When you’ve just been pregnant, you get countless tips, some helpful, some not (telling yourself to “make sure you get plenty of sleep” when you’re suffering from pregnancy-induced insomnia isn’t exactly what you want to listen). One thing you probably know from your doctor or friends is that you are supposed to take a prenatal vitamin, but some might also recommend vitamin B12 during pregnancy. Sounds healthy enough, but do you need the extra B12 supplement during pregnancy?
If you’ve heard of B12, it may be because for a brief period in the early 10’s various celebrities including Madonna, Justin Timberlake and Charlize Theron injected themselves with this vitamin and touted it as a cure for everything. from depression to exhaustion. (You won’t be surprised to learn that this isn’t something most people need to do – there’s little evidence to back up claims that injecting B12 gives you more energy). But B12 is an important vitamin for everyone, and is especially important if you are pregnant or breastfeeding. So what is B12, why do you need it, and how can you make sure you’re getting enough?
What is Vitamin B12?
Vitamin B12 is one of eight B vitamins (not twelve, just to confuse things – the substances known as B4, B10 and B11 are not officially considered vitamins). The Mt. Sinai Hospital website notes that all eight “B” vitamins are needed for many different bodily functions, including maintaining the health of your teeth, eyes, skin, and liver.
Specifically, vitamin B12 “is important in the development of red blood cells, and vitamin B12 deficiency can lead to macrocytic anemia,” Atlanta-based obstetrician-gynecologist Dr. Zuri Hemphill-Bryant tells Romper via email. . Macrocytic anemia occurs when your body doesn’t have enough normal red blood cells and can cause symptoms such as “muscle weakness and paresthesia” (paresthesia is the technical term for the “pins and needles” sensation on your skin).
Why is vitamin B12 important for pregnancy and postpartum?
Everyone needs this vitamin, but it’s especially crucial if you’re pregnant or nursing a new baby. In an article published in the medical journal Nutrition reviewresearchers at UC-Davis noted that “most adults can tolerate a diet deficient in vitamin B12 . . . for years without developing clinical symptoms of deficiency”, but that “newborns have ” “limited” liver stores (this is the term for liver cells needed for liver function). Dr. Hempill-Bryant explains that babies born to mothers who are vitamin B12 deficient “will also be vitamin B12 deficient, especially if they are are then exclusively breastfed”. A study in the Journal of Childhood Neurology found that the most severe cases of vitamin B12 deficiency can lead to “weakness, growth retardation, afebrile seizures, developmental delay, nystagmus, tremors and involuntary movements” in young babies.
How can you make sure you’re getting enough B12?
Despite these frightening possibilities, Hemphill-Bryant has reassuring information: “Most people get all the vitamin B12 they need from their diet. Vitamin B12 is mainly found in animal-based diets. So if you eat a varied diet and don’t have a lab-documented vitamin B12 deficiency, you don’t need additional supplementation. However, she explains, “people who follow a strict vegan or vegetarian diet are much more likely to be at risk of vitamin B12 deficiency, and they should take a vitamin B12 supplement, especially when they are pregnant or trying to become pregnant.
Another group at risk for low vitamin B12 levels are those who have had gastric bypass surgery or have other stomach problems, such as ulcers. Finally, the greatest risk is for people with ‘pernicious anemia’, a rare condition in which a person is unable to absorb vitamin B12 through the stomach or intestines – people with this condition are those who Actually need B12 injections.
Basically, if you eat a diet that includes shellfish, salmon, liver, and eggs, among other foods, you probably don’t need to worry too much about whether you or your baby has this deficiency. Your doctor can do a blood test if you are worried. And Hempill-Bryant reminds his patients that regardless of your diet, you need a prenatal vitamin that includes folic acid, otherwise known as vitamin B9. B9 and B12 are two of the “Bs” you shouldn’t miss if you’re planning to welcome a new B (baby!) into your family.
Zuri Hempill-Bryant, MD, https://doctors.piedmont.org/provider/Zuri+Dana+Hemphill-Bryant/2014117
Goraya JS, Kaur S, Mehra B. “Neurology of vitamin B12 nutritional deficiency in infants: case series from India and literature review.” J Child Neurol. 2015 Nov;30(13):1831-7. doi: 10.1177/0883073815583688. Published online May 7, 2015. PMID: 25953825.
Dror DK, Allen LH. “Effect of vitamin B12 deficiency on neurodevelopment in infants: current knowledge and possible mechanisms.” Nutr Rev. 2008 May;66(5):250-5. doi:10.1111/j.1753-4887.2008.00031.x. PMID: 18454811.