How are dietary supplements defined NASM?

December 1, 2025 •

3 min read

According to the National Academy of Sports Medicine (NASM), dietary supplement usage is extremely common, especially among fitness enthusiasts. Understanding precisely how are dietary supplements defined NASM is critical for certified professionals to operate within their legal and ethical scope of practice.

Quick Summary

A NASM-certified professional relies on the DSHEA definition of dietary supplements, which includes various products like vitamins, minerals, and botanicals intended to augment the diet, not replace conventional foods.

Key Points

DSHEA Alignment: NASM's definition of a dietary supplement aligns with the Dietary Supplement Health and Education Act of 1994 (DSHEA).
Ingredient Types: Supplements are products containing ingredients like vitamins, minerals, herbs, and amino acids.
Ingestion Forms: They are intended for ingestion in forms like pills, capsules, and liquids, and are specifically labeled as dietary supplements.
Not Food or Drugs: A key distinction is that supplements cannot be marketed as conventional food or as a treatment for disease, and are not regulated as drugs.
Educate, Don't Prescribe: NASM-certified professionals are ethically bound to educate clients on supplement safety and efficacy, not to prescribe specific supplements or dosages.
Prioritize Whole Foods: NASM's philosophy prioritizes nutrient-dense foods as the primary source of nutrition, with supplements used to fill identified dietary gaps.
Refer to Experts: When faced with complex client questions or health conditions, certified professionals must refer clients to registered dietitians or physicians.

Understanding the NASM Definition of Dietary Supplements

When asking how are dietary supplements defined NASM, it is important to recognize that the academy's definition is directly aligned with the legal framework established by the Dietary Supplement Health and Education Act (DSHEA) of 1994. This foundational understanding guides certified professionals in what they can and cannot recommend to clients. NASM emphasizes that a dietary supplement is a substance intended to complete or make an addition to a person's daily dietary intake. This differentiates it from conventional food and pharmaceuticals, which are regulated differently.

Core Criteria of a Dietary Supplement

According to NASM's educational materials, a product must meet several specific criteria to be classified as a dietary supplement under DSHEA. These include being a product (excluding tobacco) intended to supplement the diet, containing one or more dietary ingredients like vitamins, minerals, herbs, or amino acids, and being intended for ingestion in forms such as a pill or liquid. It cannot be represented as a conventional food or the sole item of a meal or diet and must be labeled as a 'dietary supplement'.

The NASM Scope of Practice Regarding Supplements

For any fitness or nutrition professional, understanding the boundaries of their certification is essential, especially with dietary supplements. NASM training distinctly outlines a clear scope of practice for its Certified Personal Trainers (CPTs) and Certified Nutrition Coaches (CNCs). Professionals are trained to provide general, evidence-based education about supplementation, including discussing potential benefits and risks, and how to read labels. NASM explicitly states that its certified professionals should not prescribe specific supplements or dosages to clients. When clients have specific health conditions, complex nutritional needs, or medical questions about supplements, the NASM professional must refer them to a registered dietitian (RDN), physician, or other qualified medical professional.

What is not a dietary supplement?

Based on DSHEA and NASM's curriculum, a product is not a dietary supplement if it is approved as a new drug or biologic, or if it is marketed as a conventional food. The Food and Drug Administration (FDA) is responsible for overseeing the supplement industry, though it does not approve supplements for safety or effectiveness before they are sold; manufacturers are responsible for ensuring safety and accuracy in labeling.

Comparing Dietary Supplements and Conventional Foods

This table outlines the key differences between dietary supplements and conventional foods from a regulatory and educational perspective, as taught by NASM.


Feature	Dietary Supplement	Conventional Food
Primary Purpose	To supplement or add to the daily diet.	To provide a meal or conventional food item.
Form	Tablets, capsules, powders, liquids, etc..	Solid food, beverages, snacks, etc..
Labeling	Must be labeled a 'dietary supplement' with a Supplement Facts panel.	Features a standard Nutrition Facts label.
Regulation	Regulated by FDA, but not pre-approved. Manufacturers are responsible for safety and claims.	Regulated by FDA with stricter pre-market approval processes for additives and claims.
NASM Professional's Role	Provide general, evidence-based education; refer out for specifics.	Discuss healthy eating strategies, portion sizes, and food sources.

Adhering to Responsible Supplement Use

Responsible supplementation is a core tenet of NASM's nutrition philosophy. Clients should be encouraged to prioritize a nutrient-dense whole foods diet first, addressing any dietary gaps with supplements only if necessary. NASM professionals emphasize checking labels for a fully disclosed list of ingredients and avoiding proprietary blends where dosages are unknown. Furthermore, clients should always consult with a healthcare provider before starting a new supplement, especially if they have underlying health conditions or are taking medication.

Conclusion

For a NASM-certified professional, understanding how are dietary supplements defined NASM means recognizing the legal and ethical boundaries set forth by DSHEA and the academy itself. The definition focuses on products containing dietary ingredients like vitamins, minerals, and herbs, ingested in specific forms to complement the diet. It explicitly separates them from conventional foods and pharmaceuticals. The professional's role is not to prescribe but to educate and empower clients to make informed decisions, safely and responsibly. Adherence to this scope of practice ensures client safety and professional credibility, underscoring NASM's commitment to evidence-based, responsible fitness and nutrition guidance. For more information on the regulations guiding dietary supplements, the FDA's website is a valuable resource. FDA Dietary Supplements Website

Frequently Asked Questions

NASM's definition is based on the legal framework established by the Dietary Supplement Health and Education Act (DSHEA) of 1994, which legally defines what a dietary supplement is.

No, it is outside the scope of practice for a NASM-certified professional to prescribe specific supplements or dosages. Their role is to provide general, evidence-based education.

According to the NASM-aligned DSHEA definition, a supplement can contain vitamins, minerals, herbs, botanicals, amino acids, or other dietary ingredients.

Supplements are intended to add to the diet, not to be represented as a conventional food or the sole item of a meal. They also have different labeling requirements.

No, the FDA does not approve dietary supplements before they are marketed. The responsibility for ensuring a product is safe and accurately labeled falls on the manufacturer.

A proprietary blend lists ingredients but not the specific amounts of each. NASM advises caution because the precise amount of each ingredient is not disclosed, making it hard to evaluate its efficacy or safety.

A NASM professional should refer a client to a registered dietitian, physician, or pharmacist for any questions regarding specific health conditions, medications, or specific supplement prescription needs.