Do Dietary Supplements Actually Work – and Are They Safe?

Pro­tein-packed shakes that ​“taste like choco­late!”, fruit-fla­vored mul­ti­vi­t­a­min gum­mies, and bot­tle after bot­tle of vit­a­min tablets line the shelves of gro­cery stores. Shops ded­i­cat­ed to sell­ing every vit­a­min and min­er­al under the sun seem to have popped up everywhere. 

You’re not imag­in­ing things. Across the coun­try, dietary sup­ple­ment use is on the rise. Near­ly 75% of Amer­i­cans take at least one of the tens of thou­sands of dietary sup­ple­ments on the mar­ket, accord­ing to a 2023 Coun­cil for Respon­si­ble Nutri­tion (CRN)/IPSOS survey. 

Sup­ple­ments promise to give you essen­tial nutri­ents, help you sleep bet­ter, improve ath­let­ic per­for­mance, and sup­port your over­all health, with many claim­ing to be ​“all natural.”

Sounds great, right?

Well, you know the say­ing: If some­thing seems too good to be true…

Before jump­ing on the sup­ple­ment train, make sure to learn the truth about dietary supplements.

Types of Dietary Supplements

Dietary sup­ple­ments are prod­ucts that you add to your diet in addi­tion to con­ven­tion­al food. They’re con­sumed via inges­tion and come in many shapes and sizes, like pills, pow­ders, liq­uids, bars, skin patch­es, and gummies.

Also read: The Low-Down on Low Magnesium

Risks of Dietary Supplements

Unless you have trou­ble get­ting nutri­ents nat­u­ral­ly or your provider pre­scribes sup­ple­ments, you might be wast­ing your mon­ey. There isn’t enough research to show that sup­ple­ments are effec­tive. The stud­ies that have been con­duct­ed gen­er­al­ly show that extra vit­a­mins and min­er­als do not pro­tect against dis­ease or improve over­all health in peo­ple who are oth­er­wise healthy.

In addi­tion to not always work­ing, it can be risky to take dietary supplements.

A Word from Our Doctor

“As an avid researcher, I enjoy div­ing deep in the details of new cut­ting edge research in peer reviewed med­ical jour­nals. I’ll do the heavy lift­ing for you, break it down into con­sum­able pieces, and guide you through a plan to reach your goals in a straight­for­ward, evi­dence based approach.”

–  Ale­jan­dro Gon­za­lez, MD, Fam­i­ly Med­i­cine Physi­cian at Duly Health and Care

Need guid­ance on the best sup­ple­ments for you? Duly Health and Care part­ners with Fullscript to take the guess­work out of sup­ple­ments, giv­ing patients access to safe, high-qual­i­ty options. Sched­ule an appoint­ment with one of our providers to learn more.

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You Can Get Too Much of a Good Thing

Your body only needs a cer­tain amount of each nutri­ent per day. When you go over that amount, there are sev­er­al risks. For instance, here’s what could hap­pen if you get too much of cer­tain nutrients:

• Vit­a­min A: Nau­sea and vom­it­ing, drowsi­ness, irri­tabil­i­ty, and beta-carotene sup­ple­ments (a pre­cur­sor of vit­a­min A) have shown an increased risk of lung can­cer in cur­rent and for­mer smok­ers, accord­ing to large tri­als (CARET, ATBC).
• Cal­ci­um: Irreg­u­lar heart­beat, con­fu­sion, kid­ney dam­age, and increased risk of kid­ney stones or, rarely, milk-alka­li syndrome.
• Niacin (Vit­a­min B3): long-term high dos­ing can lead to liv­er injury, ocu­lar effects, and glu­cose issues (NIH).
• Biotin (Vit­a­min B7): often used for nail and hair growth, can inter­fere with lab tests, includ­ing tro­ponin, lead­ing to false results (FDA). Be sure to tell your clin­i­cian before labs if you are con­sum­ing this.

Sup­ple­ments Can Inter­act With Oth­er Medications

Be care­ful not to fall into the trap of think­ing that, just because sup­ple­ments are nat­ur­al, they are safe – espe­cial­ly if you take dai­ly med­ica­tion or have cer­tain med­ical conditions.

Just like med­ica­tions, sup­ple­ments can cause bad side effects if they are mixed with med­ica­tions you are cur­rent­ly tak­ing or oth­er sup­ple­ments. For exam­ple, St. John’s wort can reduce the effec­tive­ness of oth­er drugs, includ­ing many heart med­ica­tions (blood thin­ners, statins, and heart rhythm med­ica­tions). It can also affect med­ica­tions that pre­vent organ trans­plant rejec­tion, anti-HIV med­ica­tions, and birth con­trol pills by poten­tial­ly caus­ing break­through bleed­ing and increas­ing the like­li­hood of a woman get­ting pregnant. 

Vit­a­min C and oth­er antiox­i­dant sup­ple­ments have shown they may wors­en out­comes in chemother­a­py; it is rec­om­mend­ed to dis­cuss use with your oncol­o­gist if con­sum­ing. Tak­ing vit­a­min E sup­ple­ments when you’re on the blood thin­ner war­farin can result in an increased risk of bleed­ing, and some analy­ses have linked high-dose Vit­a­min E with increased risk of hem­or­rhag­ic stroke.

They Aren’t Reg­u­lat­ed the Same Way as Medications

Dietary sup­ple­ments are reg­u­lat­ed by the US Food and Drug Admin­is­tra­tion (FDA), but not nec­es­sar­i­ly in the way you think. 

Sup­ple­ments are reg­u­lat­ed by the FDA under the Dietary Sup­ple­ment Health and Edu­ca­tion Act (DSHEA). They’re not approved for safe­ty or effi­ca­cy before mar­ket­ing; man­u­fac­tur­ers are respon­si­ble for safe­ty and label­ing, must fol­low cGMPs, and cer­tain new dietary ingre­di­ents require a 75-day pre­mar­ket noti­fi­ca­tion. The FDA takes post-mar­ket action when need­ed if a sup­ple­ment has been report­ed to cause harm after its been broad­ly avail­able for consumption.

In oth­er words the FDA has light reg­u­la­tion pro­to­cols for sup­ple­ments that are not as strin­gent as med­ica­tion reg­u­la­tions. Ulti­mate­ly, they are respon­si­ble for mon­i­tor­ing sup­ple­ments after they’ve hit the mar­ket to ensure they aren’t caus­ing harm, inspect­ing man­u­fac­tur­ing facil­i­ties, and, if need­ed, remov­ing them from the marketplace.

Also read: Good­bye Dr. Google and Self-Diag­no­sis: 5 Pit­falls of Act­ing Like Your Own Doctor

Ben­e­fits of Dietary Supplements 

Despite the risks, sup­ple­ments aren’t nec­es­sar­i­ly off the table. There are times when sup­ple­ments can be beneficial.

Sup­ple­ments can help you meet your dai­ly require­ments for essen­tial nutri­ents if you have trou­ble meet­ing those require­ments nat­u­ral­ly. In these cas­es, your provider may rec­om­mend over-the-counter sup­ple­ments or pre­scribe stronger ones. For exam­ple, peo­ple fol­low­ing a veg­an diet often don’t eat enough foods with vit­a­min B‑12. 

As peo­ple get old­er, their skin has a hard­er time pro­duc­ing vit­a­min D. Sit­u­a­tions like these can lead to defi­cien­cies, which can cause prob­lems rang­ing from fatigue to bone pain to irreg­u­lar heart­beat. By tak­ing sup­ple­ments, you might be able to avoid defi­cien­cies. When they’re tak­en cor­rect­ly and safe­ly, sup­ple­ments may help with:

• Build­ing strong bones and reduc­ing bone loss, like Vit­a­min D along with Cal­ci­um found in foods.
• Hav­ing reg­u­lar bow­el move­ments if suf­fer­ing from chron­ic con­sti­pa­tion with psyl­li­um as evi­dence by RTCs and meta-analy­sis (Pubmed).
• Slow­ing down vision loss in peo­ple with inter­me­di­ate age-relat­ed mac­u­lar degen­er­a­tion (AMD), specif­i­cal­ly AREDS2 for­mu­la (NIH). 

Also read: What Does Vit­a­min D Do? 5 Ques­tions Answered

Sup­ple­ments and Pregnancy

Dur­ing preg­nan­cy, it’s crit­i­cal to meet nutri­ent require­ments. Nutri­ents help with a healthy preg­nan­cy and pro­tect your devel­op­ing baby’s health. While diet is the best way to get these nutri­ents, preg­nant women often fall short on nutri­ents. That’s where pre­na­tal vit­a­mins come in.

It’s rec­om­mend­ed that women who are or may become preg­nant take 400 mcg of folic acid dai­ly, as well as 600 mcg of folic acid dur­ing preg­nan­cy (CDC). Folic acid is the most impor­tant vit­a­min to take dur­ing preg­nan­cy, as it reduces the risk of cer­tain birth defects and sup­ports a fetus’s growth and development.

Anoth­er very impor­tant vit­a­min dur­ing preg­nan­cy is iron, 27 mg/​day. Iron helps your red blood cells sup­ply oxy­gen to the fetus. It can also decrease the risk of ane­mia (when your blood doesn’t have enough healthy red blood cells).

Depend­ing on your needs dur­ing preg­nan­cy, your provider may also rec­om­mend tak­ing addi­tion­al pre­na­tal vit­a­mins, such as cal­ci­um, vit­a­min D, or iodine.

Get­ting Those Nutri­ents In

Sup­ple­ments should nev­er replace a healthy diet. Whether you’re tak­ing sup­ple­ments or not, look for nat­ur­al ways to get the nutri­ents you need through the foods you con­sume. Eat foods that are packed with essen­tial nutri­ents, includ­ing fruits and veg­eta­bles, whole grains, and nuts and legumes. 

Stay phys­i­cal­ly active, since exer­cise helps nutri­ents get where they need to go in your body. If you’re tak­ing or are inter­est­ed in tak­ing sup­ple­ments, make sure you fol­low these steps for tak­ing them safe­ly and max­i­miz­ing their benefit.

• Only take sup­ple­ments after talk­ing to your provider or with a provider’s prescription.
• Fol­low dos­ing direc­tions care­ful­ly and don’t take more than recommended. 
• Nev­er sub­sti­tute a sup­ple­ment for a pre­scribed medication.
• Let all your providers (includ­ing your pri­ma­ry care provider, spe­cial­ists, and providers at imme­di­ate care cen­ters or emer­gency rooms) know about any sup­ple­ments you’re tak­ing before labs or procedures.

The most impor­tant thing to do is to work hand-in-hand with your provider. They can help you find ways to get the nutri­ents you need, whether it’s adjust­ing your lifestyle, tak­ing sup­ple­ments, or a com­bi­na­tion of both.

With Fullscript, Duly Health and Care providers can rec­om­mend safe, evi­dence-based sup­ple­ments tai­lored to your needs. Sched­ule an appoint­ment with one of our providers to dis­cuss the best options tai­lored to your needs.

Need to be seen today? We offer same-day pri­ma­ry care appoint­ments 7 days a week at our loca­tions through­out Chicagoland.

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This arti­cle was med­ical­ly reviewed by Ale­jan­dro Gon­za­lez, MD.