![\"Estimated](\"https:\/\/www.prevention.com\/_assets\/design-tokens\/fre\/static\/icons\/clock-regular.4ddebeb.svg\")
5 min read<\/p>\n5 min read<\/p>\n
Some supplements and medications come with specific instructions on when and how to take them, while others you simply need to remember to take every day. But which category does vitamin D fall into? Turns out, determining the best time to take vitamin D isn\u2019t quite so simple.<\/p>\n
Vitamin D, a.k.a. calciferol, is a fat-soluble vitamin that plays many critical roles in the body. In addition to being found naturally in a few foods (and added to some others), it\u2019s also available as a dietary supplement and is produced by your body from exposure to UV rays, in a process known as vitamin D synthesis, per the National Institutes of Health<\/a> (NIH).<\/p>\n The benefits of getting enough vitamin D<\/a> include:<\/p>\n Meet the experts: Keri Gans, M.S., R.D.<\/a>, registered dietitian and author of The Small Change Diet; Jessica Cording, R.D.<\/a>, author of The Little Book of Game Changers<\/p>\n Here, dietitians share the most important factors to keep in mind if you\u2019re supplementing with vitamin D, including the best time to take it, whether to take it with food, and other considerations when choosing the best vitamin D supplement.<\/p>\n When is the best time to take vitamin D?<\/p>\n The short answer: It depends. Because vitamin D is fat-soluble, it\u2019s important to take it with food to enhance absorption, said Jessica Cording, R.D<\/a>., author of The Little Book of Game Changers. \u201cFor many people, that means taking it with a meal,\u201d she added. Beyond that, Cording suggested taking your vitamin D whenever you remember to take it.<\/p>\n If you prefer to take supplements in the evening, keep in mind that there is some mixed research around vitamin D\u2019s impact on sleep. Some older data<\/a> suggests that vitamin D may impact your body\u2019s production of melatonin<\/a>, which is a hormone that your brain produces in response to darkness and helps with the timing of your circadian rhythm. However, Cording pointed to newer studies<\/a> that suggest that maintaining adequate levels of vitamin D may actually help promote good sleep in people who are struggling. \u201cSometimes if I\u2019m working with somebody who is dealing with sleep disturbances, I\u2019ll have them shift to taking vitamin D at dinner,\u201d she said.<\/p>\n Basically, you can tinker with the timing and see how you feel\u2014increasing your serum concentration of vitamin D (or how much is available in your blood) is the most important thing.<\/p>\n Who should supplement with vitamin D?<\/p>\n If you think you might benefit from a vitamin D supplement, Cording said it\u2019s a good idea to talk to a healthcare provider before adding it to your routine. \u201cThe gold standard is really to get blood work done to see where you\u2019re at,\u201d she said. But Cording also pointed out that a large portion of the population doesn\u2019t get adequate amounts of this vitamin.<\/p>\n While it\u2019s still best to talk to a healthcare professional first, Cording said that the following groups are the most likely to benefit from a vitamin D supplement:<\/p>\n People who live in cold climates or are indoors a lot (they\u2019re not getting a lot of vitamin D from sunlight)People with darker skin tones (increased melanin levels in the skin reduce natural production of vitamin D3)Older adults (the skin\u2019s ability to naturally produce vitamin D3 decreases with age)People with medical conditions that impact fat absorption (since vitamin D is fat-soluble)People who eat a plant-based diet (since many vitamin D sources are from animal-based foods)How to choose a vitamin D supplement<\/p>\n When you\u2019re shopping for a supplement, you\u2019ll find two possible sources of vitamin D: Vitamin D2 and vitamin D3. Vitamin D2 comes from fortified foods and mushrooms, while vitamin D3<\/a> is produced in the skin when exposed to sunlight and is also found in animal-based foods, per the NIH<\/a>.<\/p>\n Between the two, Cording suggested choosing vitamin D3. \u201cIt\u2019s the most absorbable form,\u201d she said. Keri Gans, M.S., R.D.<\/a>, a registered dietitian and author of The Small Change Diet, agreed. \u201cI would opt for vitamin D in the form of D3 (cholecalciferol) which is more readily available to the body compared to D2 (ergocalciferol),\u201d she said.<\/p>\n Cording also suggested looking for vitamin D3 supplements that also contain vitamin K2. \u201cIt enhances the absorption even more,\u201d she explained.<\/p>\n How much should you take? The best way to get the right vitamin D dosage is to get a blood test to measure your serum vitamin D levels and to go from there, Cording said.<\/p>\n People who are on the lower end of normal or just below normal may benefit from taking 5,000 to 10,000 IU of vitamin D, according to Cording. Others may do well with 1,000 IU, while Cording said those who are truly deficient may need to take prescription-strength vitamin D. (But, again, that\u2019s something you should address with your doctor.)<\/p>\n If you are 70 years and older, your daily dose should be closer to 800 IU, noted Gans.<\/p>\n Can you take too much vitamin D?<\/p>\n Too much vitamin D can be toxic, making it important not to have too much. So, it\u2019s important to consult a physician before adding supplements to your diet. Vitamin D increases the absorption of calcium in your body, and having too much of it can cause high levels of calcium to circulate in your blood, per the NIH<\/a>.<\/p>\n That can lead to symptoms like nausea, vomiting, muscle weakness, mental health disturbances, pain, loss of appetite, dehydration, peeing a lot, feeling overly thirsty, and developing kidney stones, according to the NIH. In severe cases, having too much vitamin D may lead to kidney failure, heart issues, and even death. However, the NIH also notes that most adults can tolerate up to 4,000 IU of vitamin D per day without any risks.<\/p>\n Top foods rich in vitamin D<\/p>\n Vitamin D is more commonly found in animal products, like certain types of fish and fortified dairy products, per Cording.<\/p>\n