Supplements Vitamins & Minerals The Benefits of Getting Enough Vitamin D3 Why the sunshine vitamin is important By Yvelette Stines Yvelette Stines LinkedIn Yvelette Stines, MS, MEd, is an author, writer, and communications specialist specializing in health and wellness. Learn about our editorial process Updated on December 11, 2021 Medically reviewed Verywell Health articles are reviewed by board-certified physicians and healthcare professionals. These medical reviewers confirm the content is thorough and accurate, reflecting the latest evidence-based research. Content is reviewed before publication and upon substantial updates. Learn more. by Meredith Bull, ND Medically reviewed by Meredith Bull, ND Facebook LinkedIn Meredith Bull, ND, is a licensed naturopathic doctor with a private practice in Los Angeles, California. Learn about our Medical Expert Board Print Table of Contents View All Table of Contents How It Works Health Benefits Sources Deficiency Risks Frequently Asked Questions Vitamin D is important for overall health. You get it from the sun, foods you eat, or supplements. It comes in two main forms: D2 and D3. If you have too little, you may problems with your bones, muscles, immune system, and mood. You could also have more inflammation and pain. This article looks at vitamin D2 versus D3, the many benefits of vitamin D3, and how you can safely get more vitamin D into your diet. Olga Shumitskaya / Getty Images How Vitamin D Works Vitamin D helps control how much calcium and phosphate you absorb from food. Calcium is essential for bone health. Phosphate is needed for healthy bones, teeth, muscles, nerves, and basic bodily functions. Vitamin D comes in two forms: Vitamin D2 (ergocalciferol) is naturally found in some plants. Vitamin D3 (cholecalciferol) is naturally found in animals and is produced by the skin when it’s exposed to sunlight. You can meet your vitamin D needs with either form. But healthcare providers generally suggest D3 supplements. That's because it: Raises your overall vitamin D level more than D2Lasts longer in the body than D2 Recap Vitamin D helps regulate calcium and phosphate absorption in food. Calcium and phosphate are essential for many important functions. For supplements, D3 is considered better than D2. Health Benefits Vitamin D3 offers many health benefits. It: Strengthens bones and muscles Boosts immunityImproves moodReduces inflammationImproves heart function Bones Vitamin D works with calcium to support your bones. If you're low on vitamin D, your body can't get calcium from food. So it steals it from your bones. This leads to: Weaker bones Fractures Osteoporosis Getting more D3 from foods is helpful for improving peak bone density. That's the maximum amount of bone tissue you reach during adulthood. The better your bone density, the less likely you are to develop diseases (like osteoporosis) that weaken bones. Muscles Vitamin D appears to help you build stronger muscles. Studies suggest a link between muscle strength and high vitamin D levels. Researchers found people with more vitamin D had: Leaner bodiesMore muscle massBetter muscle function Recap Vitamin D is important for bone and muscle strength. It increases bone density and muscle mass. Low vitamin D puts you at risk for osteoporosis and other problems tied to weak bones. Immunity Vitamin D may help your immune system fight viruses and bacterial infections. Research suggests it helps you stave off: Acute respiratory infections Pneumonia Possibly, COVID-19 COVID-19 Risk Low vitamin D may put you at higher risk of catching COVID-19 and having severe symptoms. More research is needed to say for sure. Mood Low vitamin D levels may be linked to clinical depression. It's not clear why, though. It may be that: Low vitamin D causes depression Or depression behaviors (e.g., poor eating habits, less time outside) cause low vitamin D Evidence suggests raising vitamin D levels helps with depression symptoms. It may have a role in the depression treatment regimen. Larger studies are needed to understand the connection. Understanding Vitamin D Deficiency Recap Vitamin D may help your immune system fight off some illnesses, including COVID-19. It may also help alleviate depression symptoms. Anti-Inflammatory Effects Vitamin D may affect medical conditions caused by inflammation. Low vitamin D may increase your odds of having: Allergies Asthma Eczema Atopy (a genetic tendency to develop allergies) Studies have suggested taking vitamin D supplements during pregnancy makes babies less likely to have asthma. Always talk to your doctor before taking any supplements during pregnancy. Heart Health