Dietary Supplements: Vitamins 
            and Minerals
            Fact Sheet No. 9.338                                           Food and Nutrition Series|Health
            by L. Bellows, R. Moore, A. Gross*
                 The current food environment can                          (CAM). It is important to remember that                            Quick Facts
            be complicated, given the multitude of                         supplements are not required to go through 
            choices and purchasing options available                       the same stringent testing as over the counter                     •	Most	individuals	can	
            for consumers. Many individuals are left                       (OTC) and prescribed medicine, and are not                            obtain	all	the	vitamins	and	
            questioning the best way to obtain vitamins                    regulated as closely by the Food and Drug                             minerals	needed	to	meet	
            and minerals, as a variety of options                          Administration (FDA).                                                 the	recommended	dietary	
            are available- including whole foods,                                                                                                allowances	and	adequate	
            multivitamins and multiminerals, as well                       Choose Food First,                                                    intakes	by	eating	a	variety	of	
            as individual dietary supplements. The                         Supplements Second                                                    foods.
            incredible variety of dietary supplements 
            available in today’s market comprises a wide                       Vitamin and mineral supplements are                            •	Dietary	supplements,	
            range of brand names, supplement forms                         the most common dietary supplement used                               including	multivitamins	
            (pill, powder), and amounts (10 to 100 times                   by approximately 40% of adults and 30% of                             and	multiminerals,	do	not	
            the daily recommended intake value), which                     children in the United States. Despite the                            guarantee	protection	against	
            can make purchasing supplements very                           popularity of supplements, many individuals                           disease.
            confusing. The following information defines                   are capable of obtaining all of the required 
            dietary supplements and helps to explain the                   vitamins and minerals through a healthy                            •	Large	doses	of	either	single	
            value of food in comparison to vitamin and                     diet alone. In fact, those who consume a                              nutrient	supplements	or	
            mineral supplements. General guidelines are                    multivitamin or multimineral on a daily                               high	potency	vitamin	and	
            also provided to help individuals choose an                    basis may be at risk for excessive intake, or                         mineral	combinations	may	be	
            appropriate supplement to fit their needs,                     toxicity of certain nutrients. Additionally,                          harmful.
            as well as recommendations for obtaining                       supplements can be very expensive—as 
            important nutrients from diet alone. For                       evidenced by the $30 billion that Americans                        •	Although	vitamin	deficiency	
            more information on herbal supplements, see                    spend annually on all forms, a number                                 is	rare,	it	may	occur	when	
            fact sheet Dietary Supplements: Herbals and                    that continues to grow every year. In some                            nutrients	are	limited	in	one’s	
            Botanicals.                                                    circumstances a daily supplement may not                              diet,	or	as	a	result	of	a	
                                                                           be necessary, and for many, consuming a                               secondary	deficiency	caused	
            What are Dietary                                               multivitamin or multimineral once every                               by	tobacco,	alcohol	use,	or	
            Supplements?                                                   2 to 3 days may be a cost-effective choice.                           disease.
                                                                           Since the body has limited storage for many 
                 Dietary supplements include vitamins,                     of these nutrients, most of the time they are                      •	Consult	a	medical	
            minerals, herbs, amino acids, enzymes, and                     simply excreted. Essentially, the most cost-                          professional	before	taking	any	
            other substances that may be “supplemented,”                   effective way to promote good health is eat a                         self-prescribed	single	nutrient	
            or added to a diet, in order to complete                       wide selection of foods and exercise regularly.                       supplements.
            dietary needs or to make up for a nutrition                    For a better understanding of how to choose 
            deficiency—they are not intended to replace                    foods that provide the daily requirements 
            a healthy diet. Dietary supplements may                        for nutrients see the USDA websites: 
            be found in many forms, including pills,                       Choose MyPlate or The Dietary Guidelines 
            capsules, powders, drinks, or energy bars.                     for Americans. See Table 1 for common 
            Supplement use can also be considered a type                   myths associated with vitamin and mineral 
            of complementary or alternative medicine                       supplements.
                                                                                                                                              ©	Colorado	State	University	
                                                                                                                                              Extension.	12/98.	Revised	9/13.
                                                                                                                                              www.ext.colostate.edu
            *L. Bellows, Colorado State University Extension food and 
            nutrition specialist and assistant professor; R. Moore, 
            graduate student; A. Gross, undergraduate student. 
