Ultimately both vitamin D2 and D3 get converted through enzymatic reactions in the liver and kidneys to the active form of vitamin D and can be taken together [1]. So, in simple terms, the answer is YES! You can take vitamin D and D3 together.
What's the difference between vitamin D and vitamin D3? There are two possible forms of vitamin D in the human body: vitamin D2 and vitamin D3. Both D2 and D3 are simply called “vitamin D,” so there's no meaningful difference between vitamin D3 and just vitamin D.
Taking a multivitamin with vitamin D may help improve bone health. The recommended daily amount of vitamin D is 400 international units (IU) for children up to age 12 months, 600 IU for people ages 1 to 70 years, and 800 IU for people over 70 years.
Certain medications (bile acid sequestrants such as cholestyramine/colestipol, mineral oil, orlistat) can decrease the absorption of vitamin D. Take your doses of these medications as far as possible from your doses of vitamin D (at least 2 hours apart, longer if possible).
Magnesium and vitamin D3
Magnesium and vitamin D3 supplements can be taken together to ensure that the body functions adequately. Magnesium is important for the body to make vitamin D3 absorbable, and enzymes in the liver and kidneys require magnesium to break down vitamin D3.
Large doses of minerals can compete with each other to be absorbed. Don't use calcium, zinc, or magnesium supplements at the same time. Also, these three minerals are easier on your tummy when you take them with food, so if your doctor recommends them, have them at different meals or snacks.
Some studies suggest that the body may not be able to absorb vitamin K as efficiently when taken with vitamins D and E. As a result, taking a large dose of these three vitamins together may prevent vitamin K from clotting the blood effectively [7].
There's no set time of day that's best to take vitamin D supplements. Some people say taking vitamin D supplements at night is an insomnia risk. There's no research to confirm this, but you might want to take your supplement earlier in the day if you think it's screwing with your sleep.
Vitamins D, E and K
Airey says it's “simply not efficient” to take them together as your body's ability to absorb the vitamins will be reduced if you take them together.
The main consequence of vitamin D toxicity is a buildup of calcium in your blood (hypercalcemia), which can cause nausea and vomiting, weakness, and frequent urination. Vitamin D toxicity might progress to bone pain and kidney problems, such as the formation of calcium stones.
In conclusion, vitamin D3 can be taken as a prophylactic drug for hypertension by the elderly and obese folks with vitamin D deficiency who are at high risk of hypertension. Vitamin D3 can be used as an adjuvant drug to control the blood pressure on hypertension patients with vitamin D deficiency.
“Adding an over-the-counter vitamin D supplement can make improvements in just three to four months time.
The two top times to supplement with Vitamin D are in the morning and with a meal, preferably breakfast or lunch. First thing in the morning: There are many benefits to taking Vitamin D in the morning. The biggest benefit is that if you do it first thing, you won't forget about it later.
A study found that 32% more Vitamin D3 is absorbed by the body when it is taken with a meal. It is also important to note that taking any kind of supplement (not just fat-soluble ones) on an empty stomach causes some people gastrointestinal distress, including nausea or vomiting.
"Adequate levels of magnesium in the body are essential for the absorption and metabolism not only of vitamin D but of calcium as well," Dean states. "Magnesium converts vitamin D into its active form so that it can help calcium absorption.
Since vitamin D is fat soluble, it's best not to take it on an empty stomach. For maximum absorption, take it with a substantial meal, and preferably one that includes fat-containing foods like nuts, seeds, and eggs.
If you are supplementing with vitamin D3, it's imperative you have enough magnesium to activate it. Why is this so important? Vitamin D3 cannot be utilized without sufficient magnesium; it simply remains stored in the body until it has enough magnesium to be activated.
Taking D2 and D3
The two types of vitamin D have no negative interactions with each other, so you can safely take them together. However, the body converts both forms of vitamin D to the same active form, called calcitriol.
Magnesium assists in the activation of vitamin D, which helps regulate calcium and phosphate homeostasis to influence the growth and maintenance of bones. All of the enzymes that metabolize vitamin D seem to require magnesium, which acts as a cofactor in the enzymatic reactions in the liver and kidneys.
Yes! You can and should take magnesium and vitamin D together. In fact, the bioavailability of vitamin D largely relies on magnesium. Also, many nutrients wouldn't work efficiently without magnesium, further highlighting the importance of this mineral!
Supplementing vitamin B6 may improve sleep quality and duration. A 2019 study also found that taking a supplement of magnesium, melatonin, and vitamin B complex for 3 months improved sleep and helped treat insomnia.
You can—but it's probably not a good idea. For some supplements, optimal absorption can depend on the time of day taken. Not only that—taking certain vitamins, minerals, or other supplements together can also reduce absorption and may result in adverse interactions, which can be harmful to your health.