Do I Really Need A Dietary Supplement?
Many of us have been vaguely aware of our nutritional needs since the days of hunting for crossword puzzles on cereal boxes. Even if we flipped past the nutrition facts on our quest to connect the dots, its formidable label reminded us our food met a need that could be neatly measured in black and white.
Despite the crisp, clean lines of nutritional labels, however, nutritional needs are far from straightforward. Our dietary needs can vary vastly from person to person and change throughout the course of our lives. In an ideal world, we would get all the vitamins and minerals we need from our food. Most of us know, however, that the reality is far more complicated than that.
Nutritional needs are a moving target. Not only do they vary from person to person, but they also continue to shift and change throughout our lives. Everyone is different. So before we really talk about whether or not we need a dietary supplement, we’ve got to define what “need” means.
A Quick Look at the Nutrients We're Missing
There’s a bare minimum amount of vitamins and minerals that every human needs in order to live, and the research shows most of us aren’t even hitting that. As many as 9 out of every 10 Americans are falling short of consuming adequate amounts of nutrients from their food alone.1
A survey conducted by the National Health and Nutrition Examination Survey (NHANES) found that most Americans do not meet their recommended intakes for many essential nutrients including: vitamins, A, C, D, and E as well as the minerals magnesium, potassium, and calcium.2,3
Those recommended intakes are referred to as RDAs or recommended dietary allowances and for many nutrients they’re already set pretty low. Yet still many Americans aren’t meeting even those minimum standards.2 The space between these minimum standards and the amounts we’re consuming is referred to as a “nutrient gap” or shortfall, and the gaps for some nutrients are so widespread they’ve been deemed a public health concern.
Dietary supplements, such as personalized multivitamins, are meant to help bridge that gap. They’re a convenient and affordable way to ensure we’re getting the nutrients we need no matter what life throws at us. But before we start stocking our cupboards, let’s take a quick look at the recommended dietary intake for both men and women ages 19–70.
Your Nutrients and You: RDAs for Adults Ages 19-70
RDAs are guidelines to sustain our life, but they don’t always take into account factors that promote our optimal health. Plus a host of factors such as our dietary habits and lifestyle choices can all affect how well our body absorbs or metabolizes certain nutrients. That said, RDAs can provide a helpful insight into whether or not we’re even meeting the bare minimum requirements for our health.
A Quick Note Regarding Gender and RDAs
The Institute of Medicine lists RDAs by age and gender.4 These gender differentiations, however, are partly determined by body weight (with a few notable exceptions for iron RDAs during menstruation, pregnancy, lactation, and menopause). It’s best to evaluate your needs on an individual basis taking into account your personal habits, dietary restrictions, and life stages.
Vitamins make up almost half of the micronutrients we need to live, and are usually the first type of nutrient that comes to mind when we’re talking about dietary supplements. They’re divided into fat-soluble and water-soluble and play different roles in our body.5
Vitamin A is fat soluble and best known for its critical role in healthy eye function, though it supports a healthy immune system as well.
- Women need 700mcg/day, which can be found in many foods including:
- 1 cup of cooked kale
- 1 medium sized cantaloupe
- Men need 900mg/day, which can be found in many foods including:
- 1 baked sweet potato
- 1 cup of cooked spinach
Vitamin B1 (Thiamin)
Thiamin like all the other vitamin Bs plays a key role in cellular energy production and is a major player in the nervous system.
- Women need 1.1mg/day, which can be found in many foods including:
- 1 slice of whole wheat bread
- 1 cup of milk
- 1 orange
- ½ of one cantaloupe
- Men need 1.2mg/day, which can be found in many foods including:
- 2 slices of whole wheat bread
- 1 ounce of pecans
- ½ cup of cooked, boiled green peas
Vitamin B2 (Riboflavin)
Riboflavin helps generate cellular energy as well, specifically by helping to metabolize carbohydrates.
