Vitamin D—a.k.a. the “sunshine” vitamin—can bolster your immune system, bone strength, and heart health.
Although your body makes it when you’re exposed to the sun, supplements are more dependable sources of this nutrient, especially if you have a significant vitamin D deficiency.
But which ones really work? Explore the best vitamin D supplement brands, analyzing their pros and cons, ingredients, dosage, cost, and user reviews.
Overall, our favorite is Akasha Naturals, thanks to its high dose of vitamin D and softgel capsules. However, you’ll find more options in our list that are suitable for every need.
Best Vitamin D Supplements in 2024
- Akasha Naturals Vitamin D - Best vitamin D supplement overall
- Natural Stacks Coconut Vitamin D3 - Most bioavailable supplement
- Mindbodygreen Vitamin D3 Potency+ - Best organic formula
- Ancient Nutrition Ancient Nutrients Vitamin D - Best vitamin D supplement for women
- Human Beanz Vitamin D3 Jelly Beans - Best vitamin D supplement for kids at heart
- New Chapter Fermented Vitamin D3 - Best vitamin D supplement for inflammation
- Garden of Life Vitamin Code Raw D3 - Best vitamin D supplement for men
- Life Extension Liquid Vitamin D3 - Most affordable vitamin D supplement
- Hi-Tech Pharmaceuticals Vitamin D3 - Most innovative vitamin D supplement
What Are Vitamin D Supplements?
Vitamin D—also known as calciferol—is a fat-soluble vitamin that plays a big role in your body. Unlike other vitamins, vitamin D works like a hormone; every cell in your body has a receptor for it.
Forms of Vitamin D Supplements
There are several ways to get vitamin D as a supplement, such as:
- Tablets
- Capsules
- Gummies
- Liquid form
- Spray form
Which one is the best for you depends on your goals and preferences.
1. Akasha Naturals Vitamin D - Best Vitamin D Supplement Overall
Pros
- A large dose of 5,000 IU
- Softgel capsules may be easier to break down
- Costs only around $0.27 per dose
Cons
- Contains gelatin
Overview
We picked Akasha Naturals as the #1 best vitamin D supplement because it packs a generous dose of this nutrient while having no harmful fillers.
Key Ingredients
Akasha Naturals’ vitamin D supplement contains nothing but vitamin D3 in a softgel capsule.
Research shows that this dose per capsule may improve your health. For example, one paper showed that taekwondo athletes with low vitamin D levels had much lower respiratory tract infection symptoms after supplementing with 5,000 IU for one month [1].
Vitamin D3 may also enhance your cognitive function. A paper on vitamin D3 in Alzheimer’s disease shows that, over one year, participants’ vocabulary, math skills, IQ, and other areas improved a lot [2].
Dosage
Take a single capsule a day. Each serving contains 5,000 IU of vitamin D (or 125 mcg).
Pricing
While a one-time purchase costs $33.25, a subscription saves 15% at just $28.26. One bottle has 120 doses (or enough for almost four months).
User Reviews
While it’s challenging to find reviews for this product on Reddit or Trustpilot, many customers praise the health benefits of Akasha Naturals—like immune support, weight loss, and greater energy—on its official website.
>>Check the best prices for Akasha Naturals’ Vitamin D here
2. Natural Stacks Coconut Vitamin D3 - Most Bioavailable Supplement
Pros
- Includes organic coconut oil to boost absorption
- Fantastic value for money at less than $10 per month
- 100% money-back guarantee
Cons
- May not be fitting if you’re allergic to tree nuts
Overview
Natural Stacks’ Coconut Vitamin D3 could be the best vitamin D supplement when it comes to bioavailability—meaning your body can easily absorb and use it. Plus, it only costs around $0.33 cents per dose.
Key Ingredients
Natural Stacks combines vitamin D3 with coconut oil to make it more absorbable, which potentially leads to better results.
