Everything You Need To Know About Vitamin D

The summer is coming! Stay calm everybody, stay calm. The sun is the most natural source of vitamin D. Most people lack this vitamin during wintertime because it’s mainly dark and grey outside.

I live in The Netherlands, meaning it’s mainly rainy and dark outside during the year. In the summer, everybody rushes to the beach or goes outside to enjoy a few days of sunny heaven. During these days, the body stores the excessive vitamin D it gets from the sun in the fat storage of the body for weeks/months.

Getting enough vitamin D is important for the typical growth and development of bones and teeth. It also helps improve resistance to certain diseases. Research suggests that low levels of vitamin D are linked with an increased risk of Multiple Sclerosis (MS). MS is a chronic disease of the central nervous system. Besides this, insufficient levels of vitamin D have been linked to an increased risk of cardiovascular diseases. This includes strokes, heart failure, and hypertension. I hope this motivates you to read this blog until the very end :).

Everything You Need To Know About Vitamin D

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In Short

In short, this blog will prepare you with everything you need to know for the upcoming summers. Enough chatting, let’s get to work. Everything You Need To Know About Vitamin D coming right up!

Understanding Vitamin D Deficiency

In this very first chapter, we’re discussing what vitamin D actually is. We will also cover the causes of vitamin D deficiency. Additionally, we will highlight the possible risk factors of vitamin D deficiency. Read this paragraph with full focus. It will provide you with the basic knowledge you need about vitamin D. (No, don’t skip the rest.)

What Is Vitamin D?

Vitamin D helps regulate the amount of calcium and phosphate in the body. These nutrients are essential for the body, as they keep bones, teeth, and muscles healthy. The government recommends people to supplement vitamins during the winter and autumn, as vitamin D is naturally produced by the human body with the influence of the sun. Where I’m from, the sun is nowhere to be seen in the winter days.

Also, laboratory studies have shown that vitamin D can reduce cancer cell growth, help control infections, and prevent inflammation. Many organs have vitamin D receptors, suggesting that vitamin D is even more important than we know now.

Causes of Vitamin D Deficiency

A lot of people suffer from vitamin D deficiency. This is mainly because you won’t feel any significant changes in your body, and other people won’t see any changes either (except for looking a bit pale and being in a bad mood). However, inside our body happens a lot when it’s deficient in vitamin D.

The main cause of vitamin D deficiency is not getting enough sunlight on your bare skin. So if you’re studying for an important upcoming test while reading this, go to school people. Try taking a break for a short walk if you feel like it. This provides your body with the needed vitamin D. But besides the sun, other factors may also influence whether you’re in a deficiency or not:

• Darker skin pigment, if you have a darker skin, vitamin D deficiency is more likely. This is mainly because pigmentation reduces vitamin D production in the skin.
• Malnutrition. As you might expect, malnutrition leads to a vitamin D deficiency, because the body doesn’t get its needed nutrients.
• Kidney or liver failure. The body might get enough vitamin D, either from supplementation or sunlight, but doesn’t handle it well due to kidney or liver failure. Consult your doctor if you feel like you experience kidney or liver problems.
• Certain medications, such as laxatives, steroids, cholesterol-lowering drugs, and seizure-preventing drugs.
• Certain kinds of cancer, such as lymphoma.
• Family histories of vitamin D deficiency. In the last case, there’s not much you can do besides contacting your doctor.

Health Conditions on Vitamin D Absorption

Furthermore, certain health conditions can influence the absorption of vitamin D, leading to potential deficiencies. These conditions include the following (a warning: the following paragraph is quite difficult for a normal person, as most of the used terms are very unusual. Feel free to skip it if you’re sure that you don’t experience these kinds of things):

