As of 2019, more than three-quarters of U.S. adults now count supplements as part of their regular routine. But how many supplement users actually know what’s in their capsule, chew, or powder?

“Just like with food, it’s important for people to know what they’re ingesting when taking a supplement,” says Jim White, R.D., dietitian and owner of Jim White Fitness and Nutrition Studios. After all, supplement ingredients vary—and their labels aren’t always easy to understand.

Nope, you’re definitely not the only one confused by the back of that supplement bottle. To make your routine as beneficial as possible, here’s everything you need to know to decode a supplement label like a pro.

Start With The Basics

The following five statements are required on every supplement label, White says. To better understand a product, start here.

1. Statement Of Identity

“This is the name of the dietary supplement,” White says. Make sure the name fits what you’re looking for (like “vitamin B6”). If you’re not sure, check the nutrition label and ingredients list. (More on them in a minute).

2. Net Quantity Of Contents

Found on the front of the label, this reflects the amount of the dietary supplement in the container (like 60 capsules or a net weight of 16 fluid ounces).

After looking at this, check the supplement’s serving size. (Just because a bottle contains 60 capsules doesn’t mean it contains 60 servings.) Knowing the number of servings in a product may help you decide between two options, if price is an issue.

3. Nutrition Label

Also known as the ‘Supplement Facts’ panel, the nutrition label on the back of a product lists the names and amounts of each ingredient in a supplement, along with the recommended serving size for each.

Read More: Ask These 6 Questions Before Buying A Multivitamin

Be aware that it’s possible for a supplement to contain amounts of nutrients that exceed the tolerable upper intake level (UL), or the maximum recommended daily amount. And this piece of information won’t be listed on the label, White says.

Too-high intakes of certain vitamins and minerals may cause negative effects. Too much vitamin C, for example, may cause diarrhea, nausea, abdominal cramps and other gastrointestinal issues, according to the National Institutes of Health (NIH).

Check the nutrient amounts in your supplement against the NIH’s UL list to make sure you’re not getting too much of any single nutrient.

4. Ingredient List

As you might guess, the ingredient list tells you what ingredients (nutrients, flavorings, sweeteners, etc.) are in a product. If there’s no ingredients list, all of a product’s ingredients are already listed on the supplement facts panel.

5. Manufacturer Name And Location

Typically found on the back, supplement labels also include where the product was made and who made it, White says. If you have any questions or concerns about a product, look into the manufacturer’s credibility. (The FDA doesn’t require dietary supplement manufacturers to prove the safety and efficacy of their products before they hit the market.)

Consider Claims

Many product labels sport claims or statements about what the product does or does not contain, and is or is not intended to do. (A few examples: ‘good source of fiber’ or ‘no sugar added.’)

“Be aware, though, that the FDA prohibits supplement companies from making claims that their products treat, diagnose, prevent, or cure diseases,” White says. If you see any claims like this on a supplement label, put it back on the shelf.

Seek Out Seals And Certifications

You know those shiny seals you see on the fronts of many products? They often reflect extra testing or certifications a manufacturer has sought out to confirm the quality of their products.

A few indicators of quality to look out for: third-party testing seals from organizations like NSF International, ConsumerLab, and United States Pharmacopeia (USP). These seals confirm that a supplement contains exactly what it lists on the label, so you know you’re consuming a high-quality product.

If you’re interested in supplements that are organic or made with non-genetically modified ingredients, specifically, look for seals that read ‘USDA Organic’ or ‘Non-GMO Project.’

To obtain a ‘USDA Organic’ seal, at least 95 percent of a product’s ingredients must the meet standards for organic labeling, White says.

The ‘Non-GMO Project‘ seal, meanwhile, indicates a manufacturer has undergone a voluntary third-party verification process to confirm it’s free of GMO ingredients.

Consider How You Feel About ‘Proprietary Blends’

The terms ‘blend,’ ‘complex,’ ‘matrix,’ or ‘proprietary formulation’ may sound cool on a supplement label, but you may want to tread carefully. These terms often indicate a supplement contains a ‘proprietary blend,’ or a specific and unique combination of ingredients.

What’s the problem? Normally, the FDA requires supplement manufacturers to list all product ingredients on the supplement label (along with the amount of each according to weight). However, ‘proprietary blends’ are an exception, according to Operation Supplement Safety, a dietary supplement resource from the Department of Defense.

Manufacturers only have to list the total amount of proprietary blends, so they can effectively hide the amounts of specific ingredients, White says.

Read More: How To Tell If That Supplement You Bought Online Is Fake

For example, say an ‘antioxidant blend,’ contains a total of 1,118 milligrams of ingredients like organic acai and maca. “You have no idea how much of each individual ingredient is in the product,” White explains.

Some manufacturers patent proprietary blends to prevent other companies from selling the same product, White says. However, this doesn’t necessarily mean a proprietary blend is more effective.

Ultimately, not knowing how much of a specific ingredient your supplement contains could be problematic, says White. If you’re sensitive to stimulants, for example, you’ll want to know exactly how much a supplement contains.

Look for ‘Full Disclosure’ Labels

If you’re not into the idea of proprietary blends, look for ‘full disclosure’ labels, which list the exact doses of every ingredient in a product, recommends Jessica Crandall Snyder, R.D., C.D.E., founder of the nutrition, fitness, and wellness services company Vital R.D.

These labels often eliminate the guesswork involved in taking a supplement that contains proprietary blends. The result: You have a crystal-clear understanding of what you’re consuming.

When In Doubt, Work With A Dietitian

If you want to add a supplement to your routine but aren’t sure where to start, check in with a dietitian. They can help you figure out what types of supplements (and how much) you really need—and can steer you toward high-quality options. 

The Vitamin Shoppe offers free virtual consultations with its nutritionists to all Healthy Awards members. Learn more here.

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