Should Women Take Supplements? Sources and Dietary Needs
Women have specific nutrient needs that change throughout their lifespan. For example, teens have different nutrient needs than postmenopausal women, and pregnant and breastfeeding women require greater amounts of specific nutrients than non-pregnant women.
What’s more, nutrient needs may differ depending on your overall health and lifestyle. Although vitamin supplementation isn’t necessary for all women, some may need to supplement to reach their recommended intake levels.
This article reviews vitamins for women, including vitamin sources, dietary needs, and why some women may benefit from supplementation.
Vitamins are divided into 2 categories: water-soluble and fat-soluble.
The water-soluble vitamins consist of eight B vitamins: B1 (thiamine), B2 (riboflavin), B3 (niacin), B5 (pantothenic acid), B6 (pyridoxine), B7 (biotin), B9 (folate), and B12 (cobalamin), as well as vitamin C (
Vitamins A, D, E, and K are considered fat-soluble vitamins.
Water-soluble vitamins are not readily stored in your body and need to be supplied continuously through your diet. On the other hand, fat-soluble vitamins are stored in your body’s tissues and retained for longer periods (
Depending on their age and health status, women and teens have differing daily vitamin needs.
Note that women who smoke need an extra 35 mg of vitamin C per day. Also, pregnant and breastfeeding women under the age of 19 need 5 mg less vitamin C per day than pregnant and breastfeeding women 19 years or older (
Notably, some argue that the daily vitamin D needs of pregnant and breastfeeding women are much higher than the current recommendations. This will be discussed later in this article (
Both water- and fat-soluble vitamins are needed for critical bodily processes, which is why a vitamin deficiency can lead to adverse health outcomes.
Water-soluble vitamin functions
Water-soluble vitamins play many important roles in your body. The B vitamins are perhaps best known for their roles in energy production, while vitamin C is best known for its role in immune function.
However, these nutrients are involved in many other critical processes as well.
B1 - Thiamine helps convert nutrients into energy and is required for proper cellular function. Pregnant women, women on long-term diuretic medication, and women who have undergone bariatric surgery are at a greater risk of thiamine deficiency (
B2 - Riboflavin is needed for energy production and growth and development. It also functions as an antioxidant. Pregnant and breastfeeding women, women with eating disorders, and older women are at a greater risk of developing a B2 deficiency (
B3 - Niacin is essential to nervous system function, energy production, and enzymatic reactions. Niacin deficiency is rare in the United States, but women with a deficient intake of niacin-rich foods may be at risk (
B5 - Pantothenic acid is a precursor to coenzyme A, which is needed for various essential processes, such as the production of hormones and neurotransmitters. A deficiency in B5 is extremely rare (
B6 - Pyridoxine is important for macronutrient metabolism, immune function, and neurotransmitter production. Certain populations, such as women with obesity and autoimmune diseases, are more likely to have low B6 levels (
B7 - Biotin plays a key role in energy production and the regulation of oxidative stress. Women who are pregnant, those who excessively use alcohol, and women on certain medications are more likely to have low biotin levels (
B9 - Folate is needed to produce DNA, RNA, red blood cells, proteins, and neurotransmitters. A deficiency can result from inadequate dietary intake, malabsorption conditions, medication interactions, pregnancy, alcohol dependence, and more (
B12 - B12 is essential for neurological functioning and red blood cell and DNA production. A deficiency can result from inadequate dietary intake or medical conditions, including autoimmune diseases and malabsorption (
Vitamin C - Vitamin C acts as a powerful antioxidant and plays a role in immune function and collagen and neurotransmitter production. Smoking and excessive drinking increase the risk of vitamin C deficiency (
Note that choline is a water-soluble nutrient often grouped with B vitamins due to its similar functions in the body. However, choline is not a vitamin and found in both fat- and water-soluble forms in the diet.
This nutrient plays an important role in brain development, metabolism, neurotransmitter synthesis, and more. Choline needs increase during pregnancy and breastfeeding (
Fat-soluble vitamin functions
Vitamin A - Vitamin A is essential for healthy vision, immune function, cellular growth, and fetal development. Women with cystic fibrosis and women in developing countries are at a greater risk of vitamin A deficiency (
Vitamin D - Vitamin D deficiency is common. This vitamin plays an important role in maintaining calcium levels, insulin production, and immune function. Women with obesity, older women, African-American women, and hospitalized women are most at risk of deficiency (
Vitamin E - Vitamin E acts as an antioxidant and is needed for cellular communication and blood vessel and immune health. Vitamin E deficiency is rare but can occur in women with conditions that cause fat malabsorption (
Vitamin K - Vitamin K is important for bone and heart health and required for healthy blood clotting. Vitamin K deficiency can occur in women with certain genetic disorders and be caused by inadequate dietary intake or the use of certain medications (
Vitamins play many essential roles in the body. Depending on their age and health status, women have different needs for both fat- and water-soluble vitamins throughout their lifespan.
Nutrient needs differ throughout a woman’s life.
Deficiencies are also more common during certain life stages, such as pregnancy, and under certain circumstances, such as when a woman smokes or drinks excessively or is diagnosed with a medical condition.
Keep in mind that this article only focuses on vitamins, not all nutrients.
Children and teens
Girls ages 9 through 13 generally need smaller amounts of vitamins than older teens and women due to their smaller body size. However, teens over the age of 14 have vitamin needs similar to those of adults.
Research shows that teenage girls are more likely to become deficient in some nutrients than the general population. For example, teenage girls are at a greater risk of developing a deficiency in vitamin D and folate (
In less developed countries, vitamin A deficiency is also common among teenage girls (
Additionally, studies show that pregnant teens are more likely to not meet the intake recommendations for several nutrients, including vitamins E and D.
Women ages 19–50
Women of child-bearing age are more likely to be deficient in several vitamins, including vitamin D and B6.
A study that included data on over 15,000 people found that nutrient deficiency risk, including deficiencies in B6 and vitamin D, was most common in women ages 19–50 (
Pregnant and breastfeeding women
During pregnancy and breastfeeding, nutrient needs increase to support fetal and maternal health. Needs for nearly all water- and fat-soluble vitamins are higher during pregnancy and lactation.
For this reason, pregnant and breastfeeding women are at a greater risk of developing vitamin deficiencies (
What’s more, evidence suggests that the current recommendations for certain vitamins, including vitamin D, for pregnant women are too low.
Choline is another important nutrient for fetal and maternal health. Studies show that most pregnant women in the United States aren’t getting the recommended 450 mg per day of choline. Unfortunately, many prenatal vitamins do not contain choline (
Older adults often have inadequate dietary intakes and take medications that may reduce vitamin levels in the body, increasing their risk of developing one or more vitamin deficiencies.
Women who smoke or drink excessively are at a greater risk of developing vitamin deficiencies due to inadequate dietary vitamin intakes and malabsorption of vitamins.
Women with certain medical conditions, including type 2 diabetes, autoimmune diseases, and gastrointestinal conditions, are more likely to develop a deficiency in one or more vitamins than the general population.
Studies also show that women with obesity are at greater risk of vitamin deficiencies, including B12 and vitamin D (
Additionally, women who undergo bariatric surgery are significantly more likely to develop vitamin deficiencies (
African American women are more likely to be deficient in vitamin D, in part because they have higher concentrations of melanin (a skin pigment), which blocks the UVB sunlight needed to produce vitamin D in the skin (
Nutrient needs change throughout a woman’s life. Certain women are at greater risk of developing nutrient deficiencies due to factors like increased nutrient demands, inadequate dietary intake, malabsorption, and more.