Research suggests a lack of vitamin D may increase your chances of: Heart diseaseStrokeBlood pressureHeart attacks D3 seems to reduce the risk of heart failure. It's believed to improve heart function in people with weak heart muscles. Again, more research is needed. Recap Low vitamin D may lead to inflammatory diseases such as allergies and asthma. It may also increase your odds of heart disease and stroke. Sources of D3 The U.S. Food and Drug Administration (FDA) vitamin D recommendations are: 600 IU (international units) for adults up to age 70800 IU per day for adults over 70 Most people can handle a maximum daily intake of 4,000 IU. You can increase your vitamin D levels by: Taking supplementsGetting more sunlightEating more foods with a lot of D3 It's hard to get enough D3 through diet alone. Eating more of the foods below can help. FOOD IU SERVING % RDA* Beef liver 42 3 oz. 5% Butter 9 1 Tbsp. 1% Cereal 80 40 grams 10% Cheese 12 1 oz. 2% Cod liver oil 1,360 1 Tbsp. 170% Egg yolks 44 1 yolk 6% Fresh salmon 570 3 oz. 71% Halibut 384 .5 fillet 48% Mackerel 360 .5 fillet 45% Milk, fortified 120 1 cup 15% Sardines 46 2 fish 6% Trout 645 3 oz. 81% Tuna 40 3 oz. 5% *Based on 800 IU per day. If you're a vegetarian or vegan, it's harder to get enough D3 from food. Supplements may be more important for you. You can also boost your vitamin D with foods that contain D2. FOOD IU SERVING %RDA* Almond, oat, or soy milk (fortified) 100-144 1 cup 13%-18% Mushrooms (portabella) 4 .5 cup 1% *Based on 800 IU per day. Supplements Supplements are the easiest way to get enough vitamin D3 every day. Studies suggest they boost D3 just as well as sunlight and food. Talk to your doctor about the benefits and best dosage for you before you start taking supplements. Be sure you're taking a high-quality product. The FDA doesn't oversee supplements. To find trusted brands, look for "USP Verified" on the label. That means the U.S. Pharmacopeial Convention (a nonprofit scientific organization) has verified that: Ingredients and potencies listed on the label are accurateThe product doesn't contain harmful levels of contaminantsYour body can absorb the supplementThe makers followed FDA guidelines and procedures Sunlight It may seem odd that sunlight can give you vitamin D. It doesn't do this directly. But it starts a chain reaction. Ultraviolet B rays from the sun hit your skin.They activate special vitamin-D receptor cell. That triggers a chemical reaction that makes your cells produce vitamin D3. Getting a little sunlight every day can help you maintain your D3 levels. But it's not the safest or most reliable way to stay healthy. If you don’t get much sun, use sunscreen regularly, or have darker skin, you likely won’t meet your vitamin D needs from the sun. One concern is the risk of cancer from sunlight. Some experts recommend 10 to 15 minutes of unprotected exposure a few times a week to help with vitamin D levels. But the Centers for Disease Control and Prevention (CDC) and other medical authorities say there's no safe way to get vitamin D from the sun without increasing your skin cancer risk. The second problem is that it's hard to rely on sunlight. And you can't measure how much vitamin D you're making from the sun. It's easier to keep track of the vitamin D in foods or supplements. Recap The recommended day amount of vitamin D is 600 IU for adults under 70 and 800 IU for those over 70. Foods with high amounts include many kinds of fish and fortified milk and cereal.Supplements are the most reliable way to maintain vitamin D levels.Sunlight increases vitamin D production in your body. But it's impossible to know how much it contributes. D3 Deficiency Research shows more than a billion people worldwide have a vitamin D deficiency. Symptoms include: Muscle weakness and achesWeak bonesFatigueInflammationHair loss The deficiency may lead to many health conditions, such as: DepressionHypertension (high blood pressure)ArthritisEczema A simple blood test can check your vitamin D levels. Your healthcare provider can order this as part of a regular check-up. Checking Levels The U.S. Preventive Services Task Force (USPSTF) doesn't recommend routine vitamin D screening in adults without related symptoms. If you suspect a vitamin D deficiency, ask your healthcare provider to test your levels. Risks Vitamin D3 is generally safe. But it can have toxic effects if you take too much. Excess Calcium Too much vitamin D can make you absorb excessive amounts of calcium. That can lead to a condition called hypercalcemia, which may: Weaken bonesInterfere with your brain and heartCause kidney stones Vitamin D3 Toxicity Some symptoms