I’m Gretchen Zimmermann RD, CDCES, CLT

Your Thyroid & Digestive Health Dietitian


Helping You to Heal Your Gut and Take Control of Your Thyroid Health

Nutrition Therapy

Research suggests there is a connection between gut health and autoimmune conditions. If you have IBS or autoimmune conditions like Hashimoto’s Thyroiditis and IBD, learn what your personal food intolerances are so you can heal your gut and find the path towards feeling your best.

Meal Planning

Planning meals is key to your success when you have Hashimoto’s or digestive issues. Check out my gluten-free, low FODMAP and anti-inflammatory meal plans

low-FODMAP for IBS

The low-FODMAP diet is the preferred dietary treatment for IBS with nearly 85% of people reporting an improvement of symptoms.

LEAP/MRT for IBS, IBD, Hashimoto's

The MRT/LEAP plan is most helpful for uncovering foods that may be causing inflammation and symptoms like brain fog, fatigue, bloating, diarrhea, abdominal pain, migraines. Most clients experience improvement in their symptoms within 10-14 days.

Meal Plans

Interested in trying a low-FODMAP or gluten-free, anti-inflammatory meal plan for 3 days? A 3-day FREE trial is available for all plans! After that, plans start at $9/month.

Recipe & Wellness Blog

Enjoy some of my favorite AIP, low-FODMAP, gluten-free and dairy free recipes, wellness and digestive health tips.

How do I get started?

(Please note, I am currently not taking new clients.)

1. Take the LEAP/MRT symptom survey quiz. This will help us decide on the best nutrition therapy approach for you. Once you complete this, I will contact you to schedule a call.

2. If you prefer to talk first, schedule a complimentary discovery session.

3. During our discovery session, we discuss what approach may be best for you, based on your medical history, diagnosis and symptoms.

1. Do you take health insurance?

Unfortunately, health insurance does not cover many registered dietitian provided services. I do not accept insurance and all of my services are self-pay.  I take cash, credit card and HSA.I can provide a superbill to submit to your insurance, upon request but there is no guarantee of coverage.  I do offer payment plans for my services so please let me know if this would be a better option for you!

2. I have GI symptoms but no diagnosis yet - can we still work together?

Because other potentially serious conditions cause similar symptoms, you should discuss your GI concerns with your primary care physician or gastroenterologist first. A diagnosis will determine the appropriate medical treatment plan and nutrition therapy for you.

3. How do I know if I am good candidate for LEAP/MRT or low-FODMAP nutrition therapy?

For both LEAP/MRT and low FODMAP, it is important that you do not self diagnose and have discussed your symptoms with your MD to rule out celiac disease, IBD and other potential serious GI and gynecological conditions like bowel cancer and endometriosis.

Also, if you have an eating disorder or history of an eating disorder, this type of nutrition therapy may not be right for you.

If you have discussed with your MD and have IBS symptoms, the low FODMAP diet may help to alleviate your symptoms. If you experience other symptoms such as headaches, fatigue, or skin conditions, LEAP/MRT may be a better option. 

It is important to choose the least restrictive approach possible. Complete the food symptom survey and schedule a consult to determine which nutrition therapy approach would be best for you!


4. What is leaky gut and how is it connected to food sensitivities?

Leaky gut, also known as intestinal permeability, is damage to the lining of the intestinal tract making it more permeable to substances that should not cross the lining.  When these substances such as undigested food particles, bacteria, and toxins cross the lining into the bloodstream, your immune system recognizes them as foreign substances and creates an inflammatory response. This is when you might experience symptoms like brain fog, fatigue, digestive problems, bloating, headaches, and pain.

Causes of leaky gut may include SIBO, autoimmune conditions like celiac disease, and undiagnosed food sensitivities.

Food sensitivities are the main cause of symptoms related to leaky gut.  They are often dose-dependent and have delayed reactions, making them difficult to pinpoint. The MRT test helps by quantifying the degree of the inflammatory response to a wide range of foods and chemicals, identifying your “reactive” foods.

Read more here about leaky gut and food sensitivities.

5. What is the link between food sensitivities and inflammation?

Food sensitivities are non-allergic, non-celiac reactions, leading to the release of pro-inflammatory mediators that cause symptoms like headaches, brain fog, digestive issues, etc.

Good health starts in the gut.  Many conditions, like Hashimoto’s benefit from restoring gut health

Click here for a more in-depth look at how this process works. 

Nutrition Therapy for Gut and Thyroid Health

90-Day Gut Healing for IBS Program

If you have been diagnosed with IBS and  experience symptoms like lower abdominal pain, bloating, excess gas, distention, diarrhea, and constipation, the low FODMAP eating plan may help to ease your symptoms. Learn more about low FODMAP.

More Details


Initial comprehensive nutrition assessment (60 minutes)

Four follow-up sessions (30 minutes)

Personalized nutrition plan with guidance for how to implement the low FODMAP diet through all phases.

Help with meal planning, weekly email support, and accountability.

Schedule a complimentary call to find out if this is the right plan for you.

