When it comes to you and your family, you want only the best. Unfortunately, you cannot trust all vitamin supplements to be high quality. Four out of five herbal supplements tested at Wal-Mart, Target, Walgreens, and GNC contained none of the medicinal herb that was printed on the label and instead contained cheap fillers like rice powder, asparagus, and houseplants. 46% of popular US multivitamins didn’t contain what was stated on the label and 80% of gummy vitamins failed quality tests. Nutritional supplements can even be contaminated with lead, causing more harm than good. And if you buy probiotics or other supplements on Amazon, they could be counterfeit or expired.

Do you want the highest quality supplements for your family, at clinically effective dosages, without any contaminants or harmful ingredients?

You’re not alone. Almost 70% of Americans take supplements such as vitamins, probiotics, fish oil, botanical medicine, and more. The $115 billion dollar supplement industry has exploded in the last 25 years. Nutritional supplements are not heavily regulated like pharmaceutical medications because they are considered food, not medicine.*

The FDA requires that dietary supplements are produced with current good manufacturing practices (cGMPs) and contain the ingredients listed on their labels. But it doesn’t test them to make sure that is happening. The FDA can investigate and prosecute unsafe or fraudulent products after they are on the market, but enforcement has been inconsistent.

And while there are third party testing organizations that oversee supplement quality, it’s not mandatory. Plus, it costs money. That means it falls on the manufacturers’ shoulders to ensure quality – or not.

The hundred-billion dollar supplement industry has unfortunately attracted people who want to make a buck, instead of look out for your health and safety.

Supplements can be fake, laced, cut, expired, damaged, contaminated, or rancid.

The lack of oversight and the booming supplement industry means that you need to protect yourself and your family when shopping for supplements.

Disclaimer: Little did I know what I was getting into when I started a blog on supplement quality! Even I didn’t know what actually set practitioner-exclusive supplements apart. With 20 years of experience as a nutraceutical scientist, working in a health food store, and working in the integrative and functional medicine world, the topic of supplement quality was incredibly complex and took me hours of research! If it’s this difficult for me, how can a normal consumer understand supplement quality? The information I present here is accurate to the best of my knowledge at the time of this writing. I welcome comments and corrections. Also, the recommended supplement brands below are based in part on the companies’ websites. If a company website omits relevant quality information, then it will be reflected in the recommended supplements lists below. This is by no means an exhaustive list of supplement companies.


  • Toxins/contaminants. Nutritional supplements, which don’t require 3rd party testing, may not actually contain what is listed on the label. Raw materials may be contaminated with potentially harmful ingredients.
  • Counterfeit. It is painfully easy for an imposter to mimic a high quality supplement brand and sell it to consumers as the real thing.
  • Adulterating. Sellers may lace supplements with drugs that are dangerous. Or they might cut them with harmless, but useless, ingredients. The FDA has a long list of tainted supplements.
  • Poor Storage Conditions. Nutritional supplements are sensitive to heat and moisture and they expire. Warehouse conditions (such as at Amazon) may be extreme, causing the supplements to deteriorate. A supplement might be sold, returned, and resold, without proper storage or tracking.
  • Tampered Products. Sellers can take expired supplements and put a new label on them for resale or rub off identifiers such as lot numbers and bar codes that help guarantee efficacy.


Don’t settle for grocery store quality supplements

If you want the best quality vitamin D, B vitamins, probiotics, or fish oil, you will not find it at the grocery store. There are two kinds of nutritional supplements on the market: grocery store supplements or professional-only supplements.

Grocery store supplements. These dietary supplements are sold directly to consumers at the grocery store, drug store, or health food store. These brands are not well-known for exceedingly high standards of quality, although they may have high quality. They may contain unnecessary ingredients that make it easier to mass produce supplements, but that aren’t really good for you. Grocery store supplement brands can pay for 3rd party testing to ensure high quality, but it is optional. Therefore, they may not contain what is stated on the label or they may contain unknown or even harmful ingredients. See recommended grocery store brands below. And as I mentioned above, the FDA is not consistently testing supplements to make sure of any of this.