            9/2013
             Who Should Consider a                                                    How Are Dietary                                          nutrient. Those who do not consume 
             Multivitamin, Multimineral,                                                                                                       these food items and do not receive 
             or Individual Nutrient                                                      Supplements                                           exposure to regular sunlight should 
             Supplements?                                                                  Regulated?                                          consider a vitamin D supplement. 
                                                                                                                                         •	    Calcium is mostly found in dairy 
                 National food consumption data and                           In	1994	Congress	passed	the	Dietary	                             products, therefore vegans and 
             dietary surveys show that the majority of                        Supplement	Health	and	Education	                                 vegetarians who do not consume dairy 
             Americans consume all of the nutrients                           Act	(DSHEA),	which	clearly	defines	                              may not receive enough calcium in 
             needed, through a balanced and varied                            supplements	as	food,	not	drugs.	                                 their diet. 
             diet that includes healthy food choices.                         Unlike	drugs,	supplements	do	not	                          •	    Iron is found in two different forms—
             Some nutrients, like calcium and iron, may                       need	FDA	approval	before	being	                                  heme iron (from animal products) 
             require careful food selection, but can be                       marketed	and	sold	to	the	public.	                                is more available for absorption, and 
             obtained from adequate consumption of a                          The	supplement	manufacturer	is	                                  nonheme iron (from plant foods) 
             variety of foods. Certain individuals may                        responsible	for	the	safe	consumption	                            is less available for absorption. 
             have dietary restrictions (such as those with                    of	supplements	and	providing	                                    Vegetarians and vegans may receive 
             celiac disease or lactose intolerance), or                       evidence	to	support	health	claims.		                             enough iron from their diet, although 
             belong to a particular life stage (pregnant,                                                                                      if it is strictly from plant foods 
             breastfeeding, or older adult) and may                           However,	evidence	does	not	have	to	                              (nonheme sources), twice as much 
             benefit from taking specific supplements.                        be	provided	before	the	supplement	                               dietary iron each day may be needed.
             Consult a medical professional before                            is	marketed,	and	the	FDA	will	take	                        •	    Zinc is primarily found in animal 
             deciding to take a dietary supplement. See                       action	against	any	unsafe	dietary	                               proteins, therefore vegetarians 
             Table 2 for recommendations for the type                         supplements	after	they	reach	the	                                and vegans may require 50% more 
             and amount of supplement that may be                             market.		In	2007	the	FDA	implemented	                            zinc in the diet than is generally 
             best, and Table 3 for a description of how to                    the	Current	Good	Manufacturing	                                  recommended. Additionally, beans 
             obtain important nutrients through food.                         Practices	(CGMPs),	which	act	to	                                 and grains have compounds that 
             Pregnant women or women who may                                  insure	the	consistency,	identity,	purity,	                       may keep zinc from being absorbed 
             become pregnant: This population is                              strength,	and	composition,	of	dietary	                           as readily. For more information 
             strongly advised to consume supplements                          supplements.                                                     regarding dietary recommendations 
             for folic acid (folate), iron, or a prenatal                                                                                      for vegetarians and vegans, see fact 
             vitamin that contains these nutrients.                           Before	consuming	any	type	of	                                    sheet Vegetarian Diets. 
             •	    Folic Acid helps to prevent birth                          supplement,	consult	a	medical	                             Women with heavy menstrual bleeding: 
                   defects of the brain and spine, and may                    professional	and	research	the	                             This population should consume extra iron, 
                   be obtained through fortified foods                        supplement	thoroughly.	                                    which acts to replace that which is lost due 
                   (such as enriched breads and cereals),                     The	following	website	resources	                           to blood loss.
                   vitamin supplements, or a combination                                                                                 Those with a restrictive diet (1,600 
                   of both.                                                   are	provided	to	help	one	make	                             calories per day or less): For most 
             •	    Iron helps to increase the amount                          an	educated	decision	and	identify	                         adults, a diet that includes less than 1,600 
                   of blood in the body and helps keep                        inaccurate	information	when	choosing	                      calories per day will not supply all of the 
                   blood healthy. Too iron little may lead                    a	dietary	supplement:                                      necessary vitamins and nutrients to meet 
                   to anemia.                                                       National	Library	of	Medicine	                        the body’s needs—and these individuals 
             •	    A prenatal vitamin may contain both                              (NLM)–Dietary	Supplements	                           should consume a multivitamin and/
                   folic acid and iron, as well as other                                                                                 or multimineral supplement. Consult a 
                   important vitamins and minerals both                             Labels	Database	                                     medical professional regarding type and 
                   mother and baby need for proper                                  CSU	Extension	fact	sheet,	                           recommended amount of supplement.