90-Day Hashimoto’s Healing Program

There is a strong connection between gut health and Hashimoto’s. If you’re looking for a personalized, tailored plan based on your individual food sensitivities, LEAP/MRT may be right for you. The MRT blood test takes the guesswork out of general elimination diets and will identify what foods may be causing inflammation and triggering your symptoms.  Learn more about LEAP/MRT.

More Details

For those of us with Hashimoto’s, identifying triggering foods, reducing inflammation and healing the gut is often the first, most important step towards healing. In this program we take a holistic approach and focus on other lifestyle factors like stress and sleep to help you heal and feel your best. Not interested in MRT/LEAP at this time? Ask me about AIP. I’m happy to customize a package for you.


Initial Pre-LEAP assessment (60 minutes)

Post-MRT session to discuss results/implement personalized LEAP plan (60 minutes)

Five follow-up sessions (30 minutes)

MRT blood test for 170 common foods and food chemicals

60-page resource guide with recipes, tips

Help with meal planning, weekly email support, and accountability.

About Me

Hello! My name is Gretchen and I am the founder of HappyGoHealthyRD, LLC.  I am a registered dietitian, certified diabetes educator, certified LEAP therapist, and a Monash trained low-FODMAP dietitian.

Recently diagnosed with Hashimoto’s thyroiditis,  I understand what it feels like to make significant changes to diet and lifestyle. After years of working on my own relationship with food and my body and getting to a place where I could eat all my favorite foods without guilt, I now make specific choices to support a healthy gut and immune system so I can feel my best

I’d like to help you learn how to do the same!

Originally from New York, by way of San Francisco, I now live in Colorado in a 100-year-old log home. My happiness can be found running the beautiful trails here in CO.

Besides running, I am also a big fan of my two cats {Cookie and Fluffhead}, motorcycle adventures, and my non-running, Phish-loving partner in all the fun things in life, my husband, Joe!


In happiness and health, Gretchen


Gretchen was a joy to work with…easygoing, helpful and knowledgable. She was a good listener and tailored the sessions to my biggest needs and goals. She was great with follow up and always gently checked in to see how things were going between sessions. I would highly recommend her!

“For decades, I have struggled with weight/body image and have tried every diet out there. I didn’t eat carbs, I didn’t eat sweets, I didn’t eat this, that and the other thing. I took dieting to an unhealthy extreme. After working with Gretchen on mindful eating, it all clicked. At 35ish years old, a light bulb went off. It all made sense.

I now eat anything I want for the most part. I eat until I am satisfied. I eat when I am hungry. I have learned to not let my emotions (happy, stressed, bored, sad) dictate what and when I eat.”

“Working with Gretchen on mindful eating made me look at how I am approaching food. “Pause” is a such a powerful  thought and I will use it…everyday!

You put words to feelings that I’ve struggled with for so long, but I am starting to change those habits and beginning to listen more to my body.

In charge instead of in control. Love it. So true.”

Banana Oat Pancakes

These flourless banana oat pancakes, made with just four ingredients, are hearty, satisfying and delicious! They’re made with ripe bananas, eggs, peanut butter and oats and couldn’t be easier to make! Enjoy them topped with fresh berries, coconut yogurt, maple syrup or honey. These pancakes are flourless, vegan, gluten and dairy-free.

Flourless Peanut Butter Oat Breakfast Cookies

These flourless peanut butter oat breakfast cookies, made with just three ingredients, are soft, chewy, lightly sweet and easy to make! They’re made with peanut butter, oats, and mashed banana, making them an ideal choice for a quick breakfast option or a wholesome, healthy snack. These cookies are vegan, gluten and dairy-free!

Spiced Chickpea Soup

This spiced chickpea soup is made with deliciously warming spices like cumin, ginger, smoked paprika, and coriander.  It can be made in a big batch and freezes well. Best of all, this recipe is gluten and dairy-free!

Lemon Ginger Smoothie Bowl

This immune boosting lemon ginger smoothie bowl has bright and fresh flavors featuring anti-inflammatory and immune-supporting ingredients.

Baked Coconut Cardamom Apples

These baked apples with cardamom and coconut make a delicious and healthy dessert or snack. Enjoy with coconut yogurt or top with non-dairy ice cream!

Does a Gluten-Free Diet Improve Thyroid Health?

For people with Hashimoto’s it is often recommended to follow a gluten-free diet but does the research support this?

Frozen Chocolate Yogurt Bark

This frozen chocolate coconut yogurt bark is easy to make and is both dairy and gluten-free. Makes a perfect snack or healthy dessert.

Mindful Eating: In Charge vs. In Control

Embrace Mindful Eating and find food freedom! The new year is finally here, and whether you're someone who makes resolutions or not, there's a good chance that you may be thinking about how to improve your health, how to lose weight, exercise more, quit smoking, etc....

Spiced Stuffed Acorn Squash

This stuffed acorn squash features black rice, also known as forbidden rice, which gives a slightly sweet, nutty flavor to the dish and is packed with good-for-nutrients not found in other rice varietals.

Warm Quinoa Butternut Squash Salad

This warm quinoa and butternut squash salad is a wonderful combination of different textures and flavors – it’s warm and comforting. Serve as an entrée or side dish.

Don’t Wait Any Longer. Take Charge of Your GI and Thyroid Health Today!