With dietary supplements, as with other consumer products, there are brands that use only the best ingredients, brands that use good ingredients, and brands that use the cheapest ingredients. Here’s some information that should help consumers and practitioners identify and choose between these options.
Nutraceuticals Are Dietary Supplements. A product labeled “nutraceutical” isn’t necessarily the best or even a good product. In the United States, nutraceuticals have no legal standing—they are dietary supplements. More important than the category “nutraceutical” is the publicly available data on its safety and benefits for human health.
Natural Isn’t Necessarily Better Than Synthetic. I’ve seen assertions online that chemicals are bad for the body and that supplement ingredients should come directly from nature, without processing or alteration. This is misinformation and potentially detrimental to consumers. The fact is, our bodies run on chemicals.
Our human life processes are based on transformations of chemicals. We use enzymes (chemical catalysts) to break down food into chemicals, which are then used by other enzymes for energy, tissue maintenance, growth, and repair. Whether a supplement ingredient is obtained directly from nature or from a chemical synthetic process, it can be identical to the molecule the body needs.
Take, for example, vitamin C—ascorbic acid (AA). Since the body can’t make it, our entire supply must come from diet or supplements. High-purity AA can be extracted from plants, produced from bacteria or fungi through fermentation, or processed from glucose in a manufacturing plant. Each method can produce highly pure AA.1Susa FR, Pisano R. Advances in ascorbic acid (vitamin C) manufacturing: green extraction techniques from natural sources. Processes. 11(11):3167. https://doi.org/10.3390/pr11113167
Organic Ingredients Must Still Be Tested. Ingredients classified as “organic” are obviously preferable over nonorganic ingredients in dietary supplements. Many herbal ingredients now come in two forms: regular and certified organic. Organic ingredient forms are more expensive. Regardless, the FDA requires that supplement manufacturers test all ingredients to verify they are free of contamination, regardless of their country of origin or certified organic status.
Good and Bad Ingredients Can Originate Anywhere. Another area of confusion and misinformation stems from the notion that some countries, especially the United States, make better supplement ingredients than others. However, ingredient quality hinges on the competence and business ethics of the teams that produce them. No matter how stringent a government’s regulations may be, skilled chemists can (and do) find ways around them.
Bad (and good) ingredient producers aren’t limited to any country. This is why it’s so important that supplement manufacturers test ingredients as much as necessary to verify their quality. The FDA encourages onsite audits of suppliers.
How to Identify the Ingredients in a Supplement

First, look at the center panel of the label, which should clearly state “Dietary Supplement.” If this is missing, the product might not be legal. Next, go to the Supplement Facts panel to see the active ingredients. It should disclose the serving size, servings per container, and amount per serving for each ingredient.
Each ingredient listed in the Supplement Facts panel should have a stated dose per serving and % Daily Value (%DV), which is the U.S. government’s recommended minimum daily intake. Ingredients without an assigned Daily Value should have a “†” symbol in the %DV column.
Directly below the Supplement Facts should be the Other Ingredients list, which should include all ingredients not in the Supplement Facts. These may include artificial colorants (dyes)—many of which have questionable safety, even though they are classified as safe by the FDA. Savvy manufacturers will use safe, naturally colored food powders such as spirulina (a beneficial blue–green alga), beetroot, or turmeric.
Three additives that substantially improve manufacturing efficiency—microcrystalline cellulose, silicon dioxide, and magnesium stearate—may also be listed as Other Ingredients. I’ve delved thoroughly into the chemistry, safety, and tolerability of these additives for sensitive individuals and have found no reason to recommend against their use.
What Is a Good Dietary Supplement Ingredient?
A good supplement ingredient is tested by the manufacturer before being combined with other ingredients to create the final product. The distributor, whose name appears on the packaging, has the right to obtain from the manufacturer all data on the ingredient’s identity, strength (potency), composition, and purity, along with the test methods used to obtain this data.
Regardless of whether the ingredient is registered by the FDA (as mandatory registration requirements are not yet finalized), a good supplement ingredient should undergo thorough verification for long-term safety through well-defined toxicology testing. If you are concerned, request proof of safety from the company whose contact information is on the packaging.
A good dietary supplement ingredient has published human data to support its health claims. This is an FDA requirement. These data should be available in scholarly journals that employ peer review, a pre-publication evaluation of the article by experts competent in that area of research who are not financially connected with the researchers.
The good ingredient category can include synthetic (manufactured) ingredients that are chemically identical to the naturally occurring versions, given that they do not contain potentially harmful byproducts of the manufacturing process. Vitamin C is a standout example. Suppliers of good ingredients typically don’t try to hide behind sloppy science.