A clinical study comparing vitamin D3 in olive oil, coconut oil, and a plain supplement suggests that only the coconut oil increased the body’s absorption [3].
Dosage
Take one capsule every day, preferably with food.
Pricing
You’ll only be paying $9.95 for a one-time purchase of a single bottle. Even better, the price will be lowered to just $7.96 for one month’s supply when you sign up for a subscription.
User Reviews
Natural Stacks got many positive feedback from customers, including a Trustpilot reviewer who thinks that the company’s products rock while the support is spot on [4]. On the other hand, a few Trustpilot users are not that happy with the customer service [5].
>>Check the best prices for Natural Stacks Coconut Vitamin D3 here
3. Mindbodygreen Vitamin D3 Potency+ - Best Organic Formula
Pros
- USDA certified organic
- Combines vitamin D3 with three plant-based oils
- If you’re eligible, you can pay using FSA and HSA funds
Cons
- Not a good match for vegans
Overview
Mindbodygreen is the best vitamin D supplement with organic ingredients, starting from the algal oil and moving up to the three organic oils that fight inflammation.
Key Ingredients
MindBodyGreen’s vitamin D3 supplement contains algal-derived vitamin D3, which is carried by flax, olive, and avocado oils.
A lab study shows that vitamin D3 and olive oil greatly improved bone density while reducing inflammation and oxidative stress [6].
Dosage
Each daily dose (or one gelcap) contains 5,000 IU of vitamin D3.
Pricing
While a one-time purchase costs $30 monthly, a 30-day subscription is priced at $25, and a 180-day subscription works out at $17 a month.
User Reviews
Mindbodygreen has received a lot of positive feedback from customers. For example, a Reddit user on r/betabattle likes the vitamin supplements because they help her maintain her well-being in her 30s [7]. Nevertheless, she also says that these products come at a higher price point.
>>Check the best prices for Mindbodygreen Vitamin D3 Potency+ here
4. Ancient Nutrition Ancient Nutrients Vitamin D - Best Vitamin D Supplement for Women
Pros
- Probiotic-fermented vitamin D3
- Added vitamin K2 for better bone and cardiovascular health
- Adaptogens for improved energy and fitness
Cons
- It contains beef, so vegetarians can’t take it
Overview
Since it’s formulated to strengthen your bones, Ancient Nutrition’s offering can be counted as the best vitamin D supplement for women.
Key Ingredients
Ancient Nutrients’s vitamin D combines vitamin D3 and K2, which may support your bone health (especially if you’re a woman). A study on postmenopausal ladies with osteoporosis reveals that this combination was more effective in improving bone mineral density than calcium supplements or either vitamin D3 or K2 alone [8].
It also contains the Ancient Nutrients TCM Blend. This includes beef liver, bone broth, organic lion’s mane, organic schisandra, and organic reishi extracts.
Dosage
Take one pill of this female-friendly supplement every day; each bottle contains 60 capsules.
Pricing
A one-time purchase costs $29.95. On the other hand, a subscription gives you the chance to save 20% on your first month and then 15% in the following months. So, you only have to pay $25.46 on your first order.
User Reviews
A good number of users have great things to say about Ancient Nutrition. In r/Supplements, a Redditor says she takes Ancient Nutrition because of the great levels of vitamin D, plus other nutrients [9]. Another Reddit user shares in a different r/Supplements thread that he’s still deciding whether to try Ancient Nutrition or another brand [10].
>>Check the best prices for Ancient Nutrition Ancient Nutrients Vitamin D here
5. Human Beanz Vitamin D3 Jelly Beans - Best Vitamin D Supplement for Kids at Heart
Pros
- Convenient candy form with a natural strawberry flavor
- One of the best vegan vitamin D supplements that’s gluten-free and nut-free
- 2000 IU of vitamin D3 makes customizing your dose easier
Cons
- Contains sugar
Overview
Human Beanz showcases these vitamin D supplements in the form of an easy-to-take and enjoyable candy. Are you nostalgic about the gummies you popped when you were young? These could be the best vitamin D supplement for kids at heart like you. In addition, the product itself states that the supplement might be safe for children over the age of 2.