• Inflammatory Bowel Disease (IBD): This includes conditions like Crohn’s disease and ulcerative colitis. Inflammation in the digestive tract can interfere with nutrient absorption. This includes vitamin D.
• Celiac Disease: Individuals with celiac disease suffer from an autoimmune disorder triggered by gluten consumption. People with celiac disease might have their small intestine’s inner lining harmed. This harm can make it harder for their body to take in important nutrients. They might struggle to absorb essential nutrients like vitamin D from the food they eat.
• Cystic Fibrosis: A genetic disorder that affects the lungs and digestive system. Cystic fibrosis can disrupt the body’s ability to absorb fat-soluble vitamins like vitamin D. This is due to pancreatic insufficiency and other digestive issues.
• Bariatric Surgery: People who undergo bariatric surgery for weight loss may face challenges in absorbing vitamin D. This difficulty arises due to alterations in the digestive tract. These changes can reduce the surface area available for nutrient absorption.
• Small Intestine Resection: Surgical removal of sections of the small intestine is often necessary in conditions like Crohn’s disease. It may also be required due to other intestinal complications. This can diminish the area available for nutrient absorption. As a result, it can potentially lead to vitamin D deficiency.
• Pancreatic Conditions: Conditions such as exocrine pancreatic insufficiency are problematic. In this condition, the pancreas does not produce enough enzymes to properly digest food. Consequently, this can hinder the absorption of fat-soluble vitamins like vitamin D.

Okay, breathe out. From now on, we’ll keep it simpler. Let’s discuss symptoms that you might be in a deficit.

Recognizing Vitamin D Deficiency

This paragraph goes over the common symptoms of vitamin D deficiency. It is divided into a common symptom section and a less common section. If you’re experiencing any of these things, it is recommended to talk to your GP.

Common Symptoms

The first and most common symptom of a vitamin D deficiency is fatigue. We’re all fatigued sometimes, but if you’re fatigued the whole time without a significant reason, it might be something serious. A symptom we often overlook is a vitamin D deficiency.

In short, vitamin D is vital to bone health. An insufficient amount of vitamin D can cause bone and muscle weakness. This bone and muscle weakness results in abnormal amounts of fatigue. Your body needs to work harder to get things done. It cannot rely on muscle and bone strength.

A study on young women investigated the link between fatigue and low vitamin D levels. It found that women with less than 29 ng/ml were more likely to report excessive fatigue than those with more than 30 ng/ml. Normal vitamin D levels are between 20-40 ng/ml, but some groups suggest that 30-50 ng/ml is more optimal. This study supports the latter statement.

Bone Pain

The second one is bone pain. Duh, look at the previous paragraphs. No seriously: vitamin D is essential for bone health and strength. Lack of vitamin D eventually leads to extreme amounts of fatigue or even worse. Another cause of bone pain is rheumatoid arthritis. Vitamin D deficiencies may lead to this disease, as a 2012 study confirmed.

One of the first things a doctor does when someone has a fracture is checking their vitamin D levels. If the vitamin D levels are too low, the doctor will probably prescribe vitamin D supplements.

Muscle Weakness

A third symptom of vitamin D deficiency is muscle weakness, muscle aches, or muscle cramps. If it takes you forever to get active again after a workout, it might be a symptom of vitamin D deficiency. If you feel real pain after it, it might be a symptom of vitamin D deficiency. Nociceptors are the nerve cells that store vitamin D in their receptors. These cells are the ones that sense pain in the body.

Previous studies have shown that there is a correlation between chronic pain and low vitamin levels. This research, for example, found that 71% of people with overall chronic pain suffer from vitamin D deficiency.

Mood Changes

The 4th one is one that most people know or have heard about. Mood changes, like depression. There is a strong correlation between vitamin D deficiency and mood changes. However, research suggests that it is not very common in young adults.

Mostly elderly and people with darker skin fall into this category. Research on the effects of vitamin D on mental health concluded that 65% of those who showed signs of depression. These individuals had low levels of vitamin D.

Not saying that a deficiency in vitamin D does not impact younger people like us. The main function of vitamin D in young people is developing strong, healthy bones and muscles. It also prevents rickets. Rickets is a bone disease, a consequence of vitamin D deficiency over a long period.

Less Common Symptoms

These are the symptoms that are less common, but are still possible whenever you’re in a vitamin D deficiency.