Bad Supplement Ingredients

The dietary supplement industry has its share of unscrupulous players pushing bad ingredients. I consider an ingredient “bad” when it doesn’t have proven contributions to human health and poses any likelihood of harm.
So-called “nootropics” or “cognitive enhancers” are being marketed as dietary supplements to students and other young, healthy people trying to squeeze more mental performance out of their brains. Yet, many of these ingredients are drugs not approved for sale in the United States. A prominent example is piracetam and other “racetam” drugs, which are not proven to enhance mental performance in healthy adults.
Piracetam can interfere with platelet function and should not be taken with antiplatelet or other anticoagulant drugs. Other possible adverse effects of piracetam include gastrointestinal disturbances (like constipation), hypertension, rash, and weight gain. It should be avoided during pregnancy, with epilepsy, kidney problems, Huntington’s disease, or if a person has a cocaine addiction.2Piracetam. NatMed: Therapeutic Research Center. Accessed July 2024. https://naturalmedicines.therapeutic research.com
Some sexual “performance enhancing” ingredients are dangerous, besides being illegal. The bark of the Yohimbe tree contains yohimbine. Even though they have not been proven effective, natural yohimbine and manufactured yohimbine are sold in dietary supplements and can have adverse effects, such as increased heart rate, hypertension, seizures, headache, nausea, tremors, and insomnia.3Yohimbe. National Center for Complementary and Integrative Health. Updated November 2020. https://www.nccih.nih.gov/health/yohimbe
Many supplements contain ingredients that aren’t active for the claimed benefits but are included purely for cosmetic reasons—to make the product look or feel better. These include potentially harmful artificial colorants like FD&C Red Nos. 3 and 40, Yellow 5 and 6, Green 3, and Blue 1 and 2. Some dyes may promote cancer; others trigger hyperactivity in kids.4Kobylewski S, Jacobson MF. Food dyes: a rainbow of risks. Center for Science in the Public Interest. Published 2010. https://www.cspinet.org/sites/default/files/attachment/food-dyes-rainbow-of-risks.pdf In 2022, the European Union banned titanium dioxide as a food whitener due to concerns about its safety when ingested.
Best Supplement Ingredients
I find that the best ingredients not only have precise technical specifications but also the support of excellent clinical research published in peer-reviewed scientific publications. Currently, standardized herbal extracts lead the way. Their chemical diversity is expanding even as the clinical evidence for health benefits continues to grow.
Standardization of an herbal extract involves focusing on specified active substances to ensure their content in the extract has minimal variation. This ensures the consumer will experience consistent benefits (and safety) from batch to batch. The finished product’s label should show the amount of the standardized active ingredient(s) provided per serving.
Herbals with the foremost standardized extracts include ashwagandha (Withania somnifera), maritime pine (Pinus pinaster), turmeric (Curcuma longa, source of curcumins), saffron (Crocus sativus), fenugreek (Trigonella foenum–graecum), and tongkat ali (Eurycoma longifolia). When choosing a standardized extract, it’s crucial to examine its specific clinical track record.
Different standardized extracts from the same herbal can produce very different benefits, and some extracts may not work at all. Suppliers of the best extracts are sometimes victimized by other suppliers, who “borrow” their published data, asserting that the data was generated by their products.
The best dietary supplement ingredients are likely the most chemically defined, most free of contamination (including from industrial processing), and supported by well-designed clinical trials that establish their specific safety and health benefits.
Distinguishing Between Good, Bad, and Best Ingredients
Testing is the key—specifically, high-powered chemical analysis, conducted by independent, third-party laboratories. Berberine has been getting a lot of attention (and sales) for its weight loss potential. In 2023, as part of an ongoing evaluation of questionable products, the NOW Health Group purchased 33 brands of berberine and sent them to third-party Alkemist Labs for testing. The results were terrible.5NOW’s testing results of berberine products December 2023. NOW Foods. Published December 2023. Accessed July 2024. https://www.nowfoods.com/healthy-living/articles/nows-testing-results-berberine-products-december-2023
Using sophisticated, high-performance liquid chromatography to measure berberine, Alkemist found 32 of the 33 brands below 100 percent of the amount stated on the label (“potency”). Three tested at 90 to 97 percent potency; 18 tested at less than 40 percent potency; and 7 had 1 percent potency or less. Alkemist and NOW Health have tested other ingredients in products from these same brands with the least potency and found similar problems.6Sherman A. NOW testing program reveals ‘alarming quality failings’ of berberine products online. NutraIngredients-USA. Published December 2023. Accessed July 2024. https://archive.is/alz6U
The FDA has been informed of potency levels for ingredients in widely available products.6Sherman A. NOW testing program reveals ‘alarming quality failings’ of berberine products online. NutraIngredients-USA. Published December 2023. Accessed July 2024. https://archive.is/alz6U Despite this, they seemingly haven’t taken steps to bring offending brands into compliance. There really should be consequences for these lapses. People might wonder if the brands have designated quality control personnel, as required by FDA regulations.
Using poor ingredients or insufficient amounts of good ingredients in dietary supplements not only cheats consumers but also risks negative consequences for the manufacturer. If nothing else, using high-quality ingredients ensures reliability. Using the best ingredients enhances the power of supplements to improve people’s lives.
Footnotes
- 1Susa FR, Pisano R. Advances in ascorbic acid (vitamin C) manufacturing: green extraction techniques from natural sources. Processes. 11(11):3167. https://doi.org/10.3390/pr11113167
- 2Piracetam. NatMed: Therapeutic Research Center. Accessed July 2024. https://naturalmedicines.therapeutic research.com
- 3Yohimbe. National Center for Complementary and Integrative Health. Updated November 2020. https://www.nccih.nih.gov/health/yohimbe
- 4Kobylewski S, Jacobson MF. Food dyes: a rainbow of risks. Center for Science in the Public Interest. Published 2010. https://www.cspinet.org/sites/default/files/attachment/food-dyes-rainbow-of-risks.pdf
- 5NOW’s testing results of berberine products December 2023. NOW Foods. Published December 2023. Accessed July 2024. https://www.nowfoods.com/healthy-living/articles/nows-testing-results-berberine-products-december-2023
- 6Sherman A. NOW testing program reveals ‘alarming quality failings’ of berberine products online. NutraIngredients-USA. Published December 2023. Accessed July 2024. https://archive.is/alz6U