Due to its special role, vitamin B12 aids in the prevention of anemia, which mostly leads to fatigue. Even though the research available about the relationship between vitamin B12 and insomnia remains unclear, some studies² show that elevated levels of vitamin B12 do cause sleeplessness.
Vitamin B12, for example, should definitely be taken in the morning. This is because it is important for energy metabolism, which may interrupt your sleep if taken at night.
Growing evidence has demonstrated that vitamin D has a role in sleep regulation [12]. Specifically, vitamin D deficiency (VDD) can increase risk of sleep disorders and is associated with sleep difficulties, shorter sleep duration, and nocturnal awakenings in children and adults [13,14,15].
People who are concerned about their low level of energy should be advised that unless they already suffer from a vitamin B12 deficiency, there is no strong evidence to support the notion that taking large doses of vitamin B12 will increase their energy levels.
There is no specific time of day recommended when you should take vitamin B-12 supplements, as there is no clinical evidence demonstrating a significant difference between taking vitamin B-12 in the morning or at night.
Vitamin B12 helps increase the body's production of melatonin, making it important for regulating sleep-wake cycles. Higher B12 levels have been associated with a lower risk of depression.
B12 injections may contribute to low potassium levels in your body. Though rare, this reaction can cause muscle cramping, extreme fatigue, and an irregular heartbeat.
B Complex Vitamins
I would discourage people from taking a B complex and instead get it from food sources. Especially since taking one before bed can keep you awake.
On the other hand, some supplements, especially energy drinks, weight loss supplements, and cocoa products, as well as red yeast rice, garlic, policosanol, DHEA, chromium and high doses of vitamin D, vitamin b-12, potassium and coenzyme Q10 might interfere with sleep.
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.
Many factors can cause a person to wake up often at night. Needing to urinate is a common reason, but sleep apnea, overheating, and dietary habits are just a few of the others. However, regularly waking up in the middle of the night can become problematic, as it interrupts sleep.
Safety and side effects
High doses of vitamin B-12, such as those used to treat a deficiency, might cause: Headache. Nausea and vomiting. Diarrhea.
Vitamin B12 is considered an important brain and nervous system micronutrient and is often used for anxiety. It helps to ensure normal function for your nerves, which can help combat physical symptoms of anxiety.
Interactions between your drugs. No interactions were found between Vitamin B12 and Vitamin D3. However, this does not necessarily mean no interactions exist. Always consult your healthcare provider.
One Possibility: Supplement Allergies
Thus if you're otherwise healthy but still continue to feel tired after taking a B-12 supplement, it could be a sign of a mild allergic reaction. If a rash, difficulty breathing or swelling coincides with taking your dose of B-12, get to the doctor right away.
Vitamin B12 deficiency can have distressing neuropsychiatric symptoms. It can have an etiological role in clinical presentations like depression, anxiety, psychosis, dementia, and delirium, requiring screening of at-risk populations.
Can magnesium cause insomnia? Magnesium does not cause insomnia. A magnesium deficiency, however, can. As discussed above in this article, we recommend healthy doses of magnesium through diet or supplements to help combat insomnia.
One study of older adults with insomnia found that magnesium supplementation at a dose of 500 milligrams daily for eight weeks helped them fall asleep faster, stay asleep longer, reduced nighttime awakenings, and increased their levels of naturally circulating melatonin.
Fatigue. Megaloblastic anemia due to vitamin B-12 deficiency may lead to a person feeling fatigued. Without enough red blood cells to carry oxygen around their body, a person can feel extremely tired.
Vitamin B12 deficiency can indeed lead to weight gain. But the weight gain is not a direct result of the deficiency. Instead, vitamin B12 deficiency causes lethargy or lack of energy, and in turn, inactivity causes weight gain.
“Some foods and drinks can interfere with vitamin B complex intake like alcohol, caffeine and processed foods, etc should be avoided completely,” Shah added.
You can definitely opt for taking vitamin B12 supplements at night if that's what works best for you, although the natural energy-boosting abilities of vitamin B12 might be put to better use as you're starting the day.
You may be able to stop taking cyanocobalamin when your vitamin B12 blood levels are back to normal. However, you may need to take it for the rest of your life if your diet does not have enough vitamin B12 or you cannot absorb enough vitamin B12 from your food.