October 31, 2023

What’s the Best Time to Take Vitamin D?

photo of Patrick Sullivan

Written By

Patrick Sullivan

photo of Shera Raisen, MD

Medically Reviewed By

Shera Raisen, MD

Lifeforce Physician

What’s the Best Time to Take Vitamin D?

Let’s shine a light on the sunshine vitamin. Vitamin D is one of the body’s best multitaskers — supporting strong bones, cardiovascular health, and immunity. In fact, Vitamin D controls the expression of 200+ genes, impacting nearly every cell in our bodies. (Read more about its many perks in this blog: What Your Doctor Wants You To Know About Vitamin D.) 

If you’re taking Lifeforce’s Vitamin D+K, you’re already reaping the benefits. But when is the best time to take vitamin D to maximize its advantages? We dig in and reveal the answers.  

The Best Time to Take Vitamin D

While there is no scientifically proven “best” time of day to take vitamin D, your body will absorb it more readily when taken with a meal. The time of day doesn’t affect how your body absorbs and uses vitamin D, so you should take it when it’s most convenient — and when you’re most likely to remember it. 

Should You Take Vitamin D in the Morning?

You can take vitamin D in the morning, and many people do. If you take other medications and supplements in the morning, adding vitamin D to your mix can help make it as easy as possible for you to remember to take it. 

Should You Take Vitamin D at Night?

There’s no evidence for or against any particular time to take vitamin D supplements. Many people choose to take vitamin D supplements in the morning to cut down on the chance that vitamin D disrupts their sleep, but any evidence for sleep disturbances with vitamin D is purely anecdotal.

In fact, there’s evidence that too little vitamin D can bring on sleep disorders, so it’s important to get as much as you need, be it morning or night.

Should You Take Vitamin D with Food?

Here’s one we can answer with an emphatic “Yes!” You should definitely take vitamin D with food, and more specifically, something with a little fat in it. That’s because vitamin D is fat-soluble, meaning it’s stored in fat tissue and — more importantly — your body has an easier time absorbing it when you take it with a little fat. 

Just a little food — such as yogurt, avocado, nuts, or something cooked in olive oil — will do the trick, according to Cleveland Clinic. However, one small study suggests that taking vitamin D with your largest meal of the day may increase absorption, so there’s no danger that you’ll eat too much food with your vitamin D supplement. 

Lifeforce Vitamin D+K

Vitamin D Timing Questions

You’ve probably heard vitamin D called the sunshine vitamin. That’s because your skin produces vitamin D when sunlight hits it. You may be concerned that vitamin D might interfere with your biological clock and keep you from sleeping, but here’s why you don’t have to worry.

Does Vitamin D Affect Sleep?

Vitamin D may affect sleep, but not negatively. Taking vitamin D at night won’t keep you up. Instead, producing melatonin — a hormone that helps regulate your sleep-wake cycle — when it’s time for bed depends on having a healthy level of vitamin D. It’s complicated, so here’s the short version:

Your skin produces vitamin D in response to sunlight. Your body takes that vitamin D and uses it to make serotonin. Your pineal gland then uses that serotonin to produce melatonin.

Pro Tip: Looking for a little more help catching your zzz’s? Go beyond melatonin and learn about 14 other supplements that can help you get more shuteye in our article, Sleep Vitamins: 15 Supplements to Take for Faster, Deeper Sleep.

Can Vitamin D Supplements Keep You Awake at Night?

There’s no convincing evidence that taking vitamin D supplements at night will “trick” your body into thinking it’s daytime. Some articles cite a small 2013 study that suggests vitamin D may suppress melatonin in people with multiple sclerosis (MS). 

However, because of the study’s small sample size and the MS involvement, it would be irresponsible to draw conclusions about non-MS sufferers. If you’re worried your vitamin D supplements will keep you up at night, or if you’re worried they have been, then by all means, take them earlier, or keep experimenting to find the best time for you.

Why Should You Take Vitamin D with Food?

There are two types of vitamins: water-soluble and fat-soluble. “Most vitamins are water soluble,” says Shera Raisen, MD, a Lifeforce Physician. Your body absorbs water-soluble vitamins easily, but doesn’t store them. Instead, it flushes out any excess with your urine.

Fat-soluble vitamins are vitamins D, K, E, and A, and they don’t absorb as easily,” says Dr. Raisen. Your body absorbs them in dietary fat, and stores the excess in fat cells. To help your gut absorb vitamin D supplements, it’s best to take them with food that contains some fat

Why Should You Take Vitamin D with Vitamin K?