- Women need 1.1mg/day, which can be found in many foods including:
- 1 ounce of cheddar cheese
- 3 ounces of cooked salmon
- ½ cup of boiled broccoli
- Men need 1.3mg/day, which can be found in many foods including:
- 1 ounce of almonds
- 6 ounces of roasted dark meat chicken
Vitamin B3 (Niacin)
Niacin supports more than 400 metabolic pathways in the body, which is more than any other B vitamin.
- Women need 14mg/day, which can be found in many foods including:
- 5 ounces of cooked salmon
- ¾ cup of fortified cereal
- 5 ounces of light canned tuna packed in water
- Men need 16mg/day, which can be found in many foods including:
- 6 ounces of cooked salmon
- ¾ cup of fortified cereal
- 6 ounces of light canned tuna packed in water
Vitamin B5 (Pantothenic Acid)
Vitamin B5 is essential to cellular energy production like all other B vitamins, but is also useful when breaking down fats and helping to make hormones and neurotransmitters.
- Women and men need at least 5mg/day, which can be found in many foods including:
- 2 raw California avocados
- 2 ½ cups of cooked sweet potato with skin
- 2 ½ ounces of sunflower seed kernels
- 3 ounces of beef liver
Vitamin B6 assists in over 100 different protein processes in the body, as well as helping to support red blood cell formation (an important means of transporting oxygen throughout our bodies).
- Women ages 19–50 need 1.1mg/day, which can be found in many foods including:
- 6 ounces of light cooked chicken meat without skin
- 2 medium russet baked russet potatoes with skin
- 2 medium avocados
- Men ages 19–50 need 1.3mg/day which can be found in many foods including:
- 3 medium bananas
- 3 cups of cooked spinach
- 6 ounces of light cooked turkey meat
- Women over 51 need 1.5mg/day, which can be found in many foods including:
- 1 cup of fortified cereal (quantities vary by cereal)
- 6 ounces of wild cooked salmon
- Men over 51 need 1.7mg/day, which can be found in many foods including:
- 1 cup of fortified cereal (quantities vary by cereal)
- 6 ounces of wild cooked salmon
Vitamin B7 (Biotin)
Vitamin B7 is involved in dozens of cellular reactions, including those which turn the food we eat into the fuel our cells need to function. Many foods contain some biotin, but how much they contain can vary. For instance, plant variety and season can affect the biotin content in cereal grains, while certain processing techniques (like canning), can reduce the biotin content in foods.
- Women and men need at least 30 mcg/day, which can be found in many foods including:
- 1–1½ large cooked eggs
- 3 ounces of cooked liver
Vitamin B9 (Folate)
Vitamin B9 (folate and folic acid) plays a crucial role in making DNA. It’s probably best known for its role in the brain and nervous system developments in fetuses and babies, but vitamin B9 is also essential for brain function at all ages.
- Women and men need at least 400mg/day, which can be found in many foods including:
- 1 ½ cups of cooked, boiled lentils
- 2 ½ cups of enriched, cooked spaghetti
- Women who are pregnant need at least 600mg/day, which can be found in many foods including:
- 4 cups of enriched, cooked white rice
- 4 ½ cooked, boiled spinach
- Women who are lactating need at least 500mg/day, which can be found in many foods including:
- 3 ½ cups of cooked, boiled garbanzo beans
- 42 spears of asparagus
Making A B-line for Vitamin B9
As you can see, some of these nutrients are easier to get from our food on a daily basis than others. That’s why most doctors recommend B9 dietary supplements for women who are lactating, pregnant, or looking to get pregnant soon.
Vitamin B12 (cobalamin) is a critical part of red blood cell formation, which helps to transport oxygen throughout the body, and it’s required for proper nerve function. Unlike the other water-soluble vitamins, B12 can be stored in the liver for 3–5 years, although it is still important to get B12 on a regular basis.
- Women and men need at least 2.4mcg/day, which can be found in many foods including:
- 3 ounces of dry-heat cooked salmon
- 1 ounce of lean, plate steak, cooked, grilled beef
- 2 cups of skim milk
Vitamin C is an antioxidant best known for its ability to support immune health.