                   nutrition (for example, vitamin                                  Nutrition Misinformation: How to                     Older adults (50+), menopausal, 
                   B12 is important if the mother is a                              Identify Fraud and Misleading                        and postmenopausal women: These 
                   vegetarian). Some nutrients, however,                            Claims                                               individuals should consume vitamin B12, 
                   may be harmful to babies (such as                                                                                     calcium, and a vitamin D supplement. 
                   vitamin A, where too much can                                                                                         Vitamin B12, calcium, and vitamin D, work 
                   cause birth defects), and a prenatal                                                                                  together to maintain healthy bones and 
                   supplement ensures that both mother                           Vegans and strict vegetarians that do                   reduce the risk for fractures.
                   and child are receiving healthy doses of                      not consume eggs or dairy products                      •	    Vitamin B12 is absorbed less readily 
                   all nutrients.                                                should consider taking a vitamin B12                          from foods as one ages. These 
             Vegetarians and vegans: This population                             supplement.                                                   individuals should receive vitamin 
             should ensure adequate intake of vitamin                      •	    Vitamin D is found in very few food                           B12 from fortified foods such as 
             B12, vitamin D, calcium, iron, and zinc.                            items, although dairy products, milk                          breakfast cereals, or through a dietary 
             •	    Vitamin B12 (cobalamin) is only                               alternatives (soy or almond milk),                            supplement.
                   found naturally in foods of animal                            orange juice, breakfast cereals, and                    •	    Calcium may not be absorbed as well 
                   origin such as eggs and dairy products.                       eggs, may be fortified with this                              in older adults and this population 
               may experience bone loss. A                  Misinformation: How to Identify Fraud and             Additional Resources
               combination of calcium intake from           Misleading Claims.  
               both food sources and supplemental              The term natural on a supplement                For	more	information	on	mineral	
               form is important.                           is not synonymous with safe. Several               recommendations	for	age	and	life	
          •	   Vitamin D is not produced as                 natural products may cause negative                stage,	see	the	National	Institutes	
               efficiently in older adults upon             drug interactions, worsen certain health           of	Health	(NIH)	Office	of	Dietary	
               exposure to sunlight. Additionally, the      conditions, and may be harmful at higher 
               ability of the kidney to convert vitamin     doses. Do not take a supplement prior              Supplements	website–Vitamin	and	
               D to a form that the body can use is         to taking prescription medications,                Mineral	fact	sheet.
               also dampened with age.                      or receiving advice from a medical                 For	more	information	on	how	to	spot	
          Breastfed and partially breastfed infants:        professional. Before choosing to take a            a	false	health	claim,	see	the	Federal	
          Since human milk is a poor source of              dietary supplement, consider whether               Trade	Commission	(FTC)	website.
          vitamin D, infants who are solely breastfed       the supplement is necessary, and possible 
          or drink less than 1 quart per day of             dietary modifications that might be a better       For	information	on	recent	supplement	
          vitamin D-fortified formula or milk should        option (Table 3).                                  alerts	and	safety	information,	see	the	
          receive a supplemental form of vitamin D.                                                            Food	and	Drug	Administration	(FDA)	
          Limited milk intake and sunlight                  Do Vitamin and Mineral                             website.	
          exposure: Dairy products and sunlight             Supplements Pose a 
          exposure are two primary means of                 Health Risk?
          obtaining vitamin D, therefore if either             Large doses of either single-nutrient              research shows that vitamin B-6 
          is limited, a supplemental form may be            supplements or high potency vitamin-                  can cause nerve damage at the high 
          necessary.                                        mineral combinations may be harmful.                  doses prescribed for pre-menstrual 
          Health conditions that may limit nutrient         These megavitamins may contain 10 to                  syndrome (PMS). High intakes of folic 
          use and absorption: Those with health             over 100 times the Dietary Reference Intake           acid can mask or worsen the symptoms 
          conditions that may affect digestion,             (DRI) for a vitamin or mineral and can act            associated with a vitamin B-12 
          appetite, and limit nutrient absorption,          like drugs with potentially serious results.          deficiency. Large amounts of vitamin C 
          may not be receiving adequate nutrients           Very high doses of many supplements,                  can cause diarrhea and nausea. 
          from diet alone (examples include those           especially vitamins A, D, C, and B6, can         •	   Many factors influence toxicity. 