Key Ingredients
Human Beanz’s Vitamin D3 Jelly Bean Gummies come with 2,000 IU per serving of four gummies (or 500IU per bean).
The Endocrine Society recommends a vitamin D intake of 600 IU for people below 70 years old and 800 IU for anyone older [11].
The Centers for Disease Control and Prevention (CDC) also recommends 600 IU of vitamin D for children between the ages of 1 and 2.
Dosage
You can chew four jelly bean gummies every day, eating them all at once or splitting your dose throughout the day.
Pricing
Each jar costs $13.99 for 30 doses or one month’s supply.
User Reviews
Some Amazon buyers think that Human Beanz’ gummies taste really good [12], which makes them a lot easier to remember to take [13]. However, a few Amazon reviewers feel the gummies are too sweet [14].
>>Check the best prices for Human Beanz Vitamin D3 Jelly Beans here
6. New Chapter Fermented Vitamin D3 - Best Vitamin D Supplement for Inflammation
Pros
- Turmeric may bring down swelling
- Reishi can strengthen your immunity
- Includes organic ingredients
Cons
- Contains soy, which some folks might be allergic to
Overview
If your joints or gut are inflamed, New Chapter’s fermented formula might be the best vitamin D supplement for you.
Key Ingredients
New Chapter’s key ingredients are vitamin D3 at a dose of 2,000 IU, plus turmeric and reishi.
Turmeric could reduce pain and swelling caused by arthritis, so you can move around better [15].
As for reishi, this medicinal mushroom may bring down inflammation in your colon. It encourages your body to create more fatty acids by gut bacteria. Better yet, it strengthens the gut barrier as well [16].
Dosage
Take one tablet of this supplement every day.
Pricing
Each bottle costs $32.99 for 90 tablets (or almost three months’ supply).
User Reviews
Some customers recommend New Chapter, including a Redditor on R/AskMen who likes the brand’s supplements (including vitamin D). According to him, the vitamins are fermented, so they are recognized by your body as food and are more easily absorbed [17]. In r/Supplements, one Reddit user feels the brand is no longer as dedicated to its mission as it used to be [18].
>>Check the best prices for New Chapter Fermented Vitamin D3 here
7. Garden of Life Vitamin Code Raw D3 - Best Vitamin D Supplement for Men
Pros
- Raw, organic fruit and vegetable blend
- Features digestive enzymes
- Just $0.22 per daily dose
Cons
- Low doses of natural extracts aren’t likely to have a big impact
Overview
Are you a guy who doesn’t eat much veggies or fruits? The antioxidant-packed Garden of Life may be the best vitamin D supplement for men like you.
Key Ingredients
Each Garden of Life capsule contains 2,000 IU of vitamin D3; this may be a better dose than 5,000 IU for people with smaller body sizes.
It also packs 22 organic fruit and vegetable extracts. These are rich in polyphenols—plant compounds with antioxidant and anti-inflammatory effects [19].
This supplement could come in handy for men, as guys usually eat less fruit and vegetables [20].
Dosage
Take one pill every day with meals, or you can empty the capsule into raw juice or water.
Pricing
One bottle of 120 capsules—or almost four months’ supply—costs $27.29.
User Reviews
Certain buyers recommend Garden of Life Vitamin Code Raw D3. One of them is a Reddit user from r/WholeFoodsPlantBased who likes how you can undo the capsules and put them in food [21]. Nonetheless, another Reddit participant in the same thread prefers another brand that offers vitamin drops.
>>Check the best prices for Garden of Life Vitamin Code Raw D3 here
8. Life Extension Liquid Vitamin D3 - Most Affordable Vitamin D Supplement
Pros
- Just $0.02 per serving
- Carried in MCT oil (from coconuts) for better absorption
- Supports your brain and bone health
Cons
- Not all folks like the texture of oil-based liquid supplements
Overview
Among the best vitamin D supplements in our roundup, the Liquid Vitamin D3 by Life Extension is hands down the most budget-friendly of the bunch. It’s only $0.02 per serving!
