Some say to take it in the morning. Others say never to take it at night. But what does the actual science say?
Smart supplement consumers do their research and choose the best version of the ingredient they're interested in. They might look at the dosage, the number of bioactive components, and the supplement's delivery system. Then, they ask the most common question: "When's the best time to take it?"
Sometimes timing matters; sometimes not. But there's always been some confusion about certain supplements, like vitamin D. Is there a best time to pop that pill? Based on the evidence, the definitive answer is... maybe? Here's what we know.
The basics
First, taking vitamin D consistently is the most important factor. The time of day you take it isn't as important as, well, remembering to take it.
Second, several nutrients enhance vitamin D absorption, activation, and utilization in the body. Vitamin D is fat-soluble, so consuming it with dietary fat improves its absorption in the gut. But that may be less important if you're using the microencapsulated form of vitamin D.
Adequate K2 plays a role, as do magnesium and zinc. Magnesium, for example, is essential for converting vitamin D into its active form (calcitriol), so be sure you're topped off by taking a chelated mineral supplement like ElitePro Minerals (Buy at Amazon). Fish oil also enhances the transport and activation of vitamin D. You don't have to take those supplements at the same time you take vitamin D; you just don't want to be deficient in those nutrients.
Does time of day matter?
There are a couple of theories on this:
1. Some say to avoid taking vitamin D at night.
Anecdotally, people claim it "gives them energy" and affects sleep. The evidence, however, is mixed. While vitamin D is critical for cellular energy production, it's not a stimulant. Feeling immediate energy from taking vitamin D is considered "psychological" in the research, meaning if you think it'll give you energy it probably will, but it's mostly in your head.
Now, if a person is very deficient in vitamin D, they may indeed feel more energetic when they pump their blood levels up, but this is more of a correction of fatigue symptoms. Two different meta-analyses concluded that adequate levels of vitamin D actually improve sleep quality.
Short answer: You can take vitamin D at night.
2. Some say to take vitamin D in the morning.
Their thinking? Vitamin D mimics circadian rhythms related to morning sunlight exposure. Your circadian rhythm regulates melatonin and cortisol, so taking vitamin D in the morning aligns with this natural rhythm, supporting the body's internal clock. It makes sense, but again, the actual evidence is limited.
So, what's the answer?
Research hasn't definitively proven the optimal time for taking vitamin D, so do whatever you think works best, just be consistent.
Ideally, use microencapsulated D3. This form uses something called caprylocaproyl polyoxyl-8 glyceride. Pharmaceutical companies use it to enhance the absorption and bioavailability of drugs, and it's also used in vitamin D supplements like D Fix High Absorption Vitamin D (Buy at Amazon).
