NP 120: Microbiota-Gut-Brain Axis and The Diet-Mental Health Relationship

In the distant past, in ancient Greece, the father of medicine, Hippocrates, proclaimed that “All disease begins in the gut.” These wise words still ring true centuries later, and their significance deepens to include our understanding of how we think, feel, and experience.

You see, our gut is not just a mere food processor. It is home to trillions of microorganisms, collectively known as the microbiota. These tiny organisms communicate with one another and our bodies through intricate interactions, profoundly affecting our digestive, immune, and nervous systems.

But what does this have to do with our psychological well-being and mental health? Recent research has uncovered a fascinating link between the microbiota, the gut, and the brain, also known as the microbiota gut-brain axis (MGBA). This means that the state of our gut health can impact our mental health!

In this learning journey, we pose questions, present evidence, and impart knowledge. We do this with a vision that alludes to the infinite potential explanations for how our microbiota gut-brain axis (MGBA) and diet-mental health relationship (DMHR) interconnect.

So, whether you are a healthcare professional, a scientist, or simply someone interested in the fascinating world of the gut-brain connection, this course is for you. It’s a journey that promises to be exciting, enlightening, and even transformative!

This two-part course introduces the first evidence-based conceptual model linking the microbiota gut-brain axis to the diet-mental health relationship. This “Microbiota Gut-Brain Axis/Diet-Mental Health Relationship” is just one of the mechanisms within the emerging field of Nutritional Psychology.

Are you ready to take your first step into the intriguing world of the microbiota gut-brain axis and discover how it can shape your mental health and well-being?

May your “gut feeling” guide your well-being. Let’s get started.

NP 200 series in 2023.

This course is fully online, self-paced, and costs USD 350.00. CNP is approved by the American Psychological Association (APA) to sponsor Continuing Education (CE) for psychologists, as well as for LMFTs, LCSWs, LPCCs, and/or LEPs as required by the California Board of Behavioral Sciences and the Commission on Dietetic Registration (CDR) to provide Continuing Professional Education (CPE) credits for Licensed Dietitians and Dietetic Technicians Registered (RDs/DTRs). This course provides 10 CE and CPE Credits. CNP maintains responsibility for this program and its content.

Registering for NP 120 indicates that you have read and agreed to CNP’s Course Policy.

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NP 120 builds on the language, concepts, and methods presented in NP 110 and introduces one of the central mechanisms within nutritional psychology (NP) — the microbiota gut-brain axis (MGBA). Spanning evidence from the fields of neuroscience, physiology, nutrition, nutritional biochemistry, psychology, and psychiatry, this two-part course introduces the first evidence-based conceptual model linking the microbiota gut-brain axis to the diet-mental health relationship within nutritional psychology. This model is called the Microbiota Gut-Brain Axis-Diet Mental Health Relationship, also called the “MGBA-DMHR.” 

NP 120 is the second of three courses within CNP’s Introductory Certificate in Nutritional Psychology (NP). This introductory certificate is composed of NP 110, NP 120 (Part I & II), and NP 150 (available in 2024). Together, these courses form the theoretical basis underpinning the study of NP. 

NP 120 is composed of two parts — Part I and Part II. Part I is the prerequisite for NP 120. This course provides a solid introduction to the major components within the microbiota gut-brain axis (MGBA). It prepares learners to understand the physiological mechanisms through which the MGBA influences all aspects of the DMHR —including the psychological, behavioral, cognitive, sensory-perceptual, interoceptive, and psychosocial elements. 

NP 120 Part I systematically synthesizes some of the world’s research in MGBA and the DMHR, including its major components, tracing its historical evolution, and covering the primary approaches used within its research. We then delve into the gut microbiota and its specific role within the MGBA-DMHR, exploring its evolution, characteristics, and the factors contributing to its variation within and between individuals. The significance of the gastrointestinal barrier, its anatomy, and the influence of dietary intake on its integrity, permeability, and eubiotic and dysbiotic states are illustrated, along with its role within the MGBA-DMHR. Communication pathways and signaling molecules enabling top-down and bottom-up microbiota-gut-brain communication are presented. 

Part I prepares learners to begin understanding the mechanisms underpinning the MGBA and paves the way for the conceptual MGBA-DMHR model presented in NP 120 Part II.

For an overview of the course, download the course flyer.


  • • Psychologists and Mental Health Professionals
  • • Undergraduate, Graduate, and Post-Doctoral Students
  • • Dietitians, Nutritionists, Culinary Chefs, and Health Coaches
  • • Case Managers, Social Workers, School Counselors, Educators
  • • Physicians, Psychiatrists, Nurse Practitioners
  • • Substance Use Counselors
  • • Physician Assistants, Nurses
  • • Anyone interested in learning about nutritional psychology


