I absolutely love summertime! What’s not to love about summer? The sun shines brighter and there are so many fun outdoor activities to do with my family. While I love all outdoor activities, the best part of having fun in the sun is reaping the benefits of vitamin D. It’s true the sun is one of the best ways you can get optimal levels of vitamin D from the sun. However, exposure to the sun does come with risks. So, how do you get vitamin D without sunlight? Well, I am about to let you in on my secret for getting optimal levels of vitamin D without exposure to the sun.
Before I give away this secret on how to get vitamin D without the sun, let me tell you that vitamin D insufficiency was one of the most common deficiencies I saw as a doctor. In fact, if you aren’t already supplementing your vitamin D, your levels are likely low of this very essential vitamin. Nearly 1 billion people around the world are vitamin D deficient.1 It doesn’t have to be this way!
Vitamin D is needed at every level for whole-body health. Every single type of tissue in your body has receptors for vitamin D. Your bones, heart, brain, muscles, immune system, you name it, all require optimal levels of vitamin D to function. Vitamin D is also the only vitamin that also functions as a hormone in your body, making it even more important to be sure you are not deficient or insufficient in this all-important micronutrient. Let’s talk more about this important vitamin and what it does in your body.
What is Vitamin D?
Vitamin D is a fat-soluble vitamin that is found naturally in food. Your body also has the ability to create its own vitamin D when it is exposed to sunlight. Because it’s a fat-soluble vitamin, your body uses what it needs and stores the excess amounts in fat cells instead of removing it through your urine the way it does with water-soluble vitamins such as B vitamins.
Where We Get Vitamin D Is Important
Vitamin D is found in fatty fish, egg yolk, whole cow’s milk, some grains, and organ meats such as liver. However, some vitamin D-rich foods such as canned tuna, dairy products, and mushrooms are inflammatory or toxic.
Grains contain gluten. Gluten is an inflammatory food that leads to autoimmune disease. The problem with dairy is that it contains lactose and casein. Many people have a sensitivity to lactose and casein has a molecular structure similar to gluten. I recommend that everyone remove gluten and dairy from their diet which makes it even more challenging to get enough vitamin D.
Vitamin D Is Unique From Other Vitamins
Vitamin D is a unique micronutrient in a couple of different ways. First, it is one of two vitamins that your body can make on it’s own, along with vitamin K. Remember what I said about getting vitamin D from sun exposure? Well, the sun itself doesn’t give your body vitamin D. When your body is exposed to the sun, the sun’s ultraviolet B (UVB) rays hit cholesterol in the skin cells, providing the energy for your body to make its own vitamin D3.2 Secondly, vitamin D is the only vitamin that also works as a hormone.
The Types of Vitamin D
There are two types of vitamin D: Vitamin D2 and vitamin D3. The primary difference between the two is that vitamin D2 comes from plant sources and vitamin D3 comes from animal sources such as fatty fish. Vitamin D3 is the bioidentical form of vitamin D that is formed in your skin when it is exposed to sunlight. Vitamin D3 is synthesized in the body from cholesterol, which is activated by UV rays in sunlight. 3 Vitamin D3 is the better form to consume because it has been shown to increase vitamin D levels in the blood more effectively than vitamin D2.4
How Much Vitamin D You Need
The recommended daily allowance (RDA) for vitamin D is 800 IUs per day. However, there’s a difference between the RDA and Optimal Daily Intake, which are higher than the RDA. I recommend 5,000 IUs per day to maintain optimal levels. I’ll discuss vitamin D insufficiency more later and how you can get optimal amounts of vitamin D3 without sun exposure. Now, let’s talk about the role this powerhouse micronutrient plays in your body.
Benefits of Vitamin D
Over 50,000 chemical reactions in your body require the presence of optimal amounts of vitamin D in your blood. Vitamin D supports bone health, heart health, and your immune system. Let’s look closer at what vitamin D does.
Regulates Calcium Absorption
Vitamin D plays a vital role in facilitating healthy bones, but not directly. As I said earlier, vitamin D is a hormone, however it is better known as a vitamin. This is one area vitamin D acts as a hormone.
Hormones are chemical messengers that regulate functions in your body, such as insulin regulating glucose in the blood or serotonin regulating the amount of cortisol in your body when it’s under stress. Vitamin D works as a regulator of calcium, a mineral that builds bones, enables your blood to clot, your muscles to contract, and your heart to beat. Even if you get enough calcium in your diet, your body will not absorb that calcium if you don’t get enough vitamin D.
Supports Your Immune System
If you’re finding yourself under the weather too often, that may be a sign that your vitamin D levels are suboptimal. Vitamin D works hand-in-hand with your body to modulate immune activity. Think of vitamin D as a light switch in your body, turning on or off genes and processes that your body needs for a healthy immune system.
Active vitamin D is sent to different areas of your body, including your bones, intestines, colon, brain, and immune cells, which all have Vitamin D receptors. The active vitamin D binds with these receptors and promotes vitamin D responsive genes, essentially turning them on to facilitate a healthy immune system response.
