5 Supplements You Shouldn't Be Taking, According to a Dietitian

You might be better off saving your money than buying these.

Welcome to Thrifty. A weekly column where nutrition editor and registered dietitian Jessica Ball keeps it real on how to grocery shop on a budget, make healthy meals for one or two, and make Earth-friendly choices without overhauling your entire life.

Supplements are a billion-dollar industry—$152 billion in 2021, to be exact. The range of different products on the market seems endless, and they all claim to help improve your health in one way or another. Don't get me wrong; there are some supplements that can actually be worthwhile, especially for nutrients you have a hard time getting in your diet (like iron or vitamin D if you follow a vegetarian or vegan diet). But several are not worth the hype—or the money. Here I'll break down five supplements I'd recommend skipping as a registered dietitian.

a photo of a man taking a supplement with a glass of water
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5 Supplements You Shouldn't Be Taking, According to a Dietitian

1. Weight-Loss Supplements

Let's start by clarifying that improving your health may not always result in weight loss, and not all weight loss is healthy. And weight-loss supplements are an example of this. Weight-loss goals are typically hard to achieve, and the resulting frustration has opened the door for several "quick fix" products, powders and pills that promise results fast (usually via murky mechanisms). But the fact of the matter is that they aren't usually effective. A 2021 review published in the journal Obesity looked at 315 clinical trials and found that weight-loss supplements did not produce much or any weight loss among participants. Plus, even if a supplement worked for you, the weight loss would only be sustained as long as you took the supplement.

In addition, these supplements are not regulated by the Food & Drug Administration, so it can be hard to know what exactly is in them … or if they're even safe. They also typically come at a high price point, so you could spend a bunch of money, potentially ingest something harmful and not even see results from it—hard pass. Instead, focus on making small changes to your lifestyle and eating pattern and adding movement where you can. This is a much better bet if you want to lose weight, and it will probably make you feel better in the process.

2. Supplements without Third-Party Certification

There are over 80,000 supplements available on the market. So, what's a quick way to cut through the noise? Look for a third-party certification. Since the FDA does not review any products before they go to market, there is typically little accountability for producers. One way that producers can display that the ingredients in their products are accurate and safe is by obtaining a third-party certification, such as NSF, USP, Informed Sport or BSCG (check out this scorecard to see what logos to expect). If a supplement doesn't have any third-party certification, even if it's a single ingredient or a vitamin, I'd suggest skipping it and opting for one that does.

3. Supplements That Interfere with Your Medications

If you are taking any medication, be sure to consult with your health care team before trying a new supplement. In my undergraduate education in dietetics, I vividly remember the heavy book on food and drug interactions that I lugged around in my backpack for class. So many nutrients impact different medications, and it's not something that's displayed when you purchase a supplement. For example, vitamin K can impact blood-thinning medication like Warfarin, and people on Warfarin typically need to monitor their vitamin K intake closely. In this case, a vitamin K supplement would not be safe for someone on this medication. That's why it's important to talk to a professional before starting something new, even if it's just a single-ingredient vitamin or mineral.

4. Caffeine Supplements

Caffeine is arguably the most popular drug in the world, and in moderation, it can even boast some health benefits. Drinks like coffee and tea are packed with antioxidants and anti-inflammatory compounds, which can give you an energy and nutrition boost, and it can be easier to tell when you're drinking too much. But high-dose caffeine supplements are easy to take and usually contain two to three times more caffeine per pill than an 8-ounce cup of coffee, which is probably more than you would usually consume in one sitting. Besides shakiness, anxiety and jitters in the short term, regularly overdoing it on caffeine can mess with your mental health, make certain medical conditions like heart disease and diabetes worse and can negatively impact your sleep. If you're feeling tired on the road or in a pinch, opt for another form of caffeine and skip the jitter-inducing supplements.

5. High-Dose Supplements

There are numerous vitamins and minerals that our body needs to thrive. But too much of a good thing can sometimes be not so good for us, and nutrients are no exception. Many vitamins and minerals have what's called a "tolerable upper limit" (UL). This is the maximum daily intake that is unlikely to cause adverse effects. Exceeding these limits can create too high of a concentration of the nutrient in our bodies and can lead to adverse health effects, particularly for fat-soluble vitamins (like A, D, E and K) or heavy metals (like iron, copper and zinc). Since supplements aren't vetted before they go to market, there is no standardized way to check that the dose they are recommending is below the UL. Not only are super-high-dose supplements unnecessary, but they could also potentially be dangerous.

This is why it's important to do a bit of research and have a specific idea of what you want before shopping for a supplement. The Daily Recommended Intakes are a good place to start to get an idea of how much you need, and also consider if you regularly consume food sources of the nutrient (which is usually a better way to meet your needs). Supplements are meant to do just that: supplement your food intake to help you meet your needs. So skip the high-dose supplements and choose one that can help you fill in the gaps without overdoing it.

The Bottom Line

Many supplements have merit and might improve your health by helping you meet your nutritional needs. But there are also several supplements that are unsafe, ineffective and, frankly, not worth the money. If you take supplements, these five might be best to skip. The money you save could go toward nutritious whole foods that are great, safe and tasty vehicles for nutrition.

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