          with food allergies, physical trauma, and         cause serious health problems if taken                Supplement potency, dose (number 
          gluten intolerance).These populations             regularly. Excess of one nutrient may cause           and frequency), body size, and how 
          should consider a multivitamin and/               nutritional imbalances or increase the need           long the supplement is taken, all 
          or multimineral supplement.  Consult a            for other nutrients. Severe side effects such         influence whether a supplement can 
          medical professional regarding the type and       as kidney stones, liver or nerve damage,              be toxic. 
          recommended amount of supplement.                 birth defects, and even death can occur              For more information, see fact sheet 
                                                            from 10 to over 100 times of the DRI.            Water-Soluble Vitamins: B-Complex and 
          How to Choose a                                   •	  Taken in high amounts, some                  Vitamin C, and Fat-Soluble Vitamins: A, D, 
          Supplement                                            supplements may produce undesirable          E, and K.
              It is important for healthy individuals           effects such as fatigue, diarrhea and 
          who take vitamin or mineral supplements               hair loss.                                   Summary
          to limit the potency to 100% or less of           •	  Others may cause more severe side                With the increased availability and wide 
          the Dietary Reference Intake (DRI) for                effects such as kidney stones, liver or      variety of food accessible to consumers 
          their age, gender, and life stage (Table 2).          nerve damage, birth defects, or even         in the United States, most individuals can 
          Consuming a supplement that contains                  death. At high levels, single-nutrient       receive all of the vitamins and minerals 
          no more than 100% of the Daily Value                  supplements function as a drug in the        needed from food alone—this unique 
          (DV) is usually considered safe. High                 body and not as a nutrient.                  balance cannot be duplicated by taking 
          potency supplements that contain more             •	  Fat-soluble vitamins such as vitamins        any combination of supplements.  Certain 
          than 100% of the DV are not suggested.                A and D are harmful in high doses. For       individuals that have dietary restrictions, 
          Avoid supplements that provide mega                   non-smokers, supplements of vitamin          are pregnant or breastfeeding, older than 
          doses of any vitamins or minerals, or have            A should contain the majority of the         50, or with special dietary requirements, 
          added botanicals whose properties are                 vitamin in the beta-carotene rather          may need to supplement their diet with 
          unknown. Information about vitamin                    than the retinol form. Vitamin E may         a multivitamin and/or multimineral, or 
          and mineral content can be found on the               act as a blood thinner and should not        individual nutrient supplements.  Consult a 
          label of all dietary supplements. Be aware            be taken for at least one week prior to      medical professional for recommendations 
          of misleading claims that promise the                 surgery.                                     regarding the type and amount of 
          product is a “cure all” or can treat a disease.   •	  Water-soluble vitamins are commonly          supplement best for one’s individual needs.
          For more information on how to identify               thought of as harmless, however, 
          nutrition fraud, see fact sheet Nutrition 
            Table 1. Common myths and facts regarding dietary supplements.
              Myth                                   Fact                                                   Healthy Suggestion
              “Vitamin	and	mineral	                   Supplements	supply	only	a	fraction	of	the	             Food	contains	important	components	such	as	phytonutrients,	
              supplements	can	make	up	for	            nutrients	needed	daily,	and	are	not	a	quick	fix	       antioxidants,	fiber,	and	dietary	fat,	which	cannot	be	found	
              an	unhealthy	diet.”                     for	suboptimal	food	choices.		                         in	supplements.	Consuming	whole	foods	will	provide	these	
                                                                                                             components	naturally,	in	much	higher	levels.
              “Consuming	large	quantities	            The	body	will	only	use	the	vitamins	and	               Consult	a	doctor	or	dietitian	before	consuming	any	
              of	supplements	will	lead	to	            minerals	that	it	needs.	Any	extra	will	be	             supplement,	and	avoid	consuming	large	quantities	of	
              optimal	health.”                        excreted	or	may	pose	a	risk	for	toxicity.	             supplements.
                                                      Consuming	more	nutrients	than	the	body	
                                                      requires	does	not	give	added	energy,	
                                                      increased	brain	power,	or	greater	protection	
                                                      against	disease.
             “Supplements	with	added	                 The	body	makes	its’	own	digestive	enzymes	             Added	enzymes	are	unnecessary;	however,	consuming	
             enzymes	are	easier	to	digest.”           to	breakdown	and	absorb	supplements.                   lactase	enzymes	may	be	beneficial	for	those	who	are	lactose	
                                                                                                             intolerant.	
