Research is mixed on whether the average woman with ample access to nutritious foods actually benefits from taking supplements – particularly since the U.S. Food and Drug Administration (FDA) doesn’t monitor them for safety or effectiveness, and some alleged health elixirs can cause more harm than good.
“There’s not a lot of evidence that taking any vitamin when you don’t have a deficiency does anything particularly helpful,” says registered dietitian Alissa Rumsey, founder of Alissa Rumsey Nutrition and Wellness.
And yet? It’s tempting to pop pills to address specific health concerns or as a backup in case your diet falls short. Although you should always talk to your doctor before taking new vitamins, since some can cause adverse reactions, interact with other medications, or interfere with existing health conditions, this guide will help you suss out the best supplement for you based on your needs:
Growing a healthy human requires some special sauce that an ordinary diet might not deliver daily: You need at least 600 micrograms (mcg) of folic acid (aka folate) to help prevent fetal defects in the brain and spine; 27 mg of iron to help the body create blood that supplies oxygen to the fetus, plus 85 milligrams (mg) of vitamin C to promote iron absorption; and nutrients like calcium (1,000 mg per day) and vitamin D (15 mcg or 600 international units) to build the fetus’s bones and teeth, according to The American College of Obstetricians and Gynecologists and the National Institutes of Health Office of Dietary Supplements.
Although the nutrients above occur naturally in various foods, taking a prenatal multivitamin that contains ample amounts of each will ensure your precise needs are fulfilled, according to the ACOG. And if you breastfeed after giving birth, which can deplete your nutrient stores, your doctor might tell you to continue taking prenatal vitamins to help avoid deficiencies.
Research suggests vitamin C, an antioxidant that’s also found in citrus fruits, peppers, strawberries, leafy veggies, and more, can help prevent and shorten illness in part thanks to its antimicrobial properties and the way it supports immune cells — it’s why Rumsey has been taking 1,000 mg a day for three years. “I find that when I do get a cold, the duration is much shorter,” she says, estimating her symptoms now last for just a day or two, rather than for up to a week.
When Rumsey deviates from her typical routine, she keeps her digestive system on track with probiotics, which she takes in capsule form daily. “I am much more regular, especially when I travel,” says the dietitian of how she benefits from the supplement. She now partners with the brand she takes.
Rumsey also recommends taking probiotics to restore healthy gut bacteria whenever you take antibiotics, which can kill good gut bacteria along with the bad and lead to diarrhea. Although more research is needed to suss out proper dosage and probiotic makeup, a 2012 meta-analysis of 82 studies suggests the supplements can reduce adverse effects.
Calcium is an essential nutrient for bone health. If you’re lactose intolerant or prefer to avoid dairy, which is one of the best calcium sources, you can still get your daily dose of about 1,000 mg per day through non-dairy-fortified dairy substitutes like soy milk, and foods like salmon and sardines, says Jennifer Haythe, MD, an internist and cardiologist at New York-Presbyterian Hospital.
Because superfluous calcium supplementation can lead to kidney stones and constipation and interfere with the absorption of iron and zinc, it’s best not to load up on calcium supplements unless there are gaps in your diet or symptoms of deficiency, like bone loss. However, if your doctor does steer you toward calcium supplements, take it with vitamin D to promote proper absorption, and in two 500-mg increments, since it’s best absorbed that way, Dr. Haythe says.
“A deficiency of B vitamins like biotin can cause patients to develop brittle nails and thinning hair,” Dr. Zeichner says. Although there’s no statistically significant data that shows biotin supplements improve the strength or appearance of hair or nails, “there’s no harm in taking it as long as you have no medical issues,” he says, noting that anecdotally, many of his patients who supplement with biotin are pleased with the results.
“Rather than trying to reinvigorate damaged skin cells down the road, you can support the healthy functioning of skin cells to promote a strong foundation before cell health declines,” Dr. Zeichner says. Enter collagen, the mortar that holds together skin cells. When taken orally, your body breaks down collagen into its fundamental parts — amino acids — and circulates them in the blood stream. Research suggests this may help provoke new collagen production in the skin, effectively improving signs of aging.
Research suggests that zinc, found in red meat, seafood, fortified cereals, meats, nuts, and dairy, has anti-inflammatory properties that may alleviate acne, Dr. Zeichner says. The typical dose is 8 mg per day or up to 12 mg per day if you’re pregnant or breastfeeding, although it’s safe for all adults to take up 40 mg per day.
Vitamin B12 only occurs naturally in animal products. Although it’s added to fortified breakfast cereals, only a small amount of the vitamin B12 you ingest is actually absorbed — one reason why it’s smart to supplement if you follow a plant-based diet.
Research suggests its best to take 1,000 mcg of B12 two to three times per week for optimal absorption if you forgo animal products.
Found in fortified cereals, lean meats, seafood, and spinach, the mineral is needed to produce red blood cells and fend off symptoms of anemia like fatigue, weakness, cold hands and feet, and headaches. But women lose iron, which is found in period blood, during every cycle.
Your doctor can do a routine blood test to check if your levels are low. Most women need about 18 mg of iron a day, but you don’t want to overdo it, since taking more than 20 mg worth of iron supplements can mess with your stomach and absorption of other vitamins, according to The National Institutes of Health Office of Dietary Supplements.
Vitamin D is found in fortified cereals and fish, but your skin can create ample amounts of it in response to sunlight exposure. If your diet falls short, and you get less than five minutes of sun exposure on sunscreen-free skin between 10 a.m. and 3 p.m. at least twice a week, you might need a little help from supplements to fend off symptoms of deficiency, which can include bone weakness and muscle weakness, and seasonal affective disorder marked by depression. Most women need about 20 mcg (or 800 international units) per day, according to the National Institutes of Health Office of Dietary Supplements, but because only small amounts of the supplements you take will actually be absorbed, shoot for about 2000 IU (25 mcg) of vitamin D per day.
While there’s no pill that will shield you from unprotected sun exposure, this Heliocare contains polypodium leucotomos, an antioxidant proven to reduce the skin’s inflammatory response to UV light. “It does not take the place of sunscreen,” Dr. Zeichner warns, adding that supplement’s brand name matters in this case since its exact formula has been tested — and there’s no saying, without clinical trials, whether alternatives deliver results. “It’s recommended alongside traditional sunscreen and protective behaviors.”
Trouble sleeping could be caused by bad bedtime habits like drinking caffeine, which can perk you up, or using your phone or TV too late at night, which can mess with your circadian rhythm. Enter melatonin, the hormone your brain releases in the evening to lull you to sleep. Research suggests taking 2 or 3 mg at your ideal bedtime may help you nod off faster and reduce difficulty sleeping due to jet lag, although more research is needed on timing.
Although the science is still evolving, and it’s unclear whether supplements work as well as a diet that’s rich in seafood, nuts and seeds, and plant oils, researchers have uncovered some promising benefits linked to the omega-3 fatty acids found in fish oil supplements, which may help protect you from chronic diseases including breast and colorectal cancer, Alzheimer’s, dementia, rheumatoid arthritis, and heart disease, according to the National Institutes of Health Office of Dietary Supplements. There are no guidelines regarding dosage for omega-3, but you don’t want to top 2 grams a day, which can amp up the risk of unpleasant side effects like stomach issues and foul-smelling breath and sweat. These squeeze shots, which contain just 2000 mg of fish oil, will keep you in the clear.