If you toss, turn and count sheep all night to no avail, you know the struggle to get the sleep you need is real. It would be nice to be able to take one magic vitamin, call it a day and hit the hay for sweet slumber. Unfortunately? Sleep experts say that Rx doesn’t exist. In fact, some vitamins can interfere with sleep.
“Vitamins might not seem like they’d impact your sleep much, but some of them play key roles in regulating things like melatonin, brain chemistry and your circadian rhythm,” explains Dr. Raj Dasgupta, MD, the chief medical Advisor for Sleepopolis. “So, if you’re taking a supplement, especially without knowing whether you need it, it could throw off your sleep in subtle ways.”
He has worked with patients who were taking vitamins to “feel healthier” only to develop nightmare sleep habits. “It’s important to understand what you’re putting into your body and how it might interact with your sleep-wake cycle,” he says.
Dr. Dasgupta and other experts caution that taking this specific vitamin can be particularly risky for sleep.
The Surprising Vitamin That Can Ruin Your Sleep
Taking vitamin B12 supplements may cause you to burn the midnight oil, experts warn.
“Overly high levels of B12 can lead to sleep fragmentation and earlier waking,” explains Dr. Alex Dimitriu, MD, who is double board-certified in psychiatry and sleep medicine specialist and the founder of Menlo Park Psychiatry & Sleep Medicine.
It may surprise you, given that Vitamin B12 is essential for sleep regulation. “Vitamin B12 is involved in energy production and nervous system function, which sounds like a good thing, but it can be too stimulating for some people,” Dr. Dasgupta reports. “It’s not a sedative vitamin. It’s actually the opposite in many ways. Taking it too late in the day, or in higher doses, might interfere with your ability to wind down or stay asleep, especially if your system is already sensitive to changes in rhythm.”
Research on vitamin B12 and sleep is mixed and inconclusive, adding to the confusion for people trying to make the best health choices. For instance, one study found that high vitamin B12 levels in the blood could put people with Type 2 diabetes at a higher risk for developing insomnia. Additionally, an older 2009 research review cited studies that found vitamin B12 could alter sleep-wake rhythms.
Yet, other research finds that low levels of B12 might increase a person’s odds of insomnia (it is involved in sleep regulation, after all). A 2024 study of 238 individuals with low vitamin B12 levels found that participants experienced improvements in sleep after receiving B12 injections for two months.
What gives? The simple answer: two things can be true.
“B12 is one of the micronutrients that is part of melatonin production,” explains Dr. Stephen Carstensen, DDS, a dentist and sleep expert. “Melatonin is a key to brain systems that manage our sleep-wake cycles. Taking more B12 won’t help sleep, but not having enough may affect the sleep drive we depend on.”
That said, it’s really unlikely you’re vitamin B12 deficient. “B12 is stored in our liver, in about a five to six year supply, so unless someone is malnourished for a long time—years—it is likely that their B12 levels are normal,” Dr. Dimitriu says. “Given the body’s extensive ability to manage B12 levels in normal, healthy, non-malnourished adults, supplementing B12 is not recommended.”
Related: Here’s Exactly What Happens to Your Body When You Don’t Get Enough Sleep
Signs Vitamin B12 Is Wrecking Your Sleep
If you’re racking your brain trying to determine why you suddenly stopped sleeping, you may need to backtrack a bit. Dr. Dasgupta suggests that people taking vitamin B12 reflect on when the interrupted sleep began. Was it around the time you started using vitamin B12?
“If you started taking B12 recently and now you’re having trouble falling asleep, waking up during the night, or feeling wired at bedtime, that’s a possible red flag,” he says.
Of course, Dr. Dimitriu says many factors can affect sleep on their own or in combination with vitamin and supplement use, including:
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Stress
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Anxiety
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Substance use (like drinking too much alcohol)
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Inconsistent sleep-wake times
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Screen time too close to bed
Related: Cardiologists Say This Bedtime Habit Is Linked to Lower Heart Attack Risk
How Much Vitamin B12 Do You Need Per Day?
The Office of Dietary Supplements states that adult men and women who aren’t pregnant or breastfeeding should aim to consume 2.4 mcg of vitamin B12 per day. The recommended intake is 2.6 mcg per day for pregnant people and 2.8 mcg for breastfeeding parents.
“B12 is one of the key vitamins that our bodies cannot make for ourselves, yet it’s critical for some key body functions, such as sleep regulation,” Dr. Carstensen stresses.
However, he advises people to adopt a food-first approach to nutrition. You can find vitamin B12 in:
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Fortified cereals
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Oysters
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Salmon
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Milk
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Yogurt
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Eggs
Related: The 5-Step Bedtime Routine of People Who Never Gain Weight
Other Ways To Get More Sleep
Sleep experts don’t recommend supplementing with vitamin B12 because high levels of it can interfere with sleep. They shared more natural ways to catch some Zzz’s.
1. Give your devices a curfew
Dr. Dimitriu regularly tells patients to give their devices an earlier bedtime than they give themselves.
“‘Tech off at 10,'” he recommends. “Allow your body time to wind down before sleep—so nothing interactive, and certainly no screens or ‘search and find’ behavior, like shopping, scrolling and news feeds.”
2. Go dark
Artificial light didn’t always exist—people used to go to sleep and wake up with the sun. You can recreate that vibe in your home. “Have dim lights on at home after 9,” Dr. Dimitriu says. “Blue lights limit melatonin production, while dim, sunset-color lighting is what the body needs before bedtime.”
3. Focus on wake times
Dr. Dimitriu notes that it’s easier to control when you wake up than when you say, “Good night, moon.”
“If you have trouble sleeping at night, try waking earlier in the morning, and get bright light within 30 minutes of waking,” he says.
As important as sleep is, there’s such a thing as too much of it, though.
“Do not oversleep, as this can result in next-day insomnia—I call this ‘flip-flop insomnia,’ which I often see in people who sleep too little, then too much on alternating nights,” he explains.
4. Control what you can
If you’re experiencing significant and consistent sleep trouble, consult a specialist for an evaluation. “Snoring and sleep apnea are breathing disorders that cause inflammation and brain disruptions that prevent healthy sleep,” Dr. Carstensen says. “Breathe better, sleep better—ask your dentist or primary care doctor.”
5. Find support
Sometimes, lifestyle tweaks and even CPAP machines only take you so far. Especially if stress and anxiety have you tossing, turning and waking up at 3 a.m.
“It is essential to mention that cognitive behavioral therapy for insomnia (CBT-I) is widely considered the primary and most effective treatment for insomnia,” Dr. Dasgupta shares.
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Related: 107 Insomnia Quotes for When Those Long, Restless Nights Feel Like They’ll Never End
Sources:
This story was originally reported by Parade on Oct 28, 2025, where it first appeared in the Health & Wellness section. Add Parade as a Preferred Source by clicking here.