The supplement aisle is booming, with billions spent annually on everything from basic multivitamins to specialized herbs. However, research shows that simply “popping a pill” without an informed strategy can render your supplements ineffective, lead to poor absorption, or even cause dangerous interactions. To ensure you’re not wasting money or risking your health, the following are the most common supplement mistakes you should stop making, backed by science.
Common Supplement Mistakes: The Truth About Supplements and Health
The first and most important thing to mention here is that supplements are just that – supplemental. You can’t out-supplement poor lifestyle habits. Before turning to supplements, it is crucial to establish a strong foundation of nutrition, sleep, exercise, hydration, and stress management. Supplements are powerful tools, but they are designed to supplement an already healthy lifestyle, not replace it. Relying on pills to compensate for poor diet or chronic sleep deprivation is like putting a bandaid on a bullet hole and expecting it to solve the problem. In reality, supplements will fail to address the underlying problem, providing little, if any, relief at all. From a scientific standpoint, for individuals who are not clinically deficient in a specific nutrient, very few supplements consistently show a noticeable improvement in overall well-being or performance. Research indicates that the most significant benefits of supplementation are seen when correcting a diagnosed deficiency (eg. iron for anemia, vitamin D for low levels), validating the principle that optimal health starts with meeting fundamental physiological needs first.
“It really is the case that more is not necessarily better,” says Harvard epidemiology professor JoAnn Manson to the BBC. “But multivitamins are very safe, so I think if anyone has concerns about whether they’re getting an adequately healthy balanced diet, taking a multivitamin could be a form of insurance to make sure they’re getting these essential vitamins and minerals.”
Now that we’ve covered that, let’s get into the mistakes that people make while taking their supplements. These mistakes could be simply rendering your supplements useless, but some can actually be dangerous to your health. It is important that you understand them and always consult a doctor or registered dietitian before starting a new supplement.
Mistake 1: Causing an Absorption War and Ignoring Drug Interactions
One of the most critical errors in supplementing is taking competing nutrients together or combining them with prescription medications that interfere with their efficacy or safety. It is important to understand these interactions for your health and safety, as well as your wallet – you are wasting money if you are taking something and not absorbing it. As always, check with your doctor before taking a supplement, especially if you are already taking any prescription medications.
The Mineral Competition
When multiple minerals are taken in large doses simultaneously, they can compete for absorption in the gut. They are effectively neutralizing each other’s benefits. The following minerals compete for absorption when taken together:
- Calcium and Iron: Calcium is known to interfere with iron absorption. To maximize the uptake of both essential minerals, these supplements should be spaced out by at least a couple of hours. Ideally, you will avoid taking an iron supplement alongside calcium-rich foods, as well.
- Calcium, Magnesium, and Zinc: These three minerals also vie for the same absorption pathways. Taking them all at once can reduce the benefit of each. A common recommendation is to take them at separate times of the day, or to choose a combination product with carefully formulated ratios.
- Multivitamins and Individual Minerals: If your multivitamin already contains a range of minerals, adding a high-dose individual mineral supplement, such as extra magnesium or zinc, on top can create a competitive environment and should generally be avoided.
Dangerous Drug-Nutrient Combinations
As already mentioned, in some instances, certain supplements may have negative interactions with medications. These interactions can be quite severe and highly dangerous to your health. You must consult with your doctor before taking new supplements if you are on prescription medications for your own safety.
- St. John’s Wort and Ginseng: Combining these two can lead to overstimulation of the central nervous system, potentially causing agitation, a rapid heart rate, or a life-threatening condition called serotonin syndrome. Furthermore, St. John’s Worst can dangerously reduce the efficacy of widely prescribed medications, including oral contraceptives, statins, and antidepressants.
- Probiotics and Antibiotics: Antibiotics are designed to kill bacteria, which means they can also destroy the beneficial bacteria in your probiotic. To preserve the probiotic’s effectiveness, take it at least two hours apart from your antibiotic dose.
- Vitamin E and Vitamin K: Vitamin E has a blood-thinning effect, which can increase the risk of bleeding. This effect counteracts the blood-clotting role of vitamin K. Taking high doses of both together can be unsafe. Also, taking vitamin E when you are already taking blood thinners can be very dangerous. On the other hand, vitamin K combines well with vitamin D
Mistake 2: Poor Timing and Incorrect Dosing
Just as important as which supplements you choose to take are the time of day you take them and the specific dose. This can either positively or negatively affect absorption and uptake by the body.
Timing for Optimal Efficacy
Nutrients interact differently with an empty stomach versus a full one. Some you should take with food, others no, and others will depend on your personal needs. In general, you can follow this guideline:
- Take minerals with food: Mineral supplements like calcium, magnesium, and zinc can be easier on the stomach and better absorbed when taken with a meal.
