Most health-conscious people have heard that vitamin D is important and know that sun exposure is a great way to get more of it. It’s not uncommon to hear people say they’re “getting a little vitamin D” or “soaking up some vitamin D” when referring to working, playing, or exercising outdoors. But how much sun exposure is enough? Does everyone need the same amount? If you spend time in the sun, are vitamin D supplements unnecessary? Because there are many factors that determine the answers to these questions, there is no “one size fits all” approach. Vitamin D plays a very significant role in human health. At the same time, given that vitamin D is a fat-soluble nutrient and acts as a hormone in its active form, there is also a risk of toxicity that is greater than for other vitamins and minerals. The best way to determine if you’re getting enough vitamin D – but not too much – is to get your vitamin D levels tested on a regular basis.
Immune Regulator, Mood-Stabilizer, Bone-Strengthener, & More!
Why is vitamin D so important in the first place? Because it’s actually more like a hormone in its active form and plays a vital role in many aspects of health including its most well-known function – bone health. However, vitamin D is also important for cardiovascular health, mental health, immunity, overall health, and even genetic expression. This wide range of functions is due to the (pro) hormone form of vitamin D being tasked with making many enzymes, neurotransmitters, and hormones. Recent studies have also shown that low vitamin D could be a factor in the development of type 2 diabetes. Supplementation may help with glucose regulation and weight loss due to vitamin D’s effect on the hypothalamus. Low vitamin D status also appears to be a factor in mortality rates in heart disease patients, autoimmune diseases, asthma, cancer, cognitive impairment in the elderly, gestational diabetes, and preeclampsia.
Factors that Influence Vitamin D Production & Individual Need
While most healthy adults need about 5,000-10,000 units of vitamin D per day, there are many factors that can influence this. For example, certain chronic diseases, such as inflammatory bowel diseases and other malabsorption disorders, can double the amount needed in some individuals. Those following a vegetarian diet and those with kidney disease are also at risk for deficiency. While sun exposure is one of the best ways to get your vitamin D, it’s difficult to estimate exactly how much is made during time outdoors. Some experts say that fair-skinned individuals make about 10,000 units from being out in the sun for 10 minutes during mid-day in shorts and a t-shirt. But many factors can decrease this amount including:
- Wearing sunscreen (anything above SPF 8)
- Showering immediately before sun exposure (washes off oils helpful for absorption)
- Overcast weather
- Clothing/more skin covered
- Darker skin tone
- Time of year (August-December for those above the equator)
- Geographical location (northern hemisphere)
- Other nutrient deficiencies (ie. vitamin C and certain minerals)
Even if you don’t think you’re at risk for vitamin D deficiency, it is still wise to get tested. Especially if you are experiencing muscle or bone pain, have an autoimmune disease, allergies, tinnitus, depression, or get sick often. According to the CDC, about 30% of the population has an outright vitamin D deficiency. But when you take sub-optimal levels into consideration as well, the number is probably more around 50% and close to 95% among the elderly. Even though an individual may not be medically diagnosed with vitamin D deficiency with levels above 12 ng/ml and especially above 20 ng/ml, the most current research shows that levels should optimally fall between 50-70 ng/ml or even higher in certain cases, such as in autoimmune disease treatment and cancer prevention.
When Is Supplementation Warranted?
Supplementation may be needed if you are at risk for deficiency due to environmental factors, darker skin tone, chronic illness, or if you simply don’t have a lifestyle that allows adequate sun exposure. Foods such as eggs, fish, liver, and fortified foods are good sources of dietary vitamin D. Generally, though, foods sources alone will not adequately keep vitamin D stores high enough. The best way to ensure that your levels are optimal is to get tested through your doctor or an independent lab, such as the vitamin D council. It is best to get tested around August (when levels are typically at their highest) and again around February (when they are typically at their lowest). Re-testing every 3-6 months will ensure adequate and safe dosing during supplementation. Holtraceuticals offers vitamin D3 (twice as bioavailable as D2) in both 50,000 IU (only take under doctor’s supervision as higher doses are not intended for daily, ongoing use) and 5,000 IU. Additionally, a combination vitamin D and vitamin K formula is also available, as the two often work together to carry out important functions, such as bone formation and immune-regulation.