Yes, and in some cases this is strongly recommended.
There are generally three scenarios.
In the first scenario, a client has no serious complaints, and all issues identified through lab results can be addressed through nutrition, lifestyle changes, and supplementation. For example, correcting iron deficiency, other nutrient deficiencies, insulin resistance, or weight-related concerns often does not require direct medical intervention. This also includes cases where a diagnosis has already been established and remains stable, such as chronic gastritis, bile flow disorders, rosacea, dermatitis, chronic thyroid conditions, acne, and similar issues.
In the second scenario, a client has recently received a diagnosis and treatment plan from a physician and comes to me to complement that work. I focus on areas that doctors often have limited time to address, such as tailored dietary adjustments and more detailed monitoring of blood markers, followed by a personalized supplement strategy. In many cases, I ask clients to coordinate my recommendations with their treating physician. This kind of collaboration benefits the client most.
In the third scenario, after reviewing the intake questionnaire and diet, I determine that the issue falls outside my scope of practice. In this case, I refer the client to the appropriate medical specialist and suggest which tests to complete. After that, we either continue working independently, as in the first scenario, or in collaboration with the physician, as in the second.