- Respect the empty stomach rule: This goes especially for individuals on thyroid medications. Certain medications, most notably Levothyroxine for hypothyroidism, must be taken on an empty stomach because minerals like calcium, magnesium, and iron can significantly interfere with its absorption. A common clinical practice is to take the thyroid medication first, and then wait a few hours before taking any mineral supplements.
- Time supplements to your lifestyle: Strategic timing can maximize a supplement’s functional benefit. For example, many people take magnesium glycinate in the evening to complement their wind-down routine and aid in relaxation and sleep. Similarly, if a prenatal vitamin causes morning nausea, taking it in the evening instead may help.
- Time supplements for the benefit you seek: For example, if you are taking Zinc, Copper, Selenium, Vitamin D, Vitamin B6, Vitamin B12 and Folate to boost your immune system, it is better to take this before bed. This is because some immune cells, particularly T-lymphocytes, have shown to experience peak production during the night.
The Problem with Senseless Dosing
The dose you choose to take of a supplement can vastly impact how that supplement makes you feel. It can also become dangerous if dosed incorrectly. Taking a dosage that makes no sense is a common pitfall that many people tackle. Whether it’s comically low or frighteningly high, an incorrect dose wastes money and can harm your health. Always confirm the correct therapeutic dosage with a healthcare provider. Furthermore, be aware that even compounds your body naturally produces, like melatonin, have upper limits when taken in supplement form.
Mistake 3: Taking the Wrong Form or Not Confirming Your Need
A supplement only works if you actually need it and if your body can absorb the specific form you’re taking. Often, people spend a lot of money on supplements only to create really expensive urine. This is because their body is getting rid of the extra that it doesn’t need. Most of the time, people get the amount their body needs through diet alone.
The Principle of “Test, Don’t Guess”
Many people start a supplement based on a general feeling (e.g. low energy) without confirming a deficiency. This not only can waste your money, but it can put your health at risk. For example, taking a vitamin B12 supplement for energy when your levels are already normal means any excess B12 will simply be removed from your body via urine. Nutrients like vitamin D are fat-soluble, and are not easily excreted. Taking extremely high doses without a confirmed deficiency can lead to dangerously high blood levels, potentially causing symptoms like constant vomiting, diarrhea, and extreme thirst.
The Form Matters
Different chemical forms of the same nutrient can have vastly different effects on your body and its absorption. Magnesium glycinate is often recommended for nighttime relaxation, while magnesium citrate and magnesium oxide are commonly used as laxatives. Taking the wrong form can produce the opposite of your desired result. Iron supplements, on the other hand, are known for causing gastrointestinal distress. However, forms like ferrous bisglycinate have been shown in studies to be less likely to cause nausea and constipation than older forms like ferrous sulfate.
Mistake 4: Overcomplicating and Doubling Up
A “kitchen sink” approach to supplementing can be counterproductive and costly. The following are the most common errors people make when it comes to overcomplicating their routine:
- Unnecessary Doubling Up: It’s easy to knowingly consume the same nutrients from multiple sources. For instance, taking a hair, skin, and nails supplement, a B-complex, and a prenatal all at once means you’re consuming the same B vitamins from three separate products. This can result in excessive and/or unnecessary intake.
- Excessive Ingredient Lists: Be skeptical of ultra-comprehensive formulations or proprietary blends that pack hundreds of ingredients into a single pill or scoop. It’s challenging to fit many high-quality, active ingredients into one formulation, and proprietary blends often leave consumers in the dark about the exact dosages of what they are consuming.
The Crucial Caveat
“Supplements are products marketed to consumers to supplement their diet,” says Oklahoma State University Extension nutrition specialist Janice Hermann. “They can help a person maintain or improve overall health. While supplements can be beneficial, there can be some risks in consuming them. And, they shouldn’t replace the foods in a healthy diet.”
While supplements can play a valuable role in a healthy lifestyle, they are not a substitute for medical guidance. The top mistake you can make is operating without professional oversight. Always talk to your doctor or a registered dietitian before starting any new supplement, especially if you have a pre-existing health condition or take prescription medications. Additionally, check with the product manufacturer or a healthcare practitioner to ensure you are taking any supplements in a way that is both safe and effective. Being informed about drug-nutrient interactions is the key to maximizing the benefits of your supplements while minimizing potential risks.
Disclaimer: This information is not intended to be a substitute for professional medical advice, diagnosis or treatment and is for information only. Always seek the advice of your physician or another qualified health provider with any questions about your medical condition and/or current medication. Do not disregard professional medical advice or delay seeking advice or treatment because of something you have read here.
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