Key Ingredients
Life Extension’s supplement is made from vitamin D3 in medium-chain triglyceride (MCT) oil from coconuts. In the coconut oil vs. olive oil face-off, coconut oil may boost the absorption of vitamin D better [3]. Additionally, liquid supplements can be absorbed faster than tablets or capsules.
Dosage
Take one drop once or twice daily, along with some food.
Pricing
For just $21, you’ll receive a bottle with around 850 doses. This is enough for over two years, or it could last just over one year if you need to double the dose.
User Reviews
Several customers consider Life Extension to be a great brand for vitamin D supplements, such as two Redditors who recommend it on r/Supplements [22]. Other Reddit users on the same thread also mention other brands, though.
>>Check the best prices for Life Extension Liquid Vitamin D3 here
9. Hi-Tech Pharmaceuticals Vitamin D3 - Most Innovative Vitamin D Supplement
Pros
- Includes phospholipids to enhance absorption
- 100 dosages in just one bottle
- Discounts on larger orders
Cons
- Some folks find it hard to swallow tablets
Overview
If you’re an avant garde user, Hi-Tech Pharmaceuticals’ offering is the best vitamin D supplement that features cutting-edge Cyclosome technology for enhanced bioavailability.
Key Ingredients
Hi-Tech Pharmaceuticals showcases phospholipids: the same type of fatty acid that makes up your cell membranes. Studies show that phosphatidylcholine can boost the absorption of vitamin D more than coconut or olive oil alone [23].
Dosage
Take one tablet a day, or two if you’re very deficient in this nutrient.
Pricing
One bottle of 100 tablets costs $19.95. If you buy two or three bottles, these will give you a 10% or 15% discount, respectively.
User Reviews
Some customers gave a virtual nod of approval to Hi-Tech Pharmaceuticals Vitamin D3. One Redditor on r/Supplements says the brand’s supplements are fine, if only not a little overpriced [24]. In this very same thread, a different Reddit user is still wondering if the company’s products are safe and effective but is open to listening to feedback from others.
>>Check the best prices for Hi-Tech Pharmaceuticals Vitamin D3 here
Natural Sources of Vitamin D
There are other sources of vitamin D that you can tap in your everyday lifestyle, including:
Sunlight Exposure
Your body naturally produces vitamin D3 during sun exposure. However, it’s currently not recommended to spend too much time in the sun because of the thinning ozone layer [25].
Food Sources Rich in Vitamin D
Natural sources of vitamin D include fatty fish (like trout, salmon, and mackerel), fish liver oils, beef liver, cheese, and egg yolks, and some mushrooms [26].
Fortified Foods
Most of the vitamin D in American diets comes from fortified foods such as milk, cereals, yogurt, and margarine [26]. Another alternative is the best calcium and vitamin D supplements.
Vitamin D in Animal Products
Almost all natural sources of vitamin D are animal products, including fish. This is why we included one of the best vegan vitamin D supplements in our review for the sake of those with dietary restrictions.
Factors To Consider When Choosing Vitamin D Supplements
Keep these things in mind when picking the best vitamin D supplement for you.
- Dosage requirements: The dosages of the active ingredients must be high enough to be potentially effective, based on clinical research.
- Bioavailability and absorption: The supplement should come in a form that allows your body to easily absorb and use the vitamin D.
- Ingredients and additives: Go for brands that contain active ingredients that are scientifically supported to bolster your health; the supplements ought to have zero or minimal additives, too.
- Allergens and dietary restrictions: Check the label first! Make sure you’re not sensitive to any of the ingredients in the formula to avoid allergic reactions.
- Price and value for money: Don’t just look for the cheapest products; be sure that you’re getting bang for your buck—whether in terms of dosages or health benefits.