              “Timed-release	supplements	             Timed-release	supplements	are	costly	and	              Supplements	should	be	consumed	when	they	do	not	
              aid	in	absorption	throughout	           are	not	absorbed	throughout	the	day.                   compete	for	absorption	with	other	foods.		Consult	a	
              the	day.”                                                                                      medical	professional	regarding	the	type	and	combination	of	
                                                                                                             supplements	to	consume	at	certain	times	of	the	day.
              “More	expensive	vitamin	and	            The	cost	of	the	vitamin	does	not	necessarily	          Consider	purchasing	your	vitamins	from	well-known	retailers	
              mineral	supplements	are	worth	          translate	to	quality.	Generic	vitamins	are	            that	restock	frequently.
              the	extra	cost.”                        often	as	good	as	brand	names.	Vitamins	
                                                      and	minerals	are	commodity	items,	and	
                                                      every	manufacturer	has	access	to	the	same	
                                                      ingredients.	For	that	reason,	paying	more	
                                                      for	a	brand	name	won’t	necessarily	buy	
                                                      you	better	vitamins.	Also,	vitamins	lose	their	
                                                      potency	over	time	and	must	be	stored	at,	
                                                      or	below,	room	temperature.	If	bottles	are	
                                                      sitting	on	a	shelf	in	warm	room	or	in	direct	
                                                      sunlight,	they	may	degrade	even	before	their	
                                                      expiration	date.
              “Taking	supplements	that	               Antioxidant	supplements	do	not	offer	                  Consuming	foods	rich	in	antioxidants,	such	as	green	
              contain	antioxidants	such	as	           protection	against	cancer	or	heart	disease,	           vegetables,	citrus	fruits,	deep-orange	colored	produce,	and	
              vitamin	A,	E,	and	C	will	prevent	       and	may	even	do	some	harm.		Heart	                     other	fruits	and	vegetables	have	many	cancer	and	disease	
              cancer	and	heart	disease.”              disease,	cancer,	diabetes	and	high	blood	              fighting	properties.	
                                                      pressure	are	affected	by	many	factors,	one	of	
                                                      which	is	eating	patterns.	If	a	variety	of	foods	
                                                      are	consumed	in	adequate	and	moderate	
                                                      amounts,	supplements	are	unnecessary	and	
                                                      will	not	provide	added	protection.
              “Osteoporosis	can	be	                   Many	factors	such	as	calcium,	estrogen	                While	calcium	consumption	from	foods	such	as	milk	and	
              prevented	by	consuming	                 levels,	exercise,	gender,	body	size,	                  yogurt	is	the	best	way	to	meet	daily	needs,	a	daily	calcium	
              calcium	supplements.”	                  smoking,	race,	and	genes,	contribute	to	               supplement	with	vitamin	D	may	be	beneficial	if	calcium	intake	
                                                      the	development	of	osteoporosis.	The	most	             is	below	recommended	levels.
                                                      effective	treatment	in	postmenopausal	
                                                      women	may	be	a	combination	of	additional	
                                                      calcium,	vitamin	D,	exercise,	and	estrogen.	
              “Those	who	are	sick	or	                 Emotional	stress	does	not	increase	nutrient	           Individuals	who	are	sick	or	stressed	should	aim	for	a	healthful	
              stressed	will	benefit	from	             needs.	Physiological	stress	such	as	burns,	            balanced	diet	with	adequate	intake	of	all	recommended	
              vitamins.”                              trauma,	and	surgery,	do	increase	nutrient	             vitamins	and	nutrients.		Additionally,	research	shows	that	30	
                                                      needs,	and	a	supplement	may	be	prescribed.             minutes	of	exercise	for	5	days	out	of	the	week	is	an	important	
                                                                                                             part	of	a	healthy	lifestyle,	and	acts	to	combat	the	effects	of	
                                                                                                             stress	on	the	body.	
              “Those	who	smoke	or	consume	            Smoking	will	increase	the	body's	need	for	            Individuals	who	smoke	or	drink	alcohol	in	excess	should	speak	
              alcohol	in	excess	should	take	          vitamin	C,	and	alcohol	can	interfere	with	            to	a	medical	professional	who	will	provide	resources	to	help	one	
              vitamins	to	protect	their	body	         the	body's	ability	to	utilize	several	nutrients.	     discontinue	these	harmful	behaviors.		
              from	the	harmful	effects	of	            However,	taking	additional	vitamins	and	
              smoking	and	drinking.”                  minerals	will	not	protect	people	from	the	
                                                      harmful	effects	of	smoking	or	alcohol	abuse.