Slow Healing

Our 5th symptom is getting sick and healing slowly. Another function of vitamin D is making sure the immune system works optimally. Studies have shown that vitamin D can be helpful in battling respiratory infections. Those are inflammations in your respiratory system (nose, mouth, and airways) caused by a virus or bacteria. On the other side, being sick often has a lot of other causes.

Bruises, cuts, and other wounds may take longer to heal when you’re in a vitamin D deficiency. Vitamin D helps the immune system to fight off infections and assists in skin repair, promoting faster healing.

A study in Portugal found that patients with leg ulcers who were treated with vitamin D were able to reduce the size of the ulcer by 28%. This reduction occurred after taking vitamin D supplements.

Hair Loss

Let’s go on to the last one because it’s getting boring at this point. The symptoms after this one will be listed in rapid-fire. But first, let’s discuss hair loss because it’s also a symptom of vitamin D deficiency. In simple terms, vitamin D plays a role in hair health. This is because it is involved in the growth and development of hair follicles. Hair follicles are tiny structures in the skin where hair grows. Vitamin D helps regulate the processes that control how hair follicles function.

When there’s not enough vitamin D in the body, it can affect the hair growth cycle. Low levels of vitamin D have been linked to various types of hair loss. These conditions involve different factors that disrupt the normal hair growth cycle, and vitamin D deficiency may contribute to their development.

However, more research is needed to determine if vitamin D supplements can effectively treat hair loss or should be recommended as a standard treatment.

Other Symptoms

• Bone loss: Low vitamin D levels could increase your risk of osteoporosis and broken bones. A severe shortage of vitamin D causes rickets and osteomalacia, which are soft, weak bones.
• Unexplained pain: Vitamin D deficiency can cause unexplained pain by affecting bones, muscles, and nerves. Low vitamin D levels weaken bones, lead to muscle weakness, and damage nerves, contributing to chronic pain.
• Psoriasis (inflammatory skin stuff): So, like, Vitamin D might have an effect on psoriasis by messing with the immune system and how skin cells grow. Lots of folks with psoriasis have low levels of vitamin D. I’m not totally sure how it works, but it might play a part in things like those thick, scaly plaques. Sometimes, treatments for psoriasis involve using vitamin D to help deal with the symptoms.

Sources of Vitamin D

Pfew, that was quite difficult, right? We don’t tell these things to make you feel anxious but to stress the importance of vitamin D intake. In the upcoming paragraphs, we’re going to tell you exactly how you can avoid all of these nasty things. And believe me, we’re going to keep it simple this time.

Sunlight Exposure

If you came this far, this is basic knowledge. The sun is a source of vitamin D for the body. Well, not really, because the body produces it with the influence of the sun. Vitamin D is made from cholesterol in your skin when it’s exposed to the sun. The sun’s ultraviolet rays (UVB) hit cholesterol in the skin cells, providing the energy for vitamin D synthesis to occur.

The best time to expose your skin to sunlight is during midday, in the summer. At noon, the sun is at the highest point in the sky, making the UVB the most intense. This means you have to expose your body for the least amount of time. This way you get your amount of vitamin D.

In the UK, 13 minutes of midday sunlight 3 times a week is enough. This maintains healthy levels of vitamin D for adults. Be careful with this tho: research has found that 30 minutes in the midday sun in Oslo, Norway is equivalent to 10.000-20.000 IU, which is 16-33X the necessary amount of vitamin D. An overdose of sunlight exposure is related to skin cancer.

The commonly recommended daily dose of vitamin D is 600 IU (15 mcg).

Generally speaking: the further you live from the equator, the more time you need to spend in the sun to get the necessary amount of vitamin D. In the same place in Norway, people cannot make vitamin D from the sunlight between October and March. In that case, supplementing vitamin D is almost your only option.

Supplements

With almost all things go: the nutrients come from your daily diet, not from supplements. Except for vitamin D. Vitamin D is found in a small number of foods, and also in a small concentration. If you want to substitute sunlight exposure with your diet, you’re probably cooked. Vitamin D can be found in small amounts in sources like fish, red meat, liver, egg yolks, and more. These will be discussed after the supplement section.

