitamin

Isn’t it lovely to feel warmer weather slowly encroaching upon us?  Getting out of bed without your toes freezing is certainly a plus, and the thought of all the delicious summer fruits to come…. yum! Leaving behind all the comfort foods of winter and embracing the delights that spring has to offer.  I’m looking forward to being able to be outdoors more, enjoy the warm sunshine and get my veggie garden planted for summer. 

While many of us are aware of the dangers of overexposure to the sun, less well known is the fact that exposure to the sun is one of the primary ways our bodies obtain vitamin D. Our skin can produce vitamin D when exposed to UVB rays. Vitamin D is crucial to the health of our bones, as it helps our bodies absorb the calcium from our food that our bones need to maintain their strength. It’s also important for healthy muscle function to prevent spasms and cramps. Other roles include promoting a healthy immune system, reducing inflammation, and enhancing glucose metabolism and cell growth.

Unfortunately, there aren’t many foods that contain vitamin D and those that do, only have small amounts.  Some of these include oily fish such as canned tuna and salmon, eggs, dairy and liver. Who remembers being given cod liver oil as a child?  Severely low levels of vitamin D can cause rickets (a bone-softening condition causing bowlegs and knock knees) in children, osteomalacia (soft, brittle bones), osteoporosis and bone and muscle pain in adults. Rickets is very rare these days, as most of us get enough vitamin D to prevent it, but according to the NZ Nutrition surveys, about one-third of the population have less than the recommended levels of vitamin D. 

So, we’re doing a great job of ‘slip, slop, slap’, but a little exposure to the sun, without sunscreen on, each day is important, 5 – 15 minutes may be all that you need, depending on the time of year.  In summer, 6 – 8 minutes, before 10 am and after 4 pm, may be enough, but in winter we need about 30 minutes in the midday sun.  Unfortunately sitting by a sunny window doesn’t do the job, as glass stops the UVB rays we need to make vitamin D. Due to an increased risk of cancer, a sunbed is not recommended.

How much sun exposure you need depends on a few factors like:

  • Skin colour – the darker your skin, the more sun exposure you will need
  • Age – as we age our ability to produce vitamin D declines
  • The quantity of vitamin D-rich foods we consume
  • Certain medications are photosensitising and make our skins more sensitive to the sun
  • Latitude – living in lower latitudes increases our requirement
  • Risk of skin cancer & certain medical conditions

So, enjoy the outdoors this spring and top up your vitamin D levels.  If you are concerned that you are not getting enough vitamin D, you can have your vitamin D levels tested and a supplement may be helpful if your levels are low.

If you would like help with creating new routines and learning how to prioritise your health, e-mail me at paula@drkathleen.co.nz for an appointment.

Paula Southworth
Registered Nutritionist (NZ) & Health Coach
(BSc Nutrition and Sports Science)
Member of the Nutrition Society of New Zealand

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