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Fullscript ensures safety, effectiveness, and a convenient experience. Products in the Fullscript catalog are enforced with strict quality controls to ensure what’s on the label is in the bottle.
Dietary Supplement Quality Assurance
When shopping for supplements, you may wonder which brand or product is the best choice. This decision is often personal and should take into consideration the recommendations from your integrative practitioner. No matter the type of supplement you choose, it’s best to select high-quality products from reputable brands.
How can you determine whether a supplement is high-quality? According to the Food and Drug Administration (FDA), a quality product “consistently meets the established specifications for identity, purity, strength, and composition, and (limits on) contaminants, and has been manufactured, packaged, labeled, and held under conditions to prevent adulteration.” (20)
Purchasing your supplements from a trusted source can help ensure you’re using safe, high-quality products. Outlined below are several quality factors to consider when purchasing supplements.
Dietary Supplement Regulation
The FDA and Health Canada are the primary government agencies responsible for overseeing dietary supplements and natural health products in the United States and Canada; however, these products are regulated as food products, not as drugs. (36)(60)(63)
The FDA and Health Canada have established baseline quality standard regulations for dietary supplements’ safety, efficacy, and quality. (12)(35) For example, the U.S. FDA and Canadian Health Products and Food Branch Inspectorate (HPFBI) enforce the Current Good Manufacturing Practices (cGMPs), also referred to as GMPs, which is a set of requirements outlining several standards for manufacturing, packaging, labeling, storage, distribution, and recall procedures. GMPs also involve routine testing of products to ensure that they contain the ingredients indicated on the label and are free of contaminants. (11)
Did you know? A 2013 report published by the FDA determined that 70% of supplement manufacturers violated GMPs. (49)
In the United States, supplement regulation is not as strict as the regulation of pharmaceutical medications. This means that supplement manufacturers are not required to meet the same quality and safety standards as pharmaceuticals or undergo routine testing. As a result, some supplements lack transparency for purity, quality, and safety.
Many reputable supplement manufacturers establish their own strict standards and manufacturing processes, often with oversight from third-party certifiers, to provide additional transparency to consumers. Supplements produced without purity, quality, and safety standards are at a greater risk of cross-contamination and other issues affecting consumer health. The product may also include expired ingredients or may display an inaccurate label. (60)
Ingredient Sourcing
Do you know what’s in your supplement? You may be surprised to learn that many supplements contain misidentified or adulterated ingredients that could pose a risk to consumers. Without proper identification and validation of ingredients included in a health supplement, it’s difficult to determine the quality, safety, or efficacy of a product.
Products with poor quality standards may contain mislabeled ingredients or unsafe substances, including:
- Adulterated ingredients
- Biological contaminants (e.g., mold, bacteria)
- Illegal substances
- Ingredients not indicated on the label
- Heavy metals
- Herbicide or pesticide residues (71)
To ensure that you’re using the safest and highest quality supplements, select products from distributors that are transparent about their ingredient sources and harvesting methods, especially when selecting products containing plant-derived components (botanicals). (85) For products containing synthetic ingredients, look for brands that provide information on their extraction and purification methods, both of which can significantly alter the bioavailability and efficacy of the product. (81)
Ingredient Absorption and Bioavailability
Another important consideration for all types of supplements is ingredient absorption and bioavailability. (70) A supplement’s bioavailability, or the amount of the active ingredient absorbed by the body, is influenced by several factors.
Delivery Form
Supplements may be better suited for specific delivery forms (e.g., table, capsule, enteric-coated, emulsion) to improve user experience and to optimize absorption and bioavailability based on their characteristics, such as stability, and release time (e.g., sustained-release melatonin). (21)
Dose
The dosage of some supplements can influence the rate of absorption. For example, once certain levels of water-soluble vitamins (e.g., vitamin C, B vitamins) reach a maximal level, excess vitamins are excreted via the kidneys. (46) It’s important to note that supplement dosages are recommended by the manufacturer as there are no standard dosages for supplement ingredients. However, many professional brands determine recommended dosages based on results from clinical trials. (79)
Formulations
Some manufacturers have developed patented formulation technologies to enhance absorption and bioavailability of their product, such as trademarked forms of curcumin, Meriva™ and BCM-95™. (37)
Supplement Carriers/Vehicles
Carriers, or ingredients used to assist supplement delivery, are used to improve bioavailability for some health supplement ingredients. For example, vitamin D supplements and other fat-soluble vitamins are often combined with a carrier ingredient, such as oil or ethanol (alcohol). (31)
Third-Party Certifications
Many reputable manufacturers demonstrate dietary supplement quality assurance by voluntarily utilizing third-party certifiers. There are dozens of third-party companies that offer certifications to ensure that manufacturers are meeting certain quality standards. Products that have been certified by a third-party company will typically display a certification emblem on the label.