- Women need at least 75mg/day, which can be found in many foods including:
- ¾ cup of raw orange juice
- 1 cup of cooked brussel sprouts
- Men need at least 90mg/day, which can be found in many foods including:
- 1 medium raw grapefruit
- 1 cup cooked broccoli
Otherwise known as the “sunshine vitamin,” this nutrient is best consumed through our skin. Spending 10–15 minutes in the sun a few times every week should provide us with most of the vitamin D we need. There are a lot of factors—like cloud coverage, sunscreen, and even pollution—that can interfere with our body’s ability to generate enough of this essential nutrient even in the sunniest circumstances.
- Women and men need at least 15 mcg/day, which can be found in some foods including:
- 4 ounces of pink canned salmon
- 6 cups of orange juice or milk fortified with vitamin D
There are actually eight forms of vitamin E which occur naturally in plant-based foods. We’re listing the α-tocopherol form here as its one of the richest and most bioavailable forms of vitamin E.
- Women and men need at least 15mg/day, which can be found in some foods including:
- 7 ½ tablespoons of olive oil
- 2 ounces of almonds
- 2 ounces of sunflower seeds
- 5 tablespoons of smooth peanut butter
With daily amounts like these, it’s no wonder vitamin E was deemed an underconsumed nutrient in American diets.3
Vitamin K comes in two forms, K1 and K2, which are important for blood clotting, and working with calcium to support healthy bones.
- Women need 90mcg/day, which can be found in some foods including:
- 2 cups shredded, green, raw leaf lettuce
- 9 tablespoons of canola oil
- ¾ cup of raw spinach
- Men need 120 mcg/day, which can be found in some foods including:
- ½ cup of raw swiss chard
- ¼ cup of raw kale
- ½ cup chopped broccoli
It’s worth mentioning again here that these RDAs are based on the minimal levels to prevent deficiencies and not on the amounts that benefit our best health.
Dietary supplements can offer other nutrients as well that still play an important role in our overall health. Here are a few others worth looking at:
In its 2015–2020 report, the DGA declared dietary fiber as a “nutrient of public health concern.”3 Like other nutrient shortfalls with this title, that’s because the long-term health impacts of not getting enough of it.6
- Women ages 19–50 need at least 25g/day, which can be found in many foods including:
- 2 ½ cups cooked artichoke hearts
- 1 ¾ cups cooked, boiled lentils
- 3 cups oats
- Women over age 50 need at least 21g/day, which can be found in many foods including:
- 2 ½ cups instant oatmeal cereal
- 2 cups fresh raspberries
- 2 cups fresh guava
- Men ages 19–50 need at least 38g/day, which can be found in many foods including:
- 1 cup all-bran wheat cereal
- 1 ½ cups cooked, boiled navy beans
- 3 cups uncooked, pitted, dried plums (prunes)
- Men over age 50 need at least 30g/day, which can be found in many foods including:
- 6 cups cooked quinoa
- 5 cups cooked, baked, winter butternut squash
- 2 ½ cup canned refried beans
While choline isn’t technically considered a vitamin, it’s an essential nutrient. It’s one of the lesser known nutrients but is recognized by the DGA as a nutrient of concern due to most of us not meeting recommended intake.3 If you don’t consume meat, milk, or eggs you’re at risk of an inadequate choline intake.6
- Women ages 19–70 need at least 425mg/day, but that number goes up to 450mg/day while pregnant. These RDAs can be found in some foods including:
- 12 ounces of scallops
- 28 ounces of peanuts
- 6 ¾ cups of cooked, boiled brussel sprouts
- Women who are lactating and men ages 19–50 both need at least 550mg/day, which can be found in many foods including:
- 3 ¾ large eggs
- 8 ¾ cups of broccoli
- 2 ¾ cups toasted wheat germ
Similar to vitamin B9, choline’s RDAs are rather difficult to obtain from our everyday diets. Despite that, it’s still a crucial nutrient that everyone needs to implement into their diets regardless of their stage of life.