Promotes Brain Health
Vitamin D is often referred to as the “sunshine vitamin,” however what you may not know is that new research shows that vitamin D could support brain health and cognitive function.5
You might notice that your mood changes during the cold winter months. Unfortunately, if you live in an area that is cold and dreary in the winter, you probably spend a lot of time indoors, which lowers your ability to get vitamin D from the sun and increases your risk of a vitamin D deficiency.
Seasonal affective disorder (SAD) is very common in the winter months and research shows there is a direct link between a lack of UV rays from sunlight to produce vitamin D in your skin and SAD. A new study by the University of Georgia linked low vitamin D levels with greater risk of seasonal depression, which affects up to 10% of the US population though the fall and winter months.6
Getting enough vitamin D without the sun can be challenging. Before I let you in on my best tool to ensure you’re getting enough vitamin D, let’s talk about the signs of a vitamin D deficiency.
Symptoms of a Vitamin D Deficiency
Overcoming the high rates of vitamin D insufficiency is not easy. That is because it is difficult to maintain sufficient levels through diet and lifestyle. This can be due to not enough sun exposure, not eating enough vitamin D rich foods, or fat malabsorption.
Since vitamin D is a fat-soluble vitamin, If you have a leaky gut caused by inflammatory foods such as gluten, infections, medications, or toxic overload, your ability to absorb nutrients and vitamins may be severely compromised.
Severe vitamin D deficiency causes rickets in children, weakness in muscles, pain in bones and deformities in joints. Lack of vitamin D in adults is not as obvious as it is in children.
I just mentioned depression is a sign of a vitamin D deficiency, however there are a few more to look out for. Here some some other signs you could be vitamin D deficient:
- Frequent infections and illnesses – One of vitamin D’s most important roles is supporting your immune system. If you often feel under the weather during the cold and winter months, low levels of vitamin D could be the reason why.
- Constant fatigue – This is often overlooked as a sign of sub-optimal vitamin D levels. However, several studies have shown that people with low levels of vitamin D have a higher level of severe fatigue.7
- Bone and back pain – I discussed earlier how vitamin D supports bone health. If your bones aren’t getting the support they need from vitamin D, they can become brittle.
- Muscle weakness, cramps – Remember that vitamin D helps your muscles contract. It can be difficult to know what is causing your muscle pain, especially if you’re active. However, if you have the occasional discomfort in your muscles, it could be a sign of a vitamin D deficiency.8
Sub-optimal vitamin D levels are incredibly common. The troubling part is that most people don’t know they have an insufficient amount of vitamin D . Fortunately, getting enough vitamin D is easy if you eat vitamin D-rich foods such as fatty fish or get vitamin D from the sun.
If you want to test your nutrient levels at home, I recommend using a home micronutrient test fromLetsGetChecked. You can choose between the essential vitamin test, which tests the levels of vitamin D, B12, and E, a mineral test, or the full micronutrient test, which tests for the vitamins I mentioned and copper, selenium, zinc, and magnesium. The results are available online so you can share them with your functional medicine doctor.
However, there are some dangers of sun exposure. Let’s talk about those.
Dangers of Sun Exposure
Have you ever had a severe sunburn after spending the day in the sun? This is caused by too much time in the sun. While you can’t see UV rays, they do go through your skin.
The outer layer of your skin is the epidermis and the inner layer is the dermis. Your nerves and blood cells are located in the dermis. The epidermis contains a pigment known as melanin, which is what protects your skin and creates vitamin D. This defense is what causes your skin to get darker.
Too much sun exposure allows these dangerous UV rays to reach the inner layers of your skin. You probably know this as a sunburn. Besides being extremely painful, sunburns damage your skin cells and cause them to die.
Too much sun exposure can do more than just burn your skin. Here are a few more risks of getting too much sun exposure.
Too much sun exposure makes your skin age faster than normal. This is known as photoaging. The UV radiation that affects the skin is composed of two different types of waves, UVA and UVB. When UV rays hit the skin, they damage its DNA, and cells in the dermis scramble to produce melanin.9 Remember, this is what gives your skin that tan appearance, yet it is really just your skin attempting to block UV ways from getting through. Signs of photoaging are wrinkled, tight, or leathery skin and freckles.
Skin cells with melanin can begin to clump with too much sun exposure.10 This is what causes freckles, moles, and skin tags.
Weakened Immune System
When you get sunburnt, your immune system produces more white blood cells to help create new skin cells. This causes your immune system to work harder. When your immune system is overworked, it can’t jump in when it is needed.
Melanoma is the most severe form of skin cancer, however it’s not as common. Constant exposure to UV radiation from the sun, sunlamps, and tanning booths puts you more at risk of developing skin cancer.11 If left untreated, it can spread to other parts of your body. To protect your skin while in the sun you should wear a sunscreen that blocks against UV rays and has a sun protection factor (SPF) of 15 or higher. I recommend sunscreen that is mineral based and natural so you aren’t exposing your skin to parabens, toxins, or synthetic chemical fragrances.
