Is the change of season making you sneeze?

Your ability to avoid colds and flu is related to vitamin D. Vitamin D levels in your blood fall to their lowest point during winter due to lack of sunlight. Vitamin D is essential for the body to produce its own antibiotics so a person with a low vitamin D blood level is more vulnerable to contracting colds, influenza, and other respiratory infections. Studies show that children with rickets, a vitamin D-deficient skeletal disorder, suffer from frequent respiratory infections, and children exposed to sunlight are less likely to get a cold. The increased number of deaths that occur in winter, largely from pneumonia and cardiovascular diseases, are most likely due to vitamin D deficiency.

So can’t I just eat more vitamin D rich foods to avoid colds this winter?

It is very difficult to get adequate amounts of vitamin D from your diet unless you are eating large amounts of offal, oily fish and seafood. Some estimates have been made on food composition with daily intakes of vitamin D between 2-3 μg /day (80-120 IU) for adults (Baghurst & Record 2002). This is well short of the 4000IU that we’d recommend for adults to achieve optimal levels of vitamin D (see here for how we justify this dose)

Hang on – I thought I could still get my vitamin D dose by getting outside in the sun?

Sun exposure on the skin is the other option for boosting your vitamin D levels. Vitamin D is produced by your skin in response to exposure to ultraviolet B rays from the sun. But these rays cannot penetrate glass, sun tan lotion, clothing, or dark skin to effectively generate vitamin D in your skin. In most parts of New Zealand and Australia a “vitamin D winter” occurs for around 4-6 months in which weather conditions make it impossible to produce enough vitamin D from sunlight.

The largest study of its kind (with over 19,000 subjects) from the Archives of Internal Medicine (2009) gave a summary:
“The findings of our study support an important role for vitamin D in prevention of common respiratory infections, such as colds and the flu. Individuals with common lung diseases, such as asthma or emphysema, may be particularly susceptible to respiratory infections from vitamin D deficiency.”

If you’re looking to optimise your vitamin D levels to reduce your risk of colds and flus this winter make sure you keep up your cod liver oil.

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My name is Dave Liow. I am an exercise physiologist who has specialised in helping people get healthier for the last 20 years. I’ve been lucky enough in my career to work with world class NZ athletes, hold a health science senior lectureship, and help improve the health of a wide range of people over this time.

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I’ve been a member of the Weston A Price Foundation (WAPF) since 2006. I was lucky enough to organise a tour of Sally Fallon to New Zealand in 2007 and absolutely loved picking her brains. WAPF introduced me to the many benefits of cod liver oil. I imported Green Pasture cod liver oil into New Zealand to help my patients increase their vitamin D levels. So many of them got great results and told others that I ended up setting up a business to keep up with the demand and started in Wellington. My healthy kids have had cod liver oil since they started eating solids. My wife and I take cod liver oil every morning. My mum uses cod liver oil to combat her osteoporosis. My friends have used cod liver oil to beat the winter blues, for their pregnancies, and to help grow healthy kids.

Warning: This site only sells Green Pasture cod liver oil.

We send to all NZ addresses by FREE signed courier delivery. See here for details

I wouldn’t give anything else to you or my friends and family.
To the best of my knowledge Green Pasture is the only brand of cod liver oil that uses lactofermentation, rather than harsh cleaning and deodorizing using heat and chemicals, and only the natural vitamins that come from the fish.

Almost all other brands of cod liver oil are processed to remove all the vitamins A and D and then non-fish (lanolin) or synthetic vitamins A and D added back in. These products should be completely avoided as the synthetic versions of A and D are toxic.
The process that is used to make Green Pasture cod liver oil is time consuming, expensive and absolutely best practice. This cod liver oil isn’t the cheapest, but it’s the best. If you’re going to invest in your health, make it a worthwhile investment. Read this to see why this is the cod liver oil for you.