EPA and DHA Omega 3 Fatty Acids
We don’t have RDAs for these omega 3 fatty acids yet, but we do know they are important structural components of cell membranes and are critical for many functions in the body. Both EPA and DHA support heart health—with DHA being important for brain health, and EPA helping to support a healthy mood.7
The American Heart Association recommends eating 2 servings of fish (particularly fatty fish) per week.8 The 2015–2020 Dietary Guidelines for Americans recommend 8–12 ounces per week, which provides about 250mg/day of EPA/DHA.3 Unfortunately, most Americans consume less than 1/2 ounce per week, which provides only roughly 85 mg EPA/DHA/day.9
Good sources of omega 3 fatty acids (3 ½ ounces twice per week) are salmon, mackerel, herring, lake trout, sardines, and albacore tuna.8
When we talk about supplements, most people immediately think of vitamins. But minerals are essential nutrients as well and play just as many vital roles in our overall health and well being. Minerals are inorganic compounds found in our soil and sometimes in our water, they’re passed through plants and animals and eventually onto us.
Living organisms (like us) can’t make vitamins or minerals on their own. Which is a bummer, considering minerals are involved in forming and maintaining our bones and teeth, used to make up our body fluids and tissues, and help with normal nerve function. Given their important roles in our health and their tendency to be overlooked, these powerful nutrients deserve a breakout section of their own.10
Calcium is the most abundant mineral in the body and is essential for a host of vital functions. It helps with muscle function, nerve transmission, and (when teamed up with vitamin D plus a well-balanced diet), calcium may even help reduce the risk of osteoporosis.
- Women ages 19–50 and men ages 19–70 need 1000mg/day, which can be found in some foods including:
- 3 cups of milk
- 5 ounces of cheddar cheese
- 1 cup of raw tofu prepared with calcium sulfate
- Women over age 50 need at least 1200mg/day, which can be found in some foods including:
- 2 cups of plain, low-fat yogurt
- 4 cups of milk
- 12 cups of cooked kale
With daily intakes like these, it’s easy to see why this calcium’s nutrient gap is so large that this mineral was deemed a “nutrient of public concern.” 3
Chromium helps support healthy blood sugar, as it’s necessary for both the metabolization and utilization of carbohydrates (aka the yummiest of foods).
- Women ages 19–50 need 25 mcg/day, which can be found in some foods including:
- 3 ¼ cups of grape juice
- 7 English muffins
- Men ages 19–50 need at least 35mcg/day, which can be found in some foods including:
- 1 ½ cups of broccoli
- 5 ounces of beef
- Women over age 50 need at least 20mcg/day, which can be found in some foods including:
- 1 cup of broccoli
- 3 waffles
- 6 ounces of processed turkey ham
- Men over age 50 need at least 30mcg/day, which can be found in some foods including:
- 9 ounces of processed turkey ham
- 11 cups of mashed potatoes
- 2 ¾ cups of broccoli
Who Doesn't Love A Whole-Grain Waffle?
While foods are our best source of vitamins and minerals, it can be difficult to consume the quantities required to get enough of one nutrient (like chromium). There are other factors to consider as well, like how whole-grain waffles may be a great source of chromium but are often dosed in sweet syrups. It’s a lot to think about. Maybe we need to waffle to snack on while chewing it over.
Copper is involved in a lot of important functions ranging from iron metabolism and gene regulation to helping maintain connective tissues. It’s also involved in immune system functions and helps make antioxidant enzymes in our body.
- Women and men need at least 900mcg/day, which can be found in many foods including:
- 3 ounces of cooked Alaskan king crab meat
- 2 ounces of dry roasted hazelnuts
- 4 cups of white raw mushrooms
Our thyroid hormones produce this famous mineral found in many table salts. Iodine is important during every stage of life, but especially critical for fetus and infant development.