  • Identify the seven major elements comprising the Microbiota Gut-Brain Axis (MGBA)
  • Identify three primary functions of the gut barrier
  • Define gut eubiosis, gut dysbiosis, and intestinal permeability
  • Discuss the impacts of fructose, glucose, artificial sweeteners, animal-based proteins, and fats on microbiota diversity and gut health
  • Explain how different dietary patterns, including the Mediterranean diet, Vegetarian/ Vegan diet, Western diet, and Keto diet, can impact the microbial ecosystem in the gut
  • Identify the five major gut-brain bidirectional communication pathways underpinning the pathophysiology of mental disorders
  • Explain the role of the microbiota-derived metabolites short-chain fatty acids (SCFAs) in the pathophysiology of anxiety and mood disorders
  • Identify the three primary MGBA-mediated pathways linking gut microbiota to subclinical experiences, including mood, emotions, and affect
  • Define the role of the microbiota gut-brain axis (MGBA) in the stress response and stress resilience
  • Describe the role of the microbiota gut-brain axis (MGBA) in both homeostatic and non-homeostatic (i.e., hedonic) regulation of dietary intake behavior
  • Identify six elements linking the microbiota gut-brain axis to Nutritional Psychology (NP) and the Diet-Mental Health Relationship

Instructor/Contributor Credentials

Ephi Lu holds a B.S. in Psychology from the University of Washington in Seattle, an M.S. in Psychology from the University of Illinois, and a Diploma in Comprehensive Nutrition. Ephi developed and taught the first college-level course in nutritional psychology for JFK University in 2008. She and Dr. Amanda Hull developed The Center for Nutritional Psychology in 2015 to serve as an online resource to consolidate the world’s research in the diet-mental health relationship and to continue the development of this area of study. Her vision is that all undergraduate and graduate students within the fields of psychology and nutrition have access to formal university-level education in the diet-mental health relationship and that an interdisciplinary connection between these disciplines is formalized going forward.

Shereen F. Behairy is a Clinical Pharmacist holding a Master’s degree in Pharmaceutical Sciences (Pharmacology & Toxicology), and her research has been published in high-impact scientific journals. She is currently a Ph.D. candidate in Neuropharmacology at Cairo University, Egypt. As she works toward her Ph.D., she’s conducting experimental studies on novel dietary interventions in treating brain disorders. She is a recent member of the Harvard Alumni Association (HAA) and recently completed the Clinical Scholars Research Training (CSRT) postgraduate program, where her capstone project investigated the potential link between dietary-induced gut dysfunction and hypertension progression in adult Egyptian patients. Her passion for neuroscience-inspired her to write her first book about the human brain and what goes beyond its normal physiological functions. Currently, she is pursuing her goal of becoming a professor because she firmly believes that good education has the power to enrich minds and the world. She is eager to contribute her relevant scientific background and collaborate with CNP’s diverse team of experts in various psychology and nutrition fields.

Youssef is developing his career as a physician-scientist and is a 5th-year medical student at Asyut University, Egypt. Youssef has passed the United States Medical Licensing Exam STEP1. His main area of interest and research is internal medicine and diseases related to neurocardiology. He has published numerous peer-reviewed studies and is a reviewer for PLOS medicine journal. Youssef has a nanodegree in data analysis from Udacity, and is interested in the application of R programming, data analysis, and machine learning to patient care and diagnostics. Youssef supports CNP with science-based writing, statistics, and curriculum development.

Ms. Doswell is pursuing her MS in Clinical Mental Health and Counseling at Adam’s State University. She has completed the original 7-course Certificate in Nutritional Psychology from JFK University and is a CNP curriculum contributor assisting in the development of the Interoceptive element of NP. She aims to incorporate her knowledge of the Diet-Mental Health Relationship into her graduate/clinical work, supporting those suffering from various eating disorders.

Course Administration

Joe Booth is CNP’s Online Education Developer. Joe brings a unique blend of professional experience in technology, education, and mental health. He received his Bachelor’s degree in Psychology from Sacramento State in 2005, and went on to run corporate Learning and Development programs for global software companies. Joe is currently the Executive Director of Class Five Mind, a substance abuse recovery platform that blends technology with mindfulness and holistic wellness.

Olga Baryshnikova is the Administrative Editor for NP 110, assisting with all aspects of content revision, course development, administrative implementation, and management. She has a background in industrial/organizational psychology and professional experience in education and marketing. She is also CNP’s Organizational Development Coordinator.

Continuing Education Planning Committee

Dr. Sam Scarnato

Dr. Kristine Lokken

Dr. Nicole Beurkens

Course Specifics

A: Yes, this course is taught fully online and can be completed at your own pace.

A: Yes, once NP 120 is available, you can begin at any time.

A: NP 120 is estimated to take 12-15 hours to complete, depending on your learning style and previous experience. If this information is new to you, it may take more time to complete.

A: NP 120 costs $350.00 USD. This price includes all course content, videos, download kits, knowledge checks, quizzes, the final exam, and your Certificate of Course Completion.

A: Yes! NP 120 is worth 12 CE credits for psychologists and other mental health professionals who receive CEs through the American Psychological Association (APA), and for LMFTs, LCSWs, LPCCs, and LEPs who receive CEs through the California Board of Behavioral Sciences. It is worth 12 CPEs for RDs and DTRs who receive credits through the Commission on Dietetic Registration. If your title is not listed here, please check with your licensing/certifying body to determine if you can earn CE/CPE credits by taking this course.

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CNP’s vision for the future of mental healthcare includes the role of diet and nutrients in supporting mental health. We are working to fill the void in our current mental healthcare model by consolidating research, creating methods, and developing curriculum that allows us to better understand and improve our Diet-Mental Health Relationship.

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