Benefits of Vitamin D Supplements
The best vitamin D supplements may support bone, immune, brain, heart, and muscle health.
- Bone health and osteoporosis prevention: You need vitamin D for your gut to absorb calcium, which keeps your bones healthy and fights osteoporosis.
- Immune system support: Vitamin D improves your body’s immune responses. It reduces inflammatory signals to lower your risk of diseases such as multiple sclerosis [27].
- Mood and mental health: Vitamin D3 can support mental health in both adults and children. For example, it may alleviate emotional problems and improve self-regulation in children with ADHD [28].
- Weight management: Wondering, “What vitamins are good for losing belly fat?” Well, vitamin D may assist you in overcoming insulin resistance—which could hinder your efforts in burning body fat and shedding extra pounds.
- Heart health: Sufficient vitamin D levels could also help prevent cardiovascular problems—such angina, coronary artery disease, and heart attack [29].
- Muscle function: What’s more, vitamin D3 can boost muscle growth and maintenance. A study shows that athletes taking vitamin D3 (but not vitamin D2) may notice greater strength by up to 18% [30].
- Hair maintenance: Vitamin D deficiency might cause hair loss. Thankfully, getting enough of this nutrient could help prevent your hair from shedding and thinning too early.
>>Check the best prices for Akasha Naturals Vitamin D here
Potential Side Effects and Precautions
Vitamin D supplements are generally considered safe for most healthy users, like the best weight loss supplements.
Still, there’s a small possibility it might cause signs of side effects in some users, such as:
- Hypercalcemia (or too much calcium in your blood [31]
- Digestive issues [31]
- Kidney stones
- Interactions with medications
- Allergic reactions
FAQs on the Best Vitamin D Supplements
Check out the top questions many customers ask about the best vitamin D supplement.
Which Vitamin D Supplement Is Most Effective?
The most effective vitamin D supplement for each user may vary based on their individual needs and body chemistry.
Which Vitamin D Should I Take Daily?
While the recommended daily intake is around 400-500 IU, you may require the 5,000 IU doses seen in some products we’ve reviewed to combat winter deficiencies.
What Is the Best Form of Vitamin D Supplement To Take?
It really depends on what form of vitamin D supplement you prefer. For example, you might be more comfortable taking a capsule, liquid, or gummy.
How Long Does It Take for Vitamin D Supplements To Work?
Usually, you might notice the benefits of vitamin D in less than one month. Yet, the exact time frame may be different for every user.
When Is the Best Time To Take Vitamin D Supplement?
As vitamin D is fat soluble, we recommend taking it during meal times (especially if you eat fatty foods) to boost absorption.
When Is the Best Vitamin D Supplement for Men?
The best vitamin D supplement for men we found is the antioxidant-rich Garden of Life Vitamin Code Raw D3.
When Is the Best Vitamin D Supplement for Women?
The best vitamin D supplement for women on our list is Ancient Nutrients Vitamin D by Ancient Nutrition, as it combines vitamin D3 with K2. Some of the best menopause supplements also come with vitamin D and other nutrients that support women’s health.
Final Word on the Best Vitamin D Supplement
In a nutshell, you need vitamin D to keep your heart, muscles, bones, and immune system healthy. Taking a supplement can ensure you get sufficient amounts that your body needs.
Overall, we picked Akasha Naturals as the best vitamin D supplement since it packs a powerful dose in a user-friendly softgel capsule. Of course, you can choose any of the brands in our list since they have their own health benefits as well.
Stay healthy!