Vitamin D and K work together to help support bone and vascular health, leading to lower risks for coronary heart disease and bone fractures. Taking these supplements together can also help you increase calcium absorption, which can help prevent osteoporosis.

Why Vitamin D + K

Vitamin D controls the expression of 200+ genes, touching nearly every cell in our bodies. Yet more than 40% of Americans are deficient in vitamin D. The Lifeforce D+K formula features a highly bioavailable form of vitamin D, CELLg8®, which has been shown to significantly raise vitamin D levels thanks to its liposomal delivery system that enhances absorption. The result: a supplement that supports bone health, immune health, and neurological function.

  • Features vitamin K2 to help ensure calcium is deposited safely into bones

  • Supports bone health, immune response, and cognitive function

  • Features vitamin K2 to help ensure calcium is deposited safely into bones

Pro Tip: Vitamin D absorption happens in the gut. To keep your digestive tract strong, try some of the methods from our article, The Gut-Immune Connection: 8 Ways to Strengthen Your Gut Microbiome.

How Long Does It Take for Vitamin D to Work?

About 800 to 1000 IU of vitamin D per day for a few weeks is usually enough to start to feel the short-term benefits. Those may include:

  • More energy

  • Less joint and muscle pain

  • Feeling stronger

However, most people with vitamin D deficiency have no symptoms, so it might be harder to notice it’s working.

Also, the length of time it takes for vitamin D to work depends on why you’re taking it in the first place. If you have a severe deficiency, you might be on a very high dose of vitamin D for six to eight weeks, and then a more modest maintenance dose thereafter.  

Whatever your reason for taking vitamin D, you should take it every day. A study of elderly people taking vitamin D supplements suggests that a daily dose is better than weekly or monthly, even if it works out to the same amount. 

Stick with your daily dose for a few weeks or months, and then get your levels checked with your doctor or the Lifeforce Diagnostic to be sure.

How to get more vitamin D

How to Get More Vitamin D

According to the National Institute of Health’s Office of Dietary Supplements (ODS), most adults should get about 600 IU of vitamin D per day

It can be tough to get that much vitamin D from food and sunlight, so a lot of people — about 18.5% of U.S. adults between 2017 and 2022, per a Centers for Disease Control and Prevention (CDC) report—take some form of vitamin D supplement.

Vitamin D from Food

You should look for fortified foods — milk is fortified with about 120 IU of vitamin D, according to the ODS — as well as: 

  • Cod liver oil

  • Trout

  • Salmon

  • Mushrooms

  • Sardines

  • Eggs

  • Beef liver

Of the foods on that list, only cod liver oil and trout will put you over the recommended 600 IU in one serving. On the other end of the spectrum, liver and eggs contain less than 50 IU. 

Vitamin D from Sunlight

It’s not a good idea to depend wholly or even mostly on sunlight to get your 600 IU of vitamin D per day. Vitamin D production in response to sunlight hinges on a large number of factors, most of which you can’t control, including: 

  • Season of the year

  • Location

  • Melanin content of your skin 

  • Age

  • Clouds and smog

  • Sunscreen 

“Sunscreen blocks the absorption and conversion into active vitamin D  that is supposed to happen in the skin,” says Dr. Raisen. “However, it's important to wear sunscreen to prevent sun damage and skin cancers,” she advises.  

When to Take Your Vitamin D Supplements

The best time to take vitamin D is a personal choice that comes best after experimentation. Take your vitamin D with food — preferably a little healthy fat — to make sure your body can get as much as it needs from your supplements. 

“It probably is best to take it with some type of fatty snack or meal. But I personally take mine on an empty stomach at bedtime, and my levels have gone up just fine,” says Dr. Raisen. 

Remember, getting your daily dose of vitamin D is more important than the time when you take it. Just be consistent, and you’ll reap the many benefits of this essential nutrient. 

This article was medically reviewed by Shera Raisen, MD, ABFM Board Certified in Family Medicine. 

Disclaimer: These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease. 

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Vitamin D controls the expression of 200+ genes, touching nearly every cell in our bodies. Yet more than 40% of Americans are deficient in this essential vitamin. The Lifeforce D+K formula, the only one of its kind to feature ampli-D®, is clinically proven to raise vitamin D levels three times faster than regular Vitamin D supplements. Lifeforce D+K delivers the most bioavailable and bioactive form of supplemental vitamin D (calcifediol as ampli-D®) to bolster bone health, immune, and neurological function. The addition of a vitamin K1 + K2 blend ensures that calcium is deposited in the bone, versus the soft tissue, for maximum results.