- Women and men need at least 150mcg/day, which can be found in some foods including:
- 2 grams of iodized salt
- 1 ½ cups of cow milk
- 2 ½ baked potatoes with skin
Iron helps make our red blood cells, and is an essential part of the many proteins and enzymes required to support a range of bodily functions. There are two types of iron, heme and nonheme, both of which are found in different food sources. Other nutrients can also impact how each type of iron is absorbed, so it’s important to take a look at your whole diet when considering the best sources of iron.
- Women ages 19–50 need 18mg/day, which can be found in many foods including:
- 1 cup of raisin bran cereal (check label for specifics)
- 3 cups of cooked spinach
- 3 cups of cooked lentils
- 11 ounces of beef
- 9 medium cooked pacific oysters
- Women over age 50 and men ages 19–70 need only 8mg/day, which can be found in some foods including:
- 4 ounces of cashews
- 2 ¾ cups of cooked quinoa
- ¾ cup of regular raw tofu
- 4 medium sized baked potatoes with the skin
Red Meat, Please!
Iron RDAs nearly double during a woman’s childbearing years, and can be even higher during pregnancy or for women with heavier period flows. Menstruating can cause extra iron loss, so those cliché monthly red meat cravings might be there for a reason! Thankfully, there are food options outside of having to eat a 12 ounce steak every month.
Magnesium is a major player in cellular energy, but it’s also listed as one of many underconsumed nutrients in the United States. Considering magnesium is involved in over 300 reactions in the body, however, this multitasking mineral might well deserve a side dish of its own.
- Women ages 19–30 need at least 310mg/day, and women ages 31–70 need at least 320mg/day, which can be found in some foods including:
- 3 ounces of brazil nuts
- 5 ½ avocados
- 3 ¾ cups of medium-grain cooked brown rice
- Men need at least 420mg/day, which can be found in some foods including:
- 5 ½ ounces of almonds
- 2 ½ cups of frozen, chopped, cooked spinach
- 14 shredded wheat biscuits
Manganese is required to help with healthy bone development, as well as making and breaking down glucose and antioxidant enzymes.
- Women need at least 1.8mg/day, which can be found in some foods including:
- 1 cup of green tea
- 1 ¼ cups of raw pineapple
- 1 ¼ cup cooked spinach
- Men need at least 2.3mg/day, which can be found in some foods including:
- 2 ½ cups of cooked sweet potato
- 4 slices of whole wheat bread
- 1 ¼ cup cooked brown rice
Molybdenum is worth noting despite the fact that the typical American diet provides more than enough of it. Molybdenum is a trace mineral which—through its vital role in the activation of certain enzymes—also helps to remove damaging substances from the body. It also aids in the metabolism of nucleic acids (the building blocks of DNA).
Phosphorus is found in every single one of our cells and is responsible for helping body tissues grow and repair themselves. It’s found in most food with dairy, and is especially abundant in cereal, meat, and fish.
- Women and men need at least 700mg/day, which can be found in some foods including:
- 7 ounces of cooked chinook salmon
- 2 ounces of plain nonfat yogurt
- 2 cups of cooked lentils
This trace mineral is essential for thyroid hormone metabolism. It also helps protect us from free radical damage by assisting the many powerful antioxidant enzymes already found in our bodies. Selenium content in foods is heavily dependent on the soil (as with all minerals) in which the food is grown. Organ meats and seafood are two of its richest food sources.
- Women and men need at least 55mcg/day, which can be found in some foods including:
- 7 ounces of light-meat, cooked, roasted chicken
- 4 ounces of cooked, steamed shrimp
- ¾ cups of dried sunflower seed kernels
Zinc is a trace mineral which plays a central role for many body functions, including being essential in maintaining immune system integrity.
