“Let food be thy medicine and medicine be thy food”  ~Hippocrates 

Welcome to Custom Fit Nutrition. We are a team of dietitians and Board Certified Holistic Nutrition Consultants trained at Bauman College, and we believe that the key to health is simple: eat real food. It’s not about restriction, crazy juice cleanses, or taking a daily handful of supplements while ignoring your food quality. Let’s face it, diets just don’t work on a long-term basis for most people. It’s about building a foundation of healthy eating practices and finding foods that fit into your lifestyle that help you to feel and look your best. 

There is so much nutrition and health information circulating around that dictates what to do and eat to be “healthy.” There is always a new diet trending, and a new study that claims to be the answer to weight loss. Sifting through the wealth of nutritional information can be overwhelming, frustrating, and confusing. The truth is, there is not a one size fits all approach to good health. Every individual has different needs and a different emotional connection to food. At Custom Fit, our goal is to find the path that is right for you. We use the most up to date nutritional practices and combine it with lifestyle recommendations and the option of personal training to help you be as healthy as possible.

We work one on one with you to develop a program that is customized specifically for your unique needs and goals. We collaborate with your personal trainers (if you choose to go that route) to develop nutrition plans that are in conjunction with your fitness goals. We take into account every individuals' unique tastes/preferences, allergies/sensitivities, family history, health complications, cooking experience, finances, and perhaps most importantly the time they have available to dedicate to cooking. Whether you are looking to lose weight, eat for fertility, manage an existing health condition, gain muscle, or simply be healthy, we can work together to set goals and find solutions to achieving them.

Nutrition Services & Pricing

One Hour Q&A with a Nutritionist - $115

One 60-minute session is ideal for someone who would like to meet with a nutritionist to ask questions and gain more understanding of optimal nutrition. This can be done in person or over the phone and will include relevant material to help you achieve your goals.

Foundations of Nutrition - $A.Q.

We offer a customized nutrition program based on each clients’ individual needs. This can include: 

  • As needed one-on-one sessions with a nutritionist in-person at our studio or via FaceTime or Skype.

  • Regular email check-ins and support.

  • Personalized Nutrition & Health Plan with caloric and macronutrient recommendations, foods to include, foods to avoid, lifestyle, and supplement recommendations.

  • Meal planning support. Meal planning varies depending on your goals and lifestyle. We offer a range of meal planning options from very flexible to more prescriptive.

  • Food journal analysis and tracking guidance.

  • Guidance in choosing restaurants, healthy take-out, meal kits, and/or meal delivery.

  • Recommended and relevant resources specific to your needs.

On-Going Nutrition Services 

Once you complete the Foundations of Nutrition Program, most people opt for on-going nutritional support.  Please inquire for details.

For questions or additional information about nutrition services please contact Marissa at:

Dietitians & Nutritionists


Marissa Mather

Nutritionist / Owner

Food and cooking has been a lifelong passion of mine. Growing up, my mother was a dietitian, so we always had an emphasis on eating healthy and balanced meals. My Greek background allowed me to learn a lot about the Mediterranean diet as well as the importance of enjoying meals with family and friends. Born and raised in the Bay Area, I love learning and being immersed in the inspiring and innovative food scene that we are world famous for. Before studying to become a nutritionist I worked in the restaurant industry for 10 years, so my passion for food is not only focused on health, but being delicious as well! I love learning, researching, and testing new recipes that utilize local and seasonal ingredients, are easy to make, and most importantly taste great. I truly believe that healthy, nourishing food can be enjoyable and designed to fit into everyone’s lifestyle, regardless of time, finances or skill.

Certifications & Education

Bauman College - Certified Nutritionist

California State University Chico - Bachelor of Arts (International Relations)




Tarah Venn

Registered Dietician

My background in nutrition started in the sports world. I grew up with an athlete as a father and watching him nourish and train his body for performance taught me the power of nutrition on performance outcomes. When I went to college, I discovered my passion for human biology and disease prevention through behavior change. This lead me to dive deeper into science and medicine, pursue an education in nutrition and become a registered dietitian. Through my experiences working in clinical research and private practice I continue to be amazed at what the human body and mind are capable of. I love working with people to discover new ways to improve their health, eliminate barriers and enhance their overall wellbeing and sense of empowerment. I sincerely believe that we can all unveil a brighter, happier self with the power of nutrition and delicious food!

Certifications & Education

San Francisco State University - Bachelor of Science (Dietetics)

Cornell University - Dietetic Internship

Commission on Dietetic Registration, Academy of Nutrition and Dietetics - Registered Dietitian




Brooke Wilson

Nutritionist / Natural Chef

Originally from Louisville Kentucky, I grew up in the land of horse racing, bourbon, and southern food. I have since been on my own journey towards optimal health. I made my way to the Bay Area many years ago to learn about holistic nutrition and study food's miraculous ability to support health and to heal. Through my work as a nutritionist I most enjoy working with people to help them achieve their goals and support them as they start to see how changing the way they eat can profoundly impact the way their body feels and functions, their energy levels, their moods, and their ability to focus/concentrate. My passion is making food both healthy and delicious so I’m forever experimenting in the kitchen. I’m thrilled to be a part of the Custom Fit team!

Certifications & Education

Bauman College - Certified Nutritionist

Bauman College - Natural Chef

University of North Carolina - Masters of Social Work

University of North Carolina - Bachelor of Arts (Psychology)