Vitamin D2 VS D3

With vitamin D, there are 2 forms available for supplementation: vitamin D3 and vitamin D2. Vitamin D2 comes from plant-based nutrition, such as mushrooms. Vitamin D3 comes from sunlight, fish, meat, eggs, and dairy. Vitamin D3 is essential for the absorption and utilization of calcium and phosphorus, which are vital for maintaining strong and healthy bones. Vitamin D3 supplementing is sufficient to meet your overall vitamin D needs. Basically, vitamin D3 is the only one your body is deficient in.

Besides the above-named effects, vitamin D has also a relation with testosterone levels. A Danish study in 2018 concluded that vitamin D supplementing had a positive effect on people with vitamin D deficiency. Testosterone levels rose by 3 nmol/liter to 13.4 nmol/liter in 12 months in another study.

To get an idea of what we’re talking about: 2 gummies of our #1. vitamin D supplements contain 50 mcg of vitamin D, whereas 100g of salmon contains around 10.9-14 mcg of vitamin D and 1 large egg contains around 1.1 to 1.6 mcg (micrograms) of vitamin D. See what we’re talking about?

Best Vitamin D Supplements

It’s clear why vitamin D supplementation is more effective than vitamin D intake via your daily nutrition. But with so many supplements on the market: which one do I choose? This blog is not focused on the best vitamin D supplements. We’ll quickfire the best ones we found on the market.

We’ll rank these based on the following factors:

• Third-party tested. All the supplements have been tested by third parties, indicating the companies’ confidence in their quality. A Certificate of Analysis (COA) from NSF, USP, BSCG, or ConsumerLab is an important indicator of quality.
• The amounts of vitamin D (MCG). That’s the thing we want, right? A lot of vitamin D per product. Be careful with your vitamin D intake tho: only use these products in winter or autumn, as the sun is your biggest source of vitamin D in the summer. Vitamin D toxicity is a rare, but potentially serious condition caused by an overload of supplements.
• Other vitamins. Other vitamins, such as ones that regulate vital metabolic functions, including growth, nerve function, and digestion, are also important. Vitamins C and B dissolve in water and are not stored by the body, whereas A, D, E, and K can be stored in fat.
• Preventing Proprietary Blends. Proprietary blends are a combination of multiple names in 1. They provide a mixture of ingredients that is unique to a particular manufacturer. Therefore, it lacks transparency, as it’s difficult to decide whether you’ve hit your daily goals

Let’s go.

Before we start, these are the upper limits of vitamin D you should consume, based on your age:

Ages	Upper Limit
Children 4-8 years	75 mcg (3,000 IU)
Children 9-18 years	100 mcg (4,000 IU)
Adults 19+ years	100 mcg (4,000 IU)
Pregnant and breastfeeding women	100 mcg (4,000 IU)

#1: The Vitamin Shoppe, Vitamin D3

The Vitamin Shoppe always brings out class products. Their vitamin D3 contains 50 mcg per serving size of 1 capsule. Remember that vitamin D3 is enough to reach your daily vitamin D goals.

Their product is as natural as it can get. No added gluten, dairy, sugar, soy, or wheat. So if you’re allergic to some of these things: don’t worry. Also, their product is preservative-free and free of artificial flavors & colors.

Their product is priced at $10, coming down to $0.10 per serving.

#2: Nordic Naturals, Vitamin D3

A bit less natural (in contradiction to its name), but the vitamin D3 from Nordic Naturals offers a lot of other benefits. Besides containing 25 mcg of vitamin D3 (or 1.000 IU) per serving size (3 capsules), it also contains vitamin E, olive oil (for the omega-3), and oleic acid (providing omega-9).

Besides containing a lot of vitamins, Nordic Natural is also a great source of healthy fats.

Their product is free of milk, preservative-free, and allergy-friendly.

Pricing? Their package is priced at $16.78, coming down to $0.14 per serving.

#3: PLNT, Vitamin D3

Sourced from algae, this vitamin D3 is naturally derived from algae, a popular supplement known for its lipids, vitamins, minerals, and essential fatty acids.

The PLNT vitamin is vegan, dairy-free, gluten-free, non-GMO, soy-free, and organic.

1 serving/tablet is 50 mcg, which is solid. The only thing we don’t like about this product is the amount of ingredients it has. These are all organic, so it’s not that big of a problem.

Pricing is on the higher side, with a package priced at $20. This comes down to $0.33 per serving.

#4: Solaray, Vitamin D3 + K2

For all my vegetarian brothers and sisters here: we got you. These vegcaps from Solaray contain both D3 and K2. Vitamin K2 plays a key role in calcium metabolism. This is helpful because every VegCap contains 110 mg of calcium.

Besides this, every capsule provides 125 mcg of vitamin D (!). We don’t know exactly why they’ve put so much vitamin D in it, as a normal human being should consume 100 mcg of vitamin D max. Consuming more than this may be harmful in the long run.

Therefore, it is not mandatory to take this supplement every day. Alternate days, or even 2 days apart, is also just fine.

The pricing is incredible with this one. 1 package of 60 VegCaps comes down to $16, which is $0.26 per serving. Keep in mind to cut your intake down to 1 capsule every 2 days for example.

Combining vitamins D and K enhances bone and cardiovascular health by improving calcium metabolism, as vitamin D aids calcium absorption and vitamin K ensures it is properly utilized. Studies suggest that taking both vitamins together is more effective. This is particularly true for postmenopausal women’s bone health. It may be beneficial for heart health as well.

#5: Life Extension, Vitamin D & K

The last one on this list is the vitamin D & K from Life Extension. It has added iodine, of which the health benefits are discussed in our previous blog. Besides this, it contains 125 mcg of vitamin D per serving size of 1 capsule, so it’s the same story as with the vitamin D from Solaray.

As stated before, it also contains vitamin K. Not just a little bit, but every K-vitamin is added to this supplement. This comes down to 2100 mcg of vitamin K in total. It includes 1000 mcg of K1, 1000 mcg of K2, and 100 mg of K2 (as trans-menaquinone-7).

We don’t like the amount of ingredients it has, as we strive for natural, basic products, but enfin.

1 package comes down to $19.80, which means $0.33 per serving of 1 supplement. As stated with the Solaray one: don’t use it every day, or don’t take 1 supplement as a whole.

When to Take Vitamin D Supplements?

To maximize the effectiveness of vitamin D supplements, it’s best to take them with a meal that contains fat. Vitamin D is fat-soluble and absorbs better with dietary fat. Foods like avocados, nuts, seeds, full-fat dairy products, and eggs can enhance absorption.

Although research on the best time of day to take vitamin D is limited, some studies suggest taking it in the morning might be more beneficial. This is especially true for avoiding potential sleep disturbances. Find a consistent time to take your supplement. Take it with breakfast or a nutritious snack. This will help ensure you meet your vitamin D needs. It will also support your overall health.

Vitamin D-Rich Foods

Prefer regular food over supplements? Normally, we would agree with you. But during winter times, it’s hard to reach your daily goal of 100mg of vitamin D just by nutrition. This section will be dedicated to foods that are rich in vitamin D. These foods are complementary to the vitamin D achieved from sunlight exposure.

Some of the best dietary sources of vitamin D include:

1. Fatty Fish:

• Salmon: One of the richest sources, wild-caught salmon can provide up to 14-16 mcg (570-640 IU) of vitamin D per 100 grams.
• Mackerel: Contains about 16.1 mcg (645 IU) per 100 grams.
• Tuna: Offers around 6.7 mcg (268 IU) per 100 grams when canned in water.

2. Fortified Foods:

• Fortified Milk: Typically contains about 1.3 mcg (52 IU) per cup (240 ml).
• Fortified Orange Juice: Provides approximately 2.5 mcg (100 IU) per cup (240 ml).
• Fortified Cereals: Varies by brand but generally contains around 2.5 mcg (100 IU) per serving.