- Women need at least 8mg/day, which can be found in some foods including:
- 4–5 ounces of chuck, blade roast, cooked beef
- 2 cups of fortified, whole-grain toasted oat cereal
- 9 ounces of pork, loin, blade roast, cooked
- Men need at least 11mg/day, which can be found in some foods including:
- 6 ounces of chuck, blade roast, cooked beef
- 3 cups of dry roasted soy beans
- 12 ounces of roasting, dark meat cooked chicken
Potassium was recognized as a “nutrient of public health” concern as well due to the vast numbers of Americans consuming well under the RDAs.3
- Women and men need at least 4.7g/day (or 4700mg), which can be found in some foods including:
- 11 bananas
- 6 cups of boiled, cooked green beets
- 5 medium baked potatoes with skin
Level With Your Limitations
Vitamins and minerals also have what’s known as a “tolerable upper intake level” or UL which is established by the Institute of Medicine of The National Academies. The UL is the maximum daily intake unlikely to cause adverse health effects in healthy individuals, or the highest dose used in studies without side effects.4 We won’t list them all here, but if you’re super interested in supplements, you’ll want to get familiar with your ULs as well as your recommended intakes.
You've Got a Friend in Dietary Supplements
It’s hard enough dealing with everything else life throws at us, the last thing we want to do is count our RDAs like calories. The data shows, however, that these nutrient shortfalls are no joke. Vitamins and minerals are called “essential” nutrients for a reason and leaving them out of our diets on a regular basis will have serious impacts on our health and happiness.
Thankfully, there are steps we can take every day to address this. Upgrading our food game is the best (and tastiest) way of ensuring our bodies get what they need. But for the days when cooking the world’s most well-rounded meal seems out of reach, or when the kids make a mess right before bed—dietary supplements are there to help. They’re no substitute for the real thing, but they can make sure we’re getting the nutrients we might otherwise be missing from our diets. Now, where’s that waffle…?
This information is only for educational purposes and is not medical advice or intended as a recommendation of any specific products. Consult your health care provider for more information.
- Wallace, TC et al. Multivitamin/mineral supplement contribution to micronutrient intakes in the Unites States. 2007-2010. J Am Coll Nutr. 2014;33(2):94-102. https://www.ncbi.nlm.nih.gov/pubmed/24724766
- Fulgoni VL, 3rd et al. Foods, fortificants, and supplements: Where do Americans get their nutrients? J Nutr. 2011; 141 (10): 1847-1854. https://www.ncbi.nlm.nih.gov/pubmed/21865568
- U.S. Department of Health and Human Services. “2015–2020 Dietary Guidelines for Americans.” 2015. 8th ed. U.S. Department of Agriculture. Accessed on: September 5, 2019. http://health.gov/dietaryguidelines/2015/guidelines/
- U.S. Department of Health and Human Services. “Nutrient Recommendations: Dietary Reference Intakes (DRI).” National Institutes of Health, Office of Dietary Supplements. Accessed on: October 31, 2019. https://ods.od.nih.gov/Health_Information/Dietary_Reference_Intakes.aspx
- Oregon State University. “Vitamins.” 2016. Linus Pauling Institute, Micronutrient Information Center. Accessed on: October 9, 2019. https://lpi.oregonstate.edu/mic/vitamins
- Oregon State University. “Other Nutrients.” 2015. Linus Pauling Institute, Micronutrient Information Center. Accessed on: October 9, 2019. https://lpi.oregonstate.edu/mic/other-nutrients
- Larrieu, T et al. Relevance of Nutritional Omega-3 Fatty Acids for Depression and Anxiety. Front Physiol. 2018 Aug 6;9:1047. https://www.ncbi.nlm.nih.gov/pubmed/30127751
- American Heart Association. “Keep saying yes to fish twice a week for heart health.” 2018.
American Heart Association Scientific Advisory. https://newsroom.heart.org/news/keep-saying-yes-to-fish-twice-a-week-for-heart-health
- Papanikolaou, Y et al. U.S. adults are not meeting recommended levels for fish and omega-3 fatty acid intake: results of an analysis using observational data from NHANES 2003-2008 Nutr J. 2014;13:31. https://www.ncbi.nlm.nih.gov/pubmed/24694001
- Oregon State University. “Minerals.” 2016. Linus Pauling Institute, Micronutrient Information Center. Accessed on: October 9, 2019. https://lpi.oregonstate.edu/mic/minerals