Common third-party certifications include:
- Certified Gluten-Free (30)
- Certified Organic (USDA Organic, Canada Organic) (10)(77)
- Certified Vegan (80)
- National Sanitation Foundation (NSF) (56)
- Non-GMO Project Verified (74)
- U.S. Pharmacopeia (USP) (75)
Product Manufacturing
How a product is manufactured, stored, and distributed is equally important as its contents. Choose products from manufacturers that are transparent with their manufacturing processes and use independent third-party certifiers to verify that the manufacturer is meeting specific standards. When purchasing supplements, it’s important to consider products produced by cGMP-compliant manufacturers. Additionally, purchasing from distributors with cGMP-compliant warehouses ensures that supplements are stored at proper temperatures and humidity levels.
Some manufacturers will provide lab reports and Certificates of Analysis (CoA) to confirm that a product meets predetermined standards and specifications. In other words, a CoA ensures that a supplement’s constituents are accurately represented on the label. (44) Manufacturers that provide CoAs often include this information on their website or it can be obtained by contacting the manufacturer directly.
Allergens
The labeling of allergens and claims related to the sourcing of supplement components is an important consideration, particularly for individuals with allergies. In 2004, the FDA introduced the Food Allergen Labeling and Consumer Protection Act (FALCPA) which requires that supplement labels disclose if the product contains any of the top eight allergens, which include milk, eggs, fish, crustacean shellfish, tree nuts, wheat, peanuts, and soy. (13)
Additionally, labels must include information about any added flavoring, coloring, or additives. Unfortunately, the FALCPA doesn’t require companies to include “may contain” statements that can result from cross-contamination through the manufacturing process. (13)
Did you know? Approximately 10% of adults and 8% of children have a food allergy.
Contaminants, Banned Substances, and Excipients in Supplements
Excipients, or inactive ingredients, are often added to supplements and pharmaceuticals to improve the manufacturing process or the stability, taste, texture, or physical appearance of a finished product. (15)(29) Excipients in supplements are similar to food additives in food products and can be derived naturally or synthetically. (75) These additives are regulated by the FDA and must comply with a regulation known as “Generally Recognized as Safe” (GRAS). GRAS ingredients are considered safe by experts when used as directed. (14) While a product’s ingredients may be considered safe, they may pose a risk to individuals who are allergic or sensitive to certain ingredients. Other common adverse reactions associated with excipients include gastrointestinal upset and skin reactions. (4)(66)
Examples of common excipients in supplements include:
- Ascorbic acid
- Aspartame
- Carrageenan
- Lactose
- Lecithin
- Magnesium stearate
- Polyethylene glycol
- Polysorbate 80
- Stearic acid (15)
Contaminants, such as mold, bacteria, and heavy metals, can also find their way into supplements, particularly in poor-quality products that are not regularly inspected by third-party certifiers. Search for products that undergo routine inspections and testing to ensure they are free of harmful contaminants.
The United States Anti-Doping Agency (USADA) and the World Anti-Doping Agency (WADA) have established a list of prohibited substances in dietary supplements known to enhance athletic performance. Competitive athletes should use caution when selecting supplements from resellers as they can potentially contain banned ingredients. (49) Look for products that have been analyzed by third-party certifiers, such as NSF Certified for Sport, Informed Choice, and Informed Sport. (45)(55)
The FDA also maintains a Tainted Supplements List, which outlines over 1,000 products known to contain hidden and potentially harmful ingredients. Many of the products included in the FDA’s list are commonly marketed for weight loss, bodybuilding, or sexual enhancement purposes. (78)
Counterfeit Supplements
Supplements can be purchased from numerous brick and mortar stores and online retailers; however, some resellers are at increased risk of poor storage practices, illegitimate product labeling, and counterfeit supplements. Additionally, many resellers don’t have formal processes in place for handling quality control, product recalls, or adverse reactions. For these reasons, it’s important to select supplements from reputable sources.
Numerous investigations have uncovered cases of counterfeit supplements sold at major retailers. According to one investigation, four out of five products taken from shelves of GNC, Target, Walgreens, and Walmart did not contain any of the herbs indicated on the product’s label. Instead, the products contained fillers with no therapeutic effects. (57) Another major supplement reseller, Amazon, is particularly vulnerable to counterfeit supplements because they rely on third-party resellers. In 2019, Amazon warned its customers that a particular supplement sold by third-party resellers on their site was likely fake and therefore unsafe to consume. (33)
What Are Dietary Supplements Used For?
Supplements may be recommended for various reasons based on an individual’s needs, such as to ensure an adequate intake of nutrients, promote optimal health and performance, or achieve a desired health outcome. (61) While a balanced diet, which incorporates a variety of nutrient-dense foods, ideally provides all the essential nutrients needed to support body functions and health, there are many factors that may affect individual nutrient status and supplementation needs.
These factors, which are related to food and diet quality as well as the health status of each individual, include:
- Decreased nutrient levels in foods due to modern agriculture (22)(23)
- Impaired digestion and absorption (9)
- Increased requirements during certain periods (e.g., adolescence, pregnancy, lactation) (9)
- Low dietary intake and/or poor quality diet (32)
- Nutrient depletions associated with medications (e.g., oral contraceptives, proton pump inhibitors, statins) (51)
- Nutrient loss occurring as a result of aging or critical illness (9)