Last summer we suggested some ideas to begin a healthy school or work year. Eat well, make good “sleep hygiene” a priority, move off the couch, take “me time” to recharge, have fun in the sun with friends in the bush or at the beach.
This summer we’ve been thinking about vitamin D. Summer is usually the time we can build up our Vitamin D supplies for the winter ahead, and enjoy the other benefits of sunlight. But the Wellington summer hasn’t produced much sun this year, so are we getting enough Vitamin D to stay healthy?
Benefits of sunshine
Research is starting to find a lot of ways that we can benefit from being out in the sun.
- Getting out into the natural light first thing in the morning (without sunglasses) helps regulate our circadian rhythm so we have energy during the day but can sleep at night. This is important even on a cloudy or rainy day. Spend 10-15 minutes outside as close to sunrise as possible, maybe incorporating some light exercise such as walking, stretching or tai chi. Or just sitting and being mindful – what can you see, hear, feel and smell?
- Sunlight helps prevent depression and improve mental health by increasing the production of serotonin, which promotes feelings of happiness and well-being. Serotonin also gives us more energy.
- Sun stimulates the production of nitric oxide, which relaxes blood vessels, improving circulation and blood flow. This can help regulate blood pressure.
- But sunlight is most well known for helping us produce Vitamin D
Benefits of Vitamin D
Vitamin D – a family of compounds that includes vitamins D1, D2, and D3 – is important for healthy bones and teeth and essential for a healthy immune system function, by regulating the absorption of calcium and phosphorus in your body.
- For growth, development and maintenance of healthy bones and teeth.
- May make severe flu and COVID-19 infections less likely. A recent review found that low vitamin D levels contribute to acute respiratory distress syndrome.
- May reduce risk of infections and autoimmune diseases, such as rheumatoid arthritis, type 1 diabetes, and inflammatory bowel disease.
- May regulate mood and reduce depression
- May support weight loss
Food sources of Vitamin D
Foods with natural Vit D include salmon, sardines, herring, canned tuna, cod liver oil, beef liver, egg yolk.
Note that fish and krill oils don’t contain Vitamin D – you need fish liver oils – cod or skate are best.
Vitamin D from sunlight
Your body produces this fat-soluble vitamin D naturally when it’s directly exposed to sunlight, under certain conditions.
Can we get adequate vitamin D from sunlight alone? Maybe not if you live in an area with high pollution, use sunscreen, spend most of your time indoors or have darker skin. The higher the levels of melanin, the less vitamin D your skin can absorb. These factors can increase your risk of vitamin D deficiency.
To produce Vitamin D from sunlight, there are certain conditions that need to be met:
- the sun needs to be at the right angle, more or less overhead – in NZ this is approximately 10am to 4pm, during the summer months. The rest of the year, the sun is too low on the horizon.
- our skin needs to be free from any type of block – this includes windows, zinc based sun blockers, chemical sunscreens and potentially air pollution.
- we need to have sufficient fat in our diet, so that there is enough cholesterol in the skin.
- the more melanin in our skin, the longer exposure we need – melanin evolved as a protection for long hours under tropical sun.
Safe sunbathing
Easier said than done in this part of the world. Our sun is harsher than in other places and we do have to be careful.
Once upon a time, we all emulated the girl in the Coppertone ad, and sun baked as much as we could. More recently, the fear of skin cancer has taken us maybe too far in the opposite direction. In these days of sunblock, and mandatory hats for every school child, we are at risk of Vitamin D deficiency.
Where is the happy medium that allows us to get the benefits of sun exposure without the risks?
If you love the outdoors and summer activities – swimming or surfing, playing or watching cricket, lounging at the beach, BBQs with the family – you are likely to get more sun exposure than you need for Vit D production. If you spend all that time covering up, you won’t get the benefits. If you don’t cover up, you risk burning, which is never beneficial. So we’re looking for two different tactics, depending on your colouring and the types of activities you favour.
Getting your daily dose of D
For this, you need to:
- Be in the sun when its overhead, but not at its hottest – maybe around 10am or 4pm.