Damage to Your Eyes
You’ve probably been told not to look directly into the sun. There’s a reason for that. Sunlight can take a heavy toll on your eyes if you don’t protect them. UV rays can burn the outer layer of your cornea, which can lead to blurred vision, watery eyes, and even cataracts, which may even lead to total blindness.12 If you’re going to be in the sun, wear sunglasses that block both UVA and UVB rays. Most sunglasses, even cheaper ones, block both types of UV rays. However it’s always a good idea to check the tag to make sure.
Now that you understand the dangers of the sun, I’m so excited to tell you about my best tool to get vitamin D without the sun.
Climate and Vitamin D
Your body can only synthesize vitamin D3 from UVA rays from the sun. However, the further away from the equator you live, the lower the amount of UVA rays you get from the sun to make vitamin D in your skin. For example, if you live in Minnesota, you are not exposed to the same level of UV rays that you would in Texas. Let me tell you why.
UVA rays have a wavelength of 315 to 400 nanometers, however they aren’t as damaging as UVB (280-315 nm) and UVC (100-280 nm) rays. UVC rays are completely blocked by the atmosphere and never make it to the Earth’s surface. UVB rays are biologically active, but cannot penetrate beyond the top layers of the skin. The UVA wavelengths are so long they can penetrate deep into your skin and into cholesterol to make vitamin D3.
The closer you live to the equator, the shorter distance they have to travel through the atmosphere. Remember, the equator is the closest point of the Earth to the sun.
Get Vitamin D Without the Sun
Getting enough vitamin D without the sun is difficult since one of the only two sources of vitamin D is sunlight. The other is through diet. The problem with that is that many foods that contain vitamin D are inflammatory or toxic, such as canned tuna, dairy products, and grains. Wild-caught salmon is one of the most vitamin-D rich foods available, yet it only contains 570 IUs of vitamin D per 3 ounces. That would mean you could eat 6 ounces of salmon for every meal and still not reach the optimal level of 5,000 IUs per day.
If you’re wondering how to ensure you’re getting vitamin D without the sun, I have great news for you. A high-quality Vitamin D3 supplement is the best way to get vitamin D without the sun. Vitamin D3 is the form that is created in your skin when it is exposed to the sun. It also increases the levels of vitamin D in your blood more effectively than other forms of vitamin D.
The Best Vitamin D3 Supplement
I personally formulated my vitamin D3 supplement to include vitamin K2. The tandem of D3/K2 works together to ensure calcium absorption reaches your bones, instead of your blood.
Due to the stability of vitamin D it can be taken in a couple different forms. You can get Vitamin D3/K2 in liquid form. Each drop supplies 1,000 IUs of vitamin D to support your bone health, heart health and immune system. Liquid Vitamin D3/K2 is easy to use and can be added to your favorite beverage or food. Vitamin D3/K2 in capsule form offer 10,000 IUs of bioavailable vitamin D3 in each capsule to ensure proper absorption. Vitamin D3/K2 has 45 mcg to discourage calcium buildup in the arteries and soft tissue.
Since Vitamin D is a fat-soluble vitamin, it gets stored in our body and too much can build up over time. If you are supplementing with high doses (over 5,000 daily IU), I recommend getting your blood levels checked every 3 -6 months while supplementing. You can test your vitamin D levels at home through My Labs for Life.
Sub-optimal vitamin D insufficiency is a major problem around the world. Getting enough vitamin D without the sun is challenging since it is the way your body naturally produces this essential vitamin. While some sun exposure is healthy and totally recommended, however too much of a good thing can be a bad thing. Take care of your skin when you’re in the sun and be sure to supplement with vitamin D3.
- Vitamin D Deficiency- An Ignored Epidemic. Dr Zahid Naeem, MBBS, MCPS, DPH, FCPS. International Journal of Health Sciences. 2010.
- Sunlight and Vitamin D. Matthias Wacker and Michael F. Holick. Dermato-Endocrinology, vol. 5. 2013.
- Vitamin D2 vs. D3: What’s the Difference?. Atli Arnarson BSc, PhD. Healthline. 2018.
- Short and long-term variations in serum calciotropic hormones after a single very large dose of ergocalciferol (vitamin D2) or cholecalciferol (vitamin D3) in the elderly. Elisabetta Romagnoli. The Journal of Clinical Endocrinology and Metabolism, vol. 93. 2008.
- Vitamin D and cognitive function. Maya Soni 1. Scandinavian Journal of Clinical and Laboratory Investigation: Supplementum vol. 243. 2012.
- Low Levels of Vitamin D Can Increase Your Risk of Seasonal Affective Disorder. Monroe Clinic. 2021.
- Vitamin D deficiency and fatigue: an unusual presentation. Elisabetta Romagnoli. SpringerPlus, vol. 4. 2015.
- More than healthy bones: a review of vitamin D in muscle health. Maya Soni 1. Therapeutic Advances in Musculoskeletal Disease . 2015.
- Photoaging: What You Need to Know About the Other Kind of Aging. Skin Cancer Foundation. 2019.
- Effects of Sun Exposure. American Academy of Family Physicians. 2020.
- Sunlight Risk Factors. National Cancer Institute. 2021.
- What Toll is the Sun Taking on Your Eyes?. USC Roski Eye Institute. 2021.