May 26th, 2026

Vitamin D and the Winter Months
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Vitamin D is important for:
 

• bone growth and strength
• muscle health
• our immune system
• wound healing

 
The main way of obtaining vitamin D is to produce it ourselves by exposing our skin to the sun.  In the winter it’s hard to get enough direct sunlight to maintain our vitamin D levels. If our vitamin D levels are low we can be at risk to a wide variety of health issues, including:
 

• bone diseases (eg, rickets, osteoporosis, hip fractures)
• cardiovascular diseases (eg, coronary heart disease, heart failure, stroke)
• infectious diseases (eg, tuberculosis, acute respiratory infections)
• altered immune function (eg, rheumatoid arthritis, Type 1 diabetes)
• cancer (eg, colorectal, breast)

 
You may be more at risk to low levels of vitamin D if you:
 

• have a dark skin and are of Maori, Pacific Island, African or Indian descent
• have a gut condition like Crohn’s or Coeliac disease which prevents you from absorbing vitamin D.
• cover your skin with cloths for cultural or religious reason
• avoid the sun and always apply sunscreen if outside no matter what time of the day or year.
• are elderly, disabled, immobile and spend most of your life inside.
• are a baby, teenager, pregnant or breastfeeding as you will require higher levels of vitamin D.

 
Signs you may have low vitamin D levels include:
 

• cramps
• aches and pains in your muscles
• repeated colds and flues

 
 
 
When exposure to sunshine is limited, especially in the winter in the South Island, we may need to find other sources of vitamin D, eg food.  Foods containing vitamin D include:
 

• fatty fish eg salmon, herring, mackerel, sardines, tuna
• eggs
• fortified milk and yoghurts
• some margarines
• butter
• liver

 
You may need a vitamin D supplement if you can’t get outside regularly and your levels are low.  Discuss supplements with your Doctor, they are not recommended for everyone.