>>Check the best prices for Akasha Naturals Vitamin D here
References
- Jung, Hyun Chul et al. “Vitamin D₃ Supplementation Reduces the Symptoms of Upper Respiratory Tract Infection during Winter Training in Vitamin D-Insufficient Taekwondo Athletes: A Randomized Controlled Trial.” International journal of environmental research and public health vol. 15,9 2003. 14 Sep. 2018, doi:10.3390/ijerph15092003
- Jia, Jingya et al. “Effects of vitamin D supplementation on cognitive function and blood Aβ-related biomarkers in older adults with Alzheimer's disease: a randomised, double-blind, placebo-controlled trial.” Journal of neurology, neurosurgery, and psychiatry vol. 90,12 (2019): 1347-1352. doi:10.1136/jnnp-2018-320199
- McCourt, Aislinn F et al. “Serum 25-hydroxyvitamin D response to vitamin D supplementation using different lipid delivery systems in middle-aged and older adults: a randomised controlled trial.” The British journal of nutrition vol. 130,9 (2023): 1548-1557. doi:10.1017/S0007114523000636
- Faith Darjia gave Natural Stacks 5 stars. Check out the full review... (2023, October 25). Trustpilot; Trustpilot. https://www.trustpilot.com/reviews/6539548f514940f02aab87a5
- Natural Stacks is rated “Average” with 3 / 5 on Trustpilot. (2024, July 12). Trustpilot; Trustpilot. https://www.trustpilot.com/review/naturalstacks.com
- Tagliaferri, Camille et al. “Olive oil and vitamin D synergistically prevent bone loss in mice.” PloS one vol. 9,12 e115817. 31 Dec. 2014, doi:10.1371/journal.pone.0115817
- R/Betabattle on Reddit: Best Multivitamin for Women R/Supplements Reddit, www.reddit.com/r/betabattle/comments/197vwbn/best_multivitamin_for_women_rsupplements_reddit/.
- Iwamoto, J et al. “Effect of combined administration of vitamin D3 and vitamin K2 on bone mineral density of the lumbar spine in postmenopausal women with osteoporosis.” Journal of orthopaedic science : official journal of the Japanese Orthopaedic Association vol. 5,6 (2000): 546-51. doi:10.1007/s007760070003
- R/Supplements on Reddit: If You Could Only Have 3 Supplements What Would They Be?, www.reddit.com/r/Supplements/comments/138z09f/if_you_could_only_have_3_supplements_what_would/.
- R/Supplements - What Do You Prefer Ancient Nutrition or Left Coast Performance?, www.reddit.com/r/Supplements/comments/ms3h5d/what_do_you_prefer_ancient_nutrition_or_left/.
- Holick, Michael F et al. “Evaluation, treatment, and prevention of vitamin D deficiency: an Endocrine Society clinical practice guideline.” The Journal of clinical endocrinology and metabolism vol. 96,7 (2011): 1911-30. doi:10.1210/jc.2011-0385
- Amazon.com. (2014). Amazon.com. https://www.amazon.com/gp/customer-reviews/R3KYM5I8TA2FM/ref=cm_cr_dp_d_rvw_ttl?ie=UTF8&ASIN=B0BQ7H5B74
- Check out this Amazon review of Human Beanz Vitamin D3 Jelly Bean Gummies for Adults, Immunity Support, 2000 IU Vitamin D, Nutritional Vegetarian Supplements, 120 Strawberry Blast Jelly Beans, Kosher. (2024). Amazon.com. https://www.amazon.com/gp/customer-reviews/RQ87AZNYOB0N7/ref=cm_cr_dp_d_rvw_ttl?ie=UTF8&ASIN=B0BQ7H5B74
- Amazon.com. (2014). Amazon.com. https://www.amazon.com/gp/customer-reviews/R1GTBBD55KENGH/ref=cm_cr_arp_d_rvw_ttl?ie=UTF8&ASIN=B0BQ7H5B74
- Zeng, Liuting et al. “Efficacy and Safety of Curcumin and Curcuma longa Extract in the Treatment of Arthritis: A Systematic Review and Meta-Analysis of Randomized Controlled Trial.” Frontiers in immunology vol. 13 891822. 22 Jul. 2022, doi:10.3389/fimmu.2022.891822
- Guo, Cuiling et al. “Ganoderma lucidum polysaccharide modulates gut microbiota and immune cell function to inhibit inflammation and tumorigenesis in colon.” Carbohydrate polymers vol. 267 (2021): 118231. doi:10.1016/j.carbpol.2021.118231
- R/Askmen on Reddit: What Vitamin/Supplements Do You Recommend for a 27M Bachelor That Does Not Eat Great?, www.reddit.com/r/AskMen/comments/1bmbtai/what_vitaminsupplements_do_you_recommend_for_a/.