- Sunbathe with no creams or sunblocks on your skin
- The more of your body you can expose, the less time you need to be out
- Start slow and build up, to avoid burning
- Avoid washing for a while afterwards, or a lot of the benefit will be lost
Sun protection
First, we need to remember that clouds may stop optimum Vit D production, but they do not protect against burning. Even on a cloudy day, you need to be UV aware.
Most people will be aware of the 5 ways to be sun-smart. If you’re out all day in the NZ sun, you will need a combination of approaches, not just one.
- Slip on sun protective clothing
- Slop on SPF50 (or higher) broad-spectrum, water-resistant sunscreen, starting 20 mins before going out, and reapplying every 2 hours
- Slap on a broad-brimmed hat
- Seek shade
- Slide on some sunnies
Three out of five of these we are fully behind.
But wearing sunnies habitually may block messages the sun is sending to your body, including the ability to gauge the threat the sun poses.
There are also some concerns about sunscreens. Anything that is put on the skin can be absorbed into the body. Many sunscreens contain compounds which may be carcinogenic. That is particularly dangerous if combined with a Vitamin D deficiency – Vit D being a key nutrient to protect against cancer.
According to this article by EWG (Environmental Working Group), ingredients that could be a problem include:
- aminobenzoic acid, trolamine salicylate – FDA says not GRASE (generally regarded as safe)
- oxybenzone, homosalate, octocrylene – European Commission says not safe
- avobenzone, cinoxate, dioxybenzone, ensulizole, meradimate, octinoxate (octyl methoxycinnamate), octisalate, padimate O, sulisobenzone – FDA says not enough data to assume safe
Safer Sunscreens
Mineral blockers such as zinc oxide and titanium dioxide are generally considered to be non absorbent, so safer, but check what other ingredients are added. Neither should be inhaled, so avoid spray or powder formulations. So far we haven’t found a brand that is primarily mineral based that doesn’t have one of the chemicals above, or other potentially problematic components, added.
Some safer creams, made from zinc oxide and plant (or plant derived) products, no chemicals :
- Young Living Mineral Sunblock – contact Barb for availability in Wellington
- Ethical Zinc sunscreens – stocked by Commonsense Organics
- Eco Glory Veil under makeup – stocked by Commonsense Organics
Let us know of any others you find.
More info about safer brands, homemade alternatives, essential oils to come
Vitamin D deficiency
On top of the fact that we are covering up and not getting much Vit D from the sun (in some cases), recent studies indicate that we need more vitamin D than previously thought. Though it is a delicate balancing act – too much vitamin D is also unhealthy. So it’s a helpful part of your self care routine to check your levels once a year or so.
Ideally, get your doctor to order a blood test and advise you on supplementation. They may recommend high dose vitamin D tablets or liquids.
Or it is a blood test you can self order. Go into your nearest SCL or other lab and ask for a self requested Vitamin D – 25(OH)D – test. See more info on the test here.
Your test results will likely say that the optimal range of Vitamin D is 50-150 nmol/L. But some other nutrition experts have different guidelines on the best amount to have. We recommend you do your own research to determine your optimal levels, but here is one example, from Dr Mercola:
- Deficiency = < 125 nmol/L [< 50 ng/ml]
- Optimal = 125 to 175 nmol/L [50 to 70 ng/ml]
- Higher levels for treating certain diseases – 175 to 250 nmol/L [70 to 100 ng/ml]
- Excess = > 250 nmol/L [> 100 ng/ml]
If you need supplementation, use cod liver oil or a good quality, high dose D3 supplement. Daily dose approx 2000-5000 IU.
The bottom line on Vit D
- Vitamin D has many potential benefits. It may reduce the risk of certain diseases, help improve mood, reduce depression and help with weight management.
- It’s hard to get enough vitamin D through sunlight and diet alone, so ask a healthcare professional for a blood test and consider taking a vitamin D supplement.
More resources
- Dr Mercola’s vitamin D resource page
- Chris Masterjohn on studies of Vitamin D levels and Covid19 –
brooklynwellness.nz 