Vitamin D is an incredibly important vitamin, but it’s found in very few foods and is hard to obtain through diet alone.
As a large percentage of the world population is at risk of deficiency, vitamin D is one of the most common nutritional supplements.
However, many factors can influence its effectiveness, including when and how you take your daily dose.
This article explores the best time to take vitamin D to maximize its absorption and effectiveness.
Vitamin D stands out from other vitamins because it’s considered a hormone and is produced by your skin as a result of sunlight exposure (1).
However, vitamin D occurs in very few food sources — making it difficult to meet your needs if you’re not getting regular sun exposure.
Around 42% of adults in the US are deficient in this key vitamin (6).
Supplementing is an easy and effective way to meet your vitamin D needs, especially if you’re at risk of deficiency.
Summary Though vitamin D is produced by your skin in response to sunlight exposure, it’s found naturally in very few foods. Supplementing with vitamin D is an effective way to meet your needs and prevent deficiency.
Vitamin D is a fat-soluble vitamin, meaning that it does not dissolve in water and is absorbed best in your bloodstream when paired with high-fat foods.
For this reason, it’s recommended to take vitamin D supplements with a meal to enhance absorption.
According to one study in 17 people, taking vitamin D with the largest meal of the day increased vitamin D blood levels by about 50% after just 2–3 months (7).
In another study in 50 older adults, consuming vitamin D alongside a fat-heavy meal increased vitamin D blood levels by 32% after 12 hours compared to a fat-free meal (8).
Avocados, nuts, seeds, full-fat dairy products and eggs are nutritious sources of fat that help boost your vitamin D absorption.
Summary Studies indicate that having vitamin D with a large meal or source of fat can significantly increase absorption.
Many people prefer to take supplements such as vitamin D first thing in the morning.
Not only is it often more convenient, but it’s also easier to remember your vitamins in the morning than later in the day.
This is especially true if you’re taking multiple supplements, as it can be challenging to stagger supplements or medications throughout the day.
For this reason, it may be best to get in the habit of taking your vitamin D supplement with a healthy breakfast.
Using a pillbox, setting an alarm or storing your supplements near your dining table are a few simple strategies to remind you to take your vitamin D.
Summary Some people may find that taking vitamin D first thing in the morning is more convenient and easier to remember than taking it later on.
Research links vitamin D levels to sleep quality.
Conversely, one small study suggested that higher blood levels of vitamin D may be linked to lower levels of melatonin — the hormone responsible for regulating your sleep cycle — in people with multiple sclerosis (12).
Some anecdotal reports claim that taking vitamin D at night can negatively influence sleep quality by interfering with melatonin production.
However, scientific research to determine how supplementing with vitamin D at night may affect sleep is currently unavailable.
Until studies exist, it may be best to simply experiment and find what works best for you.
Summary Vitamin D deficiency may negatively impact sleep quality. Some anecdotal reports assert that supplementing with vitamin D at nighttime may interfere with sleep, but scientific data to that effect is unavailable.
Taking vitamin D with a meal can enhance its absorption and increase blood levels more efficiently.
However, there’s limited research on whether taking it at night or in the morning may be more effective.
The most important steps are to fit vitamin D into your routine and take it consistently to ensure maximum effectiveness.
Try taking it alongside breakfast or with a bedtime snack — as long as it doesn’t interfere with your sleep.
The key is to find what works for you and stick with it to ensure you’re meeting your vitamin D needs.
Summary Taking vitamin D with a meal can increase its absorption, but studies on specific timing are limited. For best results, experiment with different schedules to find what works for you.
Supplements can be an effective way to boost your blood levels of vitamin D, which is crucial to your health.
Taking vitamin D with food can enhance its effectiveness, as it's fat-soluble.
While the best timing has not been established, scientific data to confirm anecdotal reports that supplementing at night may interfere with sleep is unavailable.
Current research suggests you can fit vitamin D into your routine whenever you prefer.