Professional-only supplements (a.k.a. practitioner-exclusive supplements). These supplements are carefully manufactured, rigorously tested, and known for superior quality, purity, and efficacy. Historically, these brands were sold exclusively through licensed healthcare practitioners. However, some are beginning to sell directly to consumers (see DaVinci Laboratories and Designs for Health in the recommendations below). Professional-only supplement companies are regarded as the best quality supplements in the integrative and functional medicine industry. But remember, just like all supplements, they aren’t consistently tested by the FDA to confirm their quality claims.

Here are some of the things you can look for from professional-only supplements:

  • The supplement meets the FDA regulatory standards for pharmaceutical safety and efficacy, known as Current Good Manufacturing Practices (cGMP)
  • Follows USP standards
  • Careful selection of raw materials supplier
  • Third party independent lab testing
  • In-house laboratory testing
  • Testing for purity and contaminants
  • Testing of raw materials
  • Testing of finished products
    • To verify that the ingredients inside the bottle match the ingredients on the label
    • To verify the potency of the ingredients
  • Control of the entire manufacturing process
  • Free of allergens, fillers, binders, excipients, dyes, and unknown substances
  • Trusted by licensed healthcare practitioners, who treat some of the most allergic and sensitive chronically ill patients

When it comes to trusting your supplements, professional-only supplements are a much safer bet.

But the quality of a nutritional supplement depends on the integrity of the manufacturer and its financial commitment to quality. That’s why I recommend seriously researching the supplement company you use (see recommended supplements below). For people who can’t access professional-only supplements, grocery store nutritional supplements that have the USP verified mark on the label seem to be high quality. I list a few recommended brands that meet that criteria at the end of this blog.

Dos and Don’ts Guide to High-Quality Nutritional Supplements

The Dos:

  • DO buy professional-only supplements.
  • DO buy from a trusted healthcare provider, who has researched supplement quality and has a relationship with multiple supplement manufacturers.
  • DO buy directly from a legitimate manufacturer (see DaVinci and DFH examples below). If there are middle-men in the supply chain, there are more chances for product damage or fraud.
  • DO look for products manufactured according to FDA’s current Good Manufacturing Practices (cGMP). cGMPs are the FDA regulatory standards for pharmaceuticals for safety and efficacy. They apply to all nutritional supplements in the industry. Following good manufacturing processes means every step of the manufacturing process is documented and guided by standard operating procedures. The supplements are made in a clean and sanitary facility that is in good condition. Equipment is properly maintained, employees are qualified and trained, and there are reliable and reproducible processes in place to prevent contamination, mix-ups, errors, failures, or poor quality deviations. Facilities may be audited by the FDA. Following cGMPs is a minimum standard for quality and many professional-only supplement companies self-impose even higher standards.
  • DO look for products that manufacture according to U.S. Pharmacopeia (USP) standards. USP is a globally recognized, non-government, non-profit organization that sets widely accepted standards for pharmaceuticals and nutritional supplements: identity, potency, and purity. By federal law, pharmaceuticals and over-the-counter drugs must meet USP standards, but it’s optional for supplement companies. If a supplement label says “USP” then it is claiming to follow USP standards.
  • DO look for supplements that have undergone 3rd party independent testing. A high-quality supplement company will use a 3rd party watchdog to monitor its quality. Examples of these are USP, NSF International, UL, com, Eurofins, Sillikier, Covance, Advanced Laboratories, Alkemist, Diteba, International Fish Oil Standards Program, International Krill Oil Standards Program, and Australian Therapeutic Goods Administration. The Natural Products Association has a 3rd party GMP certification program for supplement companies.

  • DO look for the USP Verified Mark on the label, a distinctive black and gold seal. USP has a third party testing program for dietary supplements, apart from its role in setting standards for drugs and supplements (above).

                   The USP Verified Mark on the label indicates that the product:

    • Contains the ingredients listed on the label, in the declared potency and amount
    • Does not contain harmful levels of specified contaminants
    • Will break down and release into the body within a specified amount of time
    • Has been made using safe, sanitary and well-controlled manufacturing practices according to FDA and USP guidelines


  • DO research the supplement company. Make sure they are a reputable company, have contact information, and a customer service number. Look for their “Quality” webpage to make sure they are serious about quality, how they verify their it, and if they use 3rd party testing.
  • DO look for your desired supplement on ConsumerLab.com, which independently tests supplements and reports quality ratings by brand (access costs $3.95/month).
  • DO look for companies who say they test their raw ingredients and their finished products.
  • DO look for companies who control the entire manufacturing process A to Z.

