Sunshiny Medicine - Why we should be both sun-safe and sun-loving.
I don’t think a day goes by where my inbox isn’t being hit with a research update on Vitamin D, and I'm not alone. During COVID times, it seems the whole world is learning about Vitamin D at a great speed of knots.
We know that every tissue and cell in the body has a vitamin D receptor; and immune cells, colon, breast, skin, and other cells in your body can all activate vitamin D locally. It’s thought that the purpose of this is to regulate cellular growth and a variety of genes. Consequently, a deficiency can be detrimental to pretty much every system in the body!
Although it's actions are widespread, common symptoms of Vitamin D deficiency include:
Muscular aches and pains
Getting sick easily or often/ recurrent infections
Fatigue
Chronic pain (often in bones)
Low mood and/or seasonal depression
Poor wound healing
Bones that break easily or low bone mineral density
General weakness
Isn’t Vitamin D deficiency just a problem for those that work inside?
Definitely not. In my experience, people working outdoors are VERY good at being sun-safe – slip, slop, slapping is part of the morning routine! This means that Vitamin D deficiency is surprisingly common with the demographic I work with (farmers) and is firmly on my radar, especially if someone is has any of the above symptoms or has a family or personal history of cancer, osteoporosis, autoimmune disease, cardiovascular disease or mental illness.
Food vs Sunshine vs Supps – What’s best?
For most people, sunshine trumps supplements and food-based sources of Vitamin D.
However, for those wearing culturally appropriate long clothing, the elderly, and those with dark skin, supplements are often necessary. It’s not just these groups that are at risk of a deficiency however – office/ indoor workers, shift workers, babies and children who are meticulously covered up, miners and as previously mentioned super sun-safe farmers are all at risk of Vit D deficiency.
Even though many foods are touted to be rich in Vitamin D (such as eggs, sunned mushrooms, lard, liver, fatty fish and ghee/ butter); the levels compared to sunshine are low, and we absorb Vit D MUCH better through the sun versus through food.
In fact, we get roughly 90-95% of Vitamin D via the skin, and only 5-10% through food. For comparison’s sake, about half an hour of sun exposure at midday in the summer sun will release a whopping 50,000 IU into our bodies (equivalent to 50 standard 1000iU Vitamin D capsules!).
Please also remember that the benefits of sunshine extend FAR beyond Vitamin D.
Sunshine has been shown to also confer a range of incredible immunomodulatory actions; modulate inflammation; elicit the release of helpful molecules such as nitric oxide, haem oxygenase and endorphins; and is crucial a healthy circadian rhythm/ body clock.
It’s also been discovered that skin can produce serotonin and transform it into melatonin in response to sunshine, and that many types of skin cells express receptors for both serotonin and melatonin. Fascinating stuff!
Is avoiding the sun as dangerous as smoking?
Well, according to a study conducted on 30 000 women over 20 years, yes! The researchers concluded that “Those who seek out the sun were generally at lower risk for cardiovascular disease (CVD) and noncancer/non-CVD diseases such as diabetes, multiple sclerosis, and pulmonary diseases, than those who avoided sun exposure. The results were dose-specific — sunshine benefits went up with amount of exposure.”
They concluded that avoiding the sun "is a risk factor for death of a similar magnitude as smoking."
There’s no debating that insufficient sun exposure is a real public health crisis. Chowdhury and his team looked at the serum Vitamin D data from 849,000 people and concluded that 12.8% of all US deaths (340,000/year) and 9.4% of all deaths in Europe (480,000/year) could be attributed to low serum Vitamin D.
Most public health messages of the past century have focused on the hazards of too much sun exposure, and it’s high time we start to discuss sun exposure in a more nuanced way.
We now know that UV radiation exposure accounts for only 0.1% of the total global burden of disease in disability-adjusted life years (DALYs), according to the 2006 World Health Organization (WHO) report. In contrast, the same WHO report noted that a markedly larger annual disease burden of 3.3 billion DALYs worldwide might result from very low levels of UVR exposure. This burden subsumes major disorders of the musculoskeletal system, various autoimmune diseases and life-threatening cancers.
So how much sunshine should we aim for?
The minimum effective dose can range from 5 mins/day to 30 mins/day, depending on time of the day, ethnicity, season, latitude, and UV (ultraviolet) index. For me, 5-10 mins of sunshine in the warmer months anytime between 7am-4pm is plenty as I’m fair skinned. In Winter I double this, and I might aim for more on a cloudy day, and less on a sunny day.
I often speak with my clients about what the optimal dose might be for them, given their location, ethnicity, their blood test results, the season etc. I sometimes encourage people to feel for the “flush”. When you feel the warm flush under your skin and your cheeks get a little rosy, you’re done! For most people, I would cap sun exposure (with no sunscreen or sun safe clothing) to 30 mins/day as a maximum.
What is the optimal level we want to see on a blood test?
This depends on the person’s health status and ethnicity, but I generally like to see levels between 80-120nmol/L in most clients. Adequacy in conventional circles is anything over 50nmol/L, which might be ok for bone health, but arguably entirely inadequate if the goal is a strong and balanced immune system, good mental health, cancer prevention, optimal fertility, great muscular health and robust metabolic health!
If you’re an ‘at risk’ individual for Vitamin D deficiency, post-menopausal, or experience the symptoms of low Vitamin D, please speak with your practitioner or GP about getting tested. This is one nutrient you do NOT want flying under the radar.
