Nutrition Behavior Change

How to Help Clients Change Their Eating Habits

Brad Dieter
Brad Dieter
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One of the most important things regarding “healthy eating” is to understand that what we eat is tied into our habits.

A habit is defined as: “a settled or regular tendency or practice, especially one that is hard to give up.”

Think about it for a moment and reflect on what you eat. Do most days consist of very similar food choices or patterns of behavior surrounding food? For most of us, including most of our clients, the answer is a resounding yes. As such, making strides in clients’ nutrition revolves a lot around helping them change their habits.

There are several ways to help clients change their habits, but one of the most helpful ways to do so is mirror the self-determination theory framework and focus on the client’s autonomy, relatedness, and competence. This article will explore each of these three areas and provide direction and insights on how to address them with regard to changing a client’s habits around food.


Autonomy is essentially the control and ownership a client feels about their decisions. Generally speaking, the more a client feels in control and “owns” their decisions, the more likely they are to become a habit. For example, if a trainer or coach were to live with a client for a week and make all their food choices for them, is it likely that the client would “own” the food decisions being made? Not likely.

Conversely, how much of the food decisions would a client own if a coach were to help a client navigate their days and provide options for food and allow the client to choose what they ate and when they ate, with some guidance? Much more likely.

There are several ways to promote and build autonomy with a client around their nutrition habits.

Related: Intuitive Eating Principles Explained

1. Build trust and rapport with the client: 

Clients are more likely to take ownership of their decisions if they feel like there is mutual respect and an established relationship and culture of honesty between the client and the coach.

2. Allow for Mistakes

Part of building autonomy is allowing for imperfect decisions and choices. Each choice is a learning opportunity and mistakes allow a client to own ALL decisions, not just the best ones.

3. Structure first, freedom second

While a large part of autonomy is based on allowing clients to make choices, the job of the coach is to provide structure around those choices. When a client is first starting, provide them a narrow selection of choices, all of which are considered “good choices.” Once a pattern is set and a structure is built, build in more freedom.


Relatedness, often called connection, is how related or connected the client feels to the task at hand. Is the client fully engaged and do they understand why their nutrition habits are important to their end goal? Or do they not understand the importance and have no relatedness to it?

There are several ways to make one’s nutrition habits more related to the client. Here are a few of the most effective ways.

1. Tie the client’s habits to their wants and needs

For example, if a client wants to lose 10% of their body weight to improve their cardiometabolic markers, help them understand exactly how their habits relate to that. Are their current habits putting them closer to that goal or further away? What can they do to put them closer?

2. Surround them in environments that reinforce their habits

We value, model, and reflect what we see in our environment. Can you help a client change their food environment such that their habits become more related? Perhaps you can help them change their home food environment or where they grocery shop or their route home from work (do they drive by fast food places or by health food stores?).

3. Connect with your client and model your habits

People’s habits mirror those around them. One way to help your client make their habits more related is to model the behaviors in yourself!


Competence is defined as “the ability to do something successfully or efficiently,” and it is one of the most critical aspects of changing one’s eating habits.

Building competence around habit change can be much more simple than most people think. There are a few main areas in which you can focus on building competence with your clients.

1. Education about nutritional needs

Providing a basic understanding about caloric balance, macro- and micronutrient requirements, and nutrition facts about food can help provide a foundation for clients.

This foundational education can be used for them to inform themselves about how their current habits are shaping their nutritional intake and what type of changes they might need to make to reach their new habits.

2. Skill Competency

Changing nutrition habits requires more than just understanding basic nutrition science concepts; it also requires the development of real-world skills. These skills involve food preparation (e.g. cooking), grocery shopping, and navigating restaurant menus.

It's always important to brush up on your nutritional knowledge as a fitness professional as well. Regularly enrolling in CEU courses is a must! 

 3. Habit setting competence

There are more effective ways to establish habits than just “do things and hope for the best.”

Start small

It is easier to change small habits and build momentum than try and tackle the biggest, most difficult one first. For example, if you are trying to improve your overall diet and you absolutely love your daily 3 P.M. soda but are not really that invested in your daily breakfast of a fast-food breakfast sandwich, keep the soda but change your breakfast routine to an at-home breakfast.

Set goals with your habit in small chunks:

When you finally commit to kicking the 3 P.M. soda, you don’t need to start with the goal of, “I am not drinking a soda for the next 90 days.” Instead, start with a more achievable, tractable goal, such as, “I will only have my soda Monday, Wednesday, and Friday, this week.” Then build from there.

Provide positive feedback:

Humans thrive on positive reinforcement, even if it is self-given. Provide positive feedback to your client and have them provide it to themselves. This can look like a reward for establishing a new habit or removing an old one.

The wrap up 

Many of our nutritional lives are steeped in habits. Central to making improvements in one’s nutrition is changing one’s eating habits. One of the best ways to help clients change their patterns is to help them gain autonomy through building relationships, providing structure, and allowing clients to make mistakes and learn.

It is also critical to help them understand how their habits relate to their goals and what matters to them in their lives. Building relatedness and tying that to their habits will help instill them. Lastly, competence is critical to your clients being able to implement the desired habit change. Competence can be built through education, teaching them skills that can help them instantiate their habits, and also teaching your clients how best to implement habits in their daily lives.

If you're interested in learning more ways to help clients change lifelong habits and strategies to help them break dietary patterns, become an NASM Certified Nutrition Coach.

The Author

Brad Dieter

Brad Dieter

Brad is a trained Exercise Physiologist, Molecular Biologist, and Biostatistician. He received his B.A. from Washington State University and a Masters of Science in Biomechanics at the University of Idaho, and completed his PhD at the University of Idaho. He completed his post-doctoral fellowship in translational science at Providence Medical Research Center, Providence Sacred Heart Medical Center and Children’s Hospital where he studied how metabolism and inflammation regulate molecular mechanisms disease and was involved in discovering novel therapeutics for diabetic complications. Currently, Dr. Dieter is the Chief Scientific Advisor at Outplay Inc and Harness Biotechnologies, is co-owner of Macros Inc and is active in health technology and biotechnology. In addition, he is passionate about scientific outreach and educating the public through his role on Scientific Advisory Boards and regular writing on health, nutrition, and supplementation. Want to learn more in Brad's areas of expertise? Check out his NASM product recommendations.


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