- R/Supplements on Reddit: Is New Chapter’s Multi Good?, www.reddit.com/r/Supplements/comments/wtafq7/is_new_chapters_multi_good/.
- Bowtell, Joanna, and Vincent Kelly. “Fruit-Derived Polyphenol Supplementation for Athlete Recovery and Performance.” Sports medicine (Auckland, N.Z.) vol. 49,Suppl 1 (2019): 3-23. doi:10.1007/s40279-018-0998-x
- Howard Wilsher, Stephanie et al. “"That is an Awful Lot of Fruit and Veg to Be Eating". Focus Group Study on Motivations for the Consumption of 5 a Day in British Young Men.” Nutrients vol. 11,8 1893. 14 Aug. 2019, doi:10.3390/nu11081893
- R/Wholefoodsplantbased on Reddit: Vitamin D Supplement Recommendations, www.reddit.com/r/WholeFoodsPlantBased/comments/sx0ne5/vitamin_d_supplement_recommendations/.
- R/Supplements on Reddit: What Do You Recommend Great Brands for Vitamin D3 with K2?, www.reddit.com/r/Supplements/comments/1dl9kqg/what_do_you_recommend_great_brands_for_vitamin_d3/. Accessed 15 Aug. 2024.
- Mulrooney, Steven L et al. “Enhancing the bioaccessibility of vitamin D using mixed micelles - An in vitro study.” Food chemistry vol. 395 (2022): 133634. doi:10.1016/j.foodchem.2022.133634
- R/Supplements on Reddit: Can Anyone Give Me Some Experiences with Hi-Tech Pharmaceuticals?, www.reddit.com/r/Supplements/comments/r1daqa/can_anyone_give_me_some_experiences_with_hitech/.
- Barnes, Paul W., et al. “Ozone Depletion, Ultraviolet Radiation, Climate Change and Prospects for a Sustainable Future.” Nature Sustainability, vol. 2, no. 7, 24 June 2019, pp. 569–579, www.nature.com/articles/s41893-019-0314-2, https://doi.org/10.1038/s41893-019-0314-2.
- National Institutes of Health. “Vitamin D.” Nih.gov, 2017, ods.od.nih.gov/factsheets/VitaminD-Consumer/.
- Aranow, Cynthia. “Vitamin D and the immune system.” Journal of investigative medicine : the official publication of the American Federation for Clinical Research vol. 59,6 (2011): 881-6. doi:10.2310/JIM.0b013e31821b8755
- Hemamy, Mostafa et al. “The effect of vitamin D and magnesium supplementation on the mental health status of attention-deficit hyperactive children: a randomized controlled trial.” BMC pediatrics vol. 21,1 178. 17 Apr. 2021, doi:10.1186/s12887-021-02631-1
- Cosentino, Nicola et al. “Vitamin D and Cardiovascular Disease: Current Evidence and Future Perspectives.” Nutrients vol. 13,10 3603. 14 Oct. 2021, doi:10.3390/nu13103603
- Chiang, Chien-Ming et al. “Effects of Vitamin D Supplementation on Muscle Strength in Athletes: A Systematic Review.” Journal of strength and conditioning research vol. 31,2 (2017): 566-574. doi:10.1519/JSC.0000000000001518
- Asif, Anum, and Nauman Farooq. “Vitamin D Toxicity.” PubMed, StatPearls Publishing, 2021, www.ncbi.nlm.nih.gov/books/NBK557876/.