3. Egg Yolks: One large egg yolk can provide around 1.1 mcg (44 IU) of vitamin D.

4. Cheese:

• Cheddar: Contains about 0.6 mcg (24 IU) per 100 grams.
• Other varieties also contribute smaller amounts but are still beneficial when included in a balanced diet.

5. Cod Liver Oil: An excellent source, providing about 34 mcg (1360 IU) per tablespoon (15 ml).

By regularly consuming these vitamin D-rich foods, you can better support your overall health, even during the darker months. Combining these dietary sources with the vitamin D your body synthesizes from sunlight exposure can help ensure you meet your daily requirements.

Treatment Options for Vitamin D Deficiency

Okay, but what if you’re in a deficiency already? What if you experience the symptoms listed above, and already consulted your doctor? While we always recommend to talk to a medical professional, this paragraph shows the natural ways to get to normal levels of vitamin D.

Increase Sunlight Exposure:

• Aim for 10-30 minutes of midday sunlight several times a week, depending on your skin type, age, and geographical location.
• Expose larger areas of your skin, such as arms and legs, to maximize vitamin D production.
• Be mindful of sunscreen use; while it protects against harmful UV rays, it can also reduce vitamin D synthesis. Short periods of sun exposure without sunscreen may be beneficial, but always avoid sunburn.

Consume Vitamin D-Rich Foods

• Fatty Fish: Include salmon, mackerel, sardines, and tuna in your diet. These fish are among the best sources of vitamin D.
• Egg Yolks: Eggs from chickens raised outside or fed vitamin D-enriched feed contain higher levels of the vitamin.
• Fortified Foods: Many dairy products, plant-based milk, orange juice, and cereals are fortified with vitamin D. Check food labels to identify these products.
• Mushrooms: Some mushrooms, like shiitake and maitake, naturally contain vitamin D, especially if they have been exposed to UV light.

Maintain A Healthy Weight

• Excess body fat can store vitamin D and alter its release into the bloodstream, making it less available for use. Maintaining a healthy weight through a balanced diet and regular exercise can improve vitamin D metabolism.
• Physical Activity:
• Regular physical activity, especially outdoor exercise, can help increase your exposure to sunlight. It can improve overall health and aid in the efficient use of vitamin D.

Consider Supplements:

• Vitamin D3 Supplements: These are often recommended. They are more effective at raising vitamin D levels in the blood compared to D2. Dosages can vary, so follow your healthcare provider’s advice on the appropriate amount.
• Combined Supplements: Sometimes, vitamin D is combined with calcium supplements, which can be beneficial for bone health.

Monitor Your Levels:

• Regular blood tests can help monitor your vitamin D levels and adjust supplementation or lifestyle changes as needed.

Always follow your healthcare provider’s guidance when addressing vitamin D deficiency. This ensures a safe and effective approach and is tailored to your specific health needs.

Conclusion

As summer approaches, it’s important to recognize the crucial role vitamin D plays in our overall health. The sun is our most natural and efficient source of this vital nutrient. This nutrient is often deficient during the darker, colder months. Vitamin D is not just important for maintaining a positive mood. Though it certainly helps alleviate winter blues and regulate mood. It also supports essential bodily functions.

With more lengthened sunny days ahead, here is your golden chance to amply accrue the supplies of this essential nutrient from its free sources:. Spending time outdoors, especially at noon, greatly increases the production of vitamin D in the human body. If you happen to live in places that do not get much sunlight or have any other limiting health conditions that limit sun exposure, then a vitamin D supplement is something worth considering. Understand that while food can add to your intake of vitamin D, most foods are not enough on their own.

Therefore, supplements, especially those with vitamin D3, are effective in ensuring sufficiency. Putting it all together, sensible sun exposure, a diet containing vitamin D, and appropriate supplementation will keep you healthy and minimize the risks associated with deficiency for a vibrant and energetic summer!