Functional Testing

Sometimes more information can help us see the bigger picture.

Functional testing can provide additional information about digestion, hormones, nutrient status, and other factors that may help inform your nutrition care.

But more testing isn't always better.

My approach is to use testing thoughtfully and selectively—choosing tests based on your symptoms, health history, and goals, then interpreting those results in the context of the whole you.

Ashley Tweddle preparing vegetables in a kitchen.
Ashley Tweddle preparing vegetables in a kitchen.

When might functional testing be helpful?

Functional testing isn't necessary for every client. In some situations, however, additional information may help us better understand patterns, identify areas that warrant further attention, or personalize your nutrition plan.

Testing may be considered when you're experiencing ongoing symptoms, when nutrition and lifestyle changes haven't provided enough answers, or when additional information could meaningfully change our approach.

Testing may be considered for concerns such as:

  • Persistent digestive symptoms

  • Bloating, constipation, diarrhea, or changes in bowel habits

  • Suspected SIBO

  • Food-related symptoms that remain difficult to understand

  • Menstrual or hormone-related concerns

  • Questions about nutrient status or possible deficiencies

  • Symptoms that haven't fully responded to initial nutrition interventions

Testing recommendations are always individualized. Having symