Myths and truths about dietary supplements

Supplements have carried a health halo for years, but are they really all they’re cracked up to be? From drug/nutrient interactions to overdosing and regulations, here’s what you need to know regarding the myths and truths about dietary supplements.

Whether you’re trying to boost immunity, regulate blood sugar, or improve performance, chances are you’ve turned to supplements to achieve results and enhance overall health. And you’re not alone; recent statistics have found that 79% of Americans say that taking supplements is important to their health, 67% of supplement users plan to continue using supplements, and 49% are willing to spend more on supplements [



With so many people hopping on the supplement train, it’s easy to see why there’s a health halo surrounding this topic. Since supplements are often touted as the end-all-be-all to curing your ailments and achieving athletic prowess, it stands to reason that by taking them, you’ll evade the cold, run a sub-6 minute mile, and have glowing skin while doing so.

However, not all supplements are created equal--while some are supported by science, others offer no clear benefit and can even be harmful to your health. So, how can you distinguish the good from the bad to determine what (and if) supplements are right for you?

To set the record straight, we’re diving into the science to bust nutrition myths on dietary supplements. From drug/nutrient interactions to overdosing and regulations, here are the myths and truths about dietary supplements.

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Myth: Supplements are a waste of money.

Truth: Taking the right supplements is an investment into your health.

Navigating supplements is messy, complicated, and fraught with misinformation. They can also be expensive, so it may seem like you’re throwing money down the drain if you don’t see any results. However, supplements aren’t a waste of money if you invest in the right ones that make up for any shortfalls in your diet and fit your nutritional needs.

Let’s take

vitamin D

as an example. Vitamin D plays a critical role in bone health, immunity, and blood sugar (among other things), so if you’re deficient, you may be at a higher risk of bone fractures, COVID-19, and various other conditions. As such, spending money on a high quality vitamin D supplement at the right dose can have a meaningful impact on your health.

Supplements are also not a waste of money if you follow a vegetarian or vegan diet. These plant-based eating styles tend to fall short in certain vitamins and minerals (such as vitamin B12, omega-3 fatty acids, and iron), so by taking targeted supplements serves as an important safety net, and can help minimize your risk of nutrient deficiencies with far-reaching health consequences. For example, vitamin B12 deficiency, can lead to nerve damage and megaloblastic anemia which is characterized by shortness of breath, weakness, tingling, swollen tongue, and diarrhea.

hand with gummy in front of a neutral wall

Invest in your health with Elo.

Not all supplements are created equal, but when you take the right supplements, you’re making an investment in your health that can resonate for years to come. At Elo, we help improve your health and performance by providing supplements made just for you. Discover your custom gummy formula today!

Myth: Taking a multivitamin can make up for a poor diet and prevent disease.

Truth: Dietary supplements should not be used as a substitute for eating a healthful diet.

While taking a multivitamin can provide missing vitamins and minerals, it won’t mitigate the other health risks that come with a poor diet. 

A poor diet usually consists of refined sugars, processed foods, and trans-fats, and has been linked to a risk of chronic disease, obesity, inflammation, and cancer [




]. Conversely, eating a healthful diet rich in fruits, vegetables, whole grains, healthy fats, and lean protein has been shown to be one of the best strategies to prevent disease, reduce the risk of cancer, and extend your lifespan [





As such, multivitamins and dietary supplements should be consumed in tandem with a nutritious diet, not in place of it.

Elo smart gummies in hand

Myth: Supplements are tightly regulated. 

Truth: Supplements don’t need to be FDA approved before they hit the market unless they contain an ingredient that hasn’t been sold before.

Unlike food, supplement regulation is largely in the hands of manufacturers and FDA approval for supplements is only required when the product contains a new ingredient.

According to the FDA, every dietary supplement needs to be labeled with the term "dietary supplement" or with a term that substitutes a description of the product's dietary ingredient(s) for the word "dietary" [


]. However, federal law states that supplements don’t need to be FDA approved before they are marketed, which means that the manufacturer or seller can add inaccurate or untruthful claims to supplements.

At Elo, we employ a number of fail-safe measures to ensure that our products are safe and effective. All of our products undergo rigorous third-party testing to ensure purity, dosage and freshness. Learn more about Elo's third-party testing process in

this article


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Myth: Supplements are never necessary.

Truth: Supplements are necessary if you are deficient in certain vitamins and minerals.

While you can get many nutrients from a healthful, well-balanced diet, you may not get all of them on a regular basis, especially if you eat a typical Western diet. 

Studies have found that only 28% of adults eat their recommended five servings of fruit and vegetables each day, leaving many people with nutrient gaps [




]. Additionally, research shows that Americans consume less than the recommended daily intake for vitamins A, C, E, K, as well as magnesium, potassium, choline, and vitamin K [



Here are a few other shortfall nutrients that have been linked to an increased risk of chronic disease, inflammation, bone fractures, and illnesses. 

  • Vitamin D. Studies show that 42% of Americans are deficient in vitamin D, with that number increasing to 74% in older adults and 82% in people with dark skin [


    ]. 90% of Elo members start with low

    vitamin D


  • Omega-3 fatty acids. New research has found that over 68% of adults and 95% of children in the United States do not consume enough omega-3s [



  • Iron. Iron deficiency affects more than 25% of people worldwide and is the most common nutrient deficiency globally [



  • Iodine. Iodine deficiency is one of the most common nutrient deficiencies, affecting nearly a third of the world’s population [



  • Vitamin B12. Studies show that vegetarians and vegans are more at risk for deficiency in vitamin B12 [



  • Calcium. Fewer than 15% of teenage girls, fewer than 10% of women over 50, and fewer than 22% of teenage boys and men over 50 in the United States meet the recommended calcium intake [



If you’re deficient in these nutrients, supplementation may be necessary to meet your nutritional needs and help bridge any gaps. 

Additionally, certain supplements may be necessary to maintain health, as research has shown that they may have significant benefits for specific groups and indications. For instance, alpha lipoic acid has been shown to be beneficial for cholesterol reduction, and vitamin C may reduce the duration of cold symptoms [




]. Moreover, folic acid decreases the risk of neural tube defects, whereas omega-3 fatty acids might help reduce the risk of cardiovascular disease [





woman with black hair holding Elo smart gummies

Myth: All supplements play well together. 

Truth: Not all supplements work synergistically.

While some vitamins and minerals work synergistically, there are others that can cause a deficiency when taken simultaneously.

Here are some nutrients that play well together:

  • Magnesium and vitamin D. These two nutrients benefit bone health, as magnesium helps activate vitamin D, which helps regulate calcium and phosphate to influence the growth and maintenance of bones [



  • Vitamin C and iron. Studies have found that you can enhance iron absorption by pairing it with foods high in vitamin C [



  • Calcium and vitamin D. Both of these nutrients play a role in skeletal health. Calcium helps build and maintain bones, whereas vitamin D helps your body effectively absorb calcium. While they offer benefits on their own, they are more effective when taken together [



  • Omega-3 and vitamin E. Studies have found that omega-3 and vitamin E work together to decrease insulin resistance and improve cholesterol levels in people with coronary artery disease [



  • Magnesium and zinc. When taken together, magnesium and zinc may boost your immune system, reduce CRP (a marker of inflammation), regulate blood sugar levels, and improve sleep quality [







Conversely, here are some nutrients that work against each other, and should be taken at separate times under the supervision of a healthcare professional:

  • Calcium and iron. Studies have shown that 1,000 mg of calcium can inhibit nonheme iron absorption by 49.6% [



  • Zinc and copper. Zinc reduces the amount of copper your body absorbs and high doses can cause a copper deficiency [



Supplements can be confusing, so work with your healthcare provider to find the right fit for you. 

Tommy Caldwell holding gummies next to his eyes

Myth: Supplements always do what they say they do.

Truth: Supplements can be misleading and make unsubstantiated claims.

While it’s illegal for manufacturers to claim that supplements treat, diagnose, prevent or cure diseases, they can mislead consumers with marketing tactics and clever wording. These unsubstantiated claims often overpromise and under-deliver, as there is little research to back them up.

This is where Elo is different. Our supplement recommendation engine is built on a proprietary analysis of over 3,500 peer-reviewed human clinical studies to ensure that each unique supplement formulation is underpinned by a firm foundation of science. Nutrient dosage and timing is determined by the latest clinical evidence as well as your individual biomarker results, health history and wearable data. 

Myth: You can’t overdose on supplements.

Truth: You can experience vitamin toxicity if you’re not careful.

Although supplements offer many health benefits, you can have too much of a good thing, as overdosing on certain vitamins can lead to negative side effects and in some instances, be dangerous to health. Some examples include:

  • Vitamin A. Excess amounts over 10,000 IU/day may lead to skin issues (like reddening, irritation, and patchy peeling), as well as vision changes, nausea, dizziness, migraines, and bone pain [



  • Vitamin C. Large doses can affect digestion, causing diarrhea, cramps, and nausea [



  • Vitamin E. Daily doses of 400 IU or more may increase your risk of prostate cancer [



  • Iron. Research shows that more than excess iron can lead to unpleasant symptoms such as GI discomfort, constipation, nausea, vomiting, and fainting [



  • Iodine. Symptoms of iodine toxicity include nausea, vomiting, and diarrhea [



In most cases, side effects will resolve themselves when you stop taking excess amounts of the respective supplement. However, you should talk with your healthcare provider before starting a supplement routine to make sure it’s right for you.

Tommy Caldwell holding gummies

Myth: Supplements always contain what their labels say.

Truth: Supplements are not tested by the FDA before they go to market unless they contain a new ingredient.

Supplements are not tested by the FDA and as such, the ingredients on the label may not be an accurate reflection of what’s in the bottle. 

One study compared vitamin D supplements from different manufacturers and found that the amount of vitamin D provided  was between 52% and 135% of the dosage listed on the label [


]. This inaccuracy can prove dangerous, as the dosage matters when it comes to drug/nutrient interactions and potential toxicity levels. Moreover, some supplements have been found to contain contaminants (such as metals, toxins, pesticides, dioxins and PCBs) and banned substances for athletes [



Myth: Supplements never interact with drugs.

Truth: Supplements may interact with drugs, altering their effectiveness.

While certain supplements can enhance a medication’s effectiveness, others can negatively interact with drugs and alter their absorption, metabolism, and potency. 

Combining supplements and medications can be fraught with risks and you should speak with your healthcare professional before starting a new supplement routine or adding a new one into your regimen.

Here are some examples of drug/nutrient interactions:

  • Vitamin K. This vitamin is involved in blood clotting and can interfere with warfarin, a prescription blood thinner [



  • Ashwagandha. Taking ashwagandha and immunosuppressants simultaneously may reduce the effects of the medication. Ashwagandha can also lower blood pressure, so taking both ashwagandha and antihypertensive medications may cause blood pressure to drop too low [



  • Cinnamon. Cinnamon may interact with diabetic medications and could put you at risk of low blood sugar (hypoglycemia) [



  • Aloe vera. Aloe vera has been shown to interact with certain drugs –especially insulin, diuretics, laxatives, and NSAIDs–and may lower the absorption and effectiveness of these medications [



  • Berberine. Berberine can interact with certain medications like Cyclosporine, Dextromethorphan, Losartan, and any others that are metabolized by the liver [



  • Magnesium. When combined with other medications, magnesium may increase the risk of hypoglycemia [



  • Alpha-lipoic acid. ALA can interact with glucose-lowering medicines [




With so many people hopping on the supplement train, it’s easy to see why there’s a health halo surrounding this topic. However, not all supplements are created equal--while some are supported by science, others offer no clear benefit and can even be harmful to your health. As such, you should talk with your healthcare provider before starting a supplement routine or adding certain ones into your regimen.

Disclaimer: The text, images, videos, and other media on this page are provided for informational purposes only and are not intended to treat, diagnose or replace personalized medical care. 

Key takeaways

  • Supplements aren’t a waste of money if you invest in the right ones that make up for any shortfalls in your diet and fit your nutritional needs.

  • Dietary supplements should not be used as a substitute for eating a healthful diet.

  • While some vitamins and minerals work synergistically, there are others that can cause a deficiency when taken simultaneously.

  • Combining supplements and medications is fraught with risks. Speak with your healthcare professional before starting a new supplement routine or adding certain ones into your regimen.

  • Elo’s rigorous third-party testing process is an anomaly in the industry. Supplement regulations are often murky; however, Elo has established a system to ensure that our products are the best in class.


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