The Don’ts


  • DON’T buy grocery store supplements unless you have researched and verified the company’s quality program.
  • DON’T buy supplements online. Do not buy vitamins and supplements from Amazon or eBay, unless you can be sure you are buying directly from the manufacturer on Amazon (see DaVinci example below). Amazon cannot easily identify counterfeiters and they are infamous for poor warehouse conditions.
  • DON’T buy from middle-men in the supply chain (e.g. third parties on Amazon); there are more chances for product damage or fraud.
  • DON’T buy cheap supplements. High-quality nutritional supplements cost real money (to produce and to test). Beware of cheap supplements. They could be counterfeit, cut, or expired.
  • DON’T buy supplements without an expiration date.
  • DON’T buy supplements from companies that don’t have a Quality web page. If they are really committed to quality, wouldn’t they say so?


So, What to Buy?

Here is a list of professional-only supplement companies, many of which are also recommended in Dr. Jill Carnahan’s excellent blog on the topic. All of the supplement companies listed here had substantial web pages on quality control. They boast careful selection of raw materials/suppliers, FDA audits of their facilities, third party testing, control of the entire manufacturing process, in-house laboratories, testing of raw ingredients, testing of finished products, extensive testing for contaminants, and/or products that are free of allergens, binders, excipients, fillers, and unknown substances. Some of these companies are involved in clinical trials testing their products. Companies that mention a specific third party independent testing laboratory on their site are marked with **.

Recommended Professional-only Supplements


Recommended Grocery Store Supplements   

With the USP Verified Mark on the Label

With Specific 3rd party testing

Popular Brands Not Recommended Because of Weak Quality Web Pages and No Mention of 3rd Party Testing

  • New Chapter
  • Solaray
  • KAL
  • Pure Synergy
  • Standard Process
  • Puritan’s Pride
  • Vitamin Shoppe

Finding High-Quality Vitamins, Probiotics, and Fish Oil Supplements

Nutritional supplements contain food ingredients and are generally thought to be a healthy alternative to prescription medications. But not all supplements are created equal and the supplement industry is still the wild west. Use these tips to shop for vitamins, fish oil, probiotics, and more supplements that are safe, pure, and the highest quality for you and your family. Professional-only supplements are regarded as the highest, best quality. Above all, buy your supplements from a trusted practitioner or from a legitimate manufacturer, cutting out middle-men. Do your research to make sure the company you’re buying from deserves your hard-earned dollars and that what you and your family put in your bodies is healthy and safe. 

Free, Customizable, One-Page Handout for Patients

Do you want all of these tips in one place? If so, check out the “Buyer’s Guide to High-Quality, Safe, Nutritional Supplements for You and Your Family.” Download the handout for free, add your company logo, and edit it as you see fit. Your patients need to know why buying supplements online or at the grocery store isn’t a great idea.

 This one-page handout covers these topics:

  • Dos and Don’ts Guide to High-Quality Supplements
  • Problems with low-quality supplements
  • FDA regulation of nutritional supplements
  • Professional-only supplements
  • Grocery store supplements

*The Dietary Supplement Health and Education Act of 1994 said that supplements were food products and not drugs, and are therefore not subjected to the same scrutiny as pharmaceutical drugs.


Cass Nelson-Dooley, M.S.

Cass Nelson-Dooley, M.S.

Cass Nelson-Dooley, MS, is a researcher, author, educator, and laboratory consultant. She studied medicinal plants in the rain forests of Panama as a Fulbright Scholar and then launched a career in science and natural medicine. Early on, she studied ethnobotany, ethnopharmacology, and drug discovery at the University of Georgia and AptoTec, Inc. She joined innovators at Metametrix Clinical Laboratory as a medical education consultant helping clinicians use integrative and functional laboratory results in clinical practice. She owns Health First Consulting, LLC, a medical communications company with the mission to improve human health using the written word. Ms. Nelson-Dooley is an oral microbiome expert and author of Heal Your Oral Microbiome. She was a contributing author in Laboratory Evaluations for Integrative and Functional Medicine and Case Studies in Integrative and Functional Medicine. She has published case studies, book chapters, and journal articles about the oral microbiome, natural medicine, nutrition, laboratory testing, obesity, and osteoporosis.