of vitamin D toxicity include: NauseaVomitingMuscle weaknessMood changesPainConfusionLoss of appetiteDehydrationExcessive urinationExcessive thirst Extremely high vitamin D3 levels can lead to: Kidney failureIrregular heartbeatDeath Toxicity problems are caused almost exclusively by supplements. It's hard to take in that much from food. And your body doesn't produce that much vitamin D from sunlight. Summary Vitamin D helps you absorb calcium and phosphate from food. D3 is more efficient than D2. You get vitamin D from food, supplements, and sunshine. Vitamin D is important for bone and muscle strength and immune function. It may help prevent depression, inflammatory disease, and heart disorders. Adults under 70 should get 600 IU a day. Older adults should get 800 IU. Supplements are the most reliable way to get enough vitamin D. Taking too much can have toxic effects. Have your healthcare provider test your levels before starting a supplement. A Word From Verywell If you have health conditions that could be tied to vitamin D, bring it up with your healthcare provider. It's easy to boost levels with supplements. And that could mean feeling a lot better and being healthier down the road. Frequently Asked Questions What is the difference between vitamin D and vitamin D3? Vitamin D3 is a form of vitamin D. It's called cholecalciferol. Your body takes the D3 from animal products like seafood, liver, and eggs and converts it into a usable form. When should I take vitamin D3? Vitamin D3 is a fat-soluble vitamin. That means taking it with fat helps it absorb better. It doesn't matter what time of day you take it. But you should eat fat-containing food at the same time. Learn More: What Is a Fat Soluble Vitamin? Is it okay to take vitamin D3 every day? Yes, you can take vitamin D3 daily. Talk to your doctor about the right dosage and be sure you don't take too much. Learn More: What to Know About Vitamin D Toxicity Does vitamin D3 give you energy? A lack of vitamin D can cause you to feel lethargic. So if you're deficient, taking D3 supplements could, over time, help you feel more energetic. However, D3 supplements don't provide an immediate energy boost. They won't reduce fatigue unless you have a deficiency. Learn More: Vitamin D Deficiency and Headaches Was this page helpful? Thanks for your feedback! Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life. Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit 16 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Hernigou P, Sitbon J, Dubory A, Auregan JC. Vitamin D history part III: the "modern times"-new questions for orthopaedic practice: deficiency, cell therapy, osteomalacia, fractures, supplementation, infections. Int Orthop. 2019;43(7):1755-1771. doi:10.1007/s00264-019-04334-w Hassan-Smith ZK, Jenkinson C, Smith DJ, et al. 25-hydroxyvitamin D3 and 1,25-dihydroxyvitamin D3 exert distinct effects on human skeletal muscle function and gene expression. PLoS ONE. 2017;12(2):e0170665. doi:10.1371/journal.pone.0170665 Martineau AR, Jolliffe DA, Hooper RL, et al. Vitamin D supplementation to prevent acute respiratory tract infections: systematic review and meta-analysis of individual participant data. BMJ. 2017;356:i6583. doi:10.1136/bmj.i6583 Ali N. Role of vitamin D in preventing of COVID-19 infection, progression and severity. 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Vitamin D myths 'd'-bunked. Nair R, Maseeh A. Vitamin D: The “sunshine” vitamin. J Pharmacol Pharmacother. 2012;3(2):118-126. doi:10.4103/0976-500X.95506 Centers for Disease Control and Prevention. Are there benefits to spending time outdoors? Sahota O. Understanding vitamin D deficiency. Age Ageing. 2014;43(5):589-591. doi:10.1093/ageing/afu104 US Preventive Services Task Force, et al. Screening for vitamin D deficiency in adults: US Preventive Services Task Force recommendation statement. JAMA. 2021;325(14):1436-1442. doi:10.1001/jama.2021.3069 National Institutes of Health Office of Dietary Supplements. Vitamin D: Fact sheet for health professionals. Nowak A, Boesch L, Andres E, et al. Effect of vitamin D3 on self-perceived fatigue: A double-blind randomized placebo-controlled trial [published correction appears in Medicine (Baltimore). 2017 Jan 20;96(3):e6038]. Medicine (Baltimore). 2016;95(52):e5353. doi:10.1097/MD.0000000000005353 Additional Reading National Institutes of Health, Office of Dietary Supplements. Vitamin D fact sheet for consumers. By clicking “Accept All Cookies”, you agree to the storing of cookies on your device to enhance site navigation, analyze site usage, and assist in our marketing efforts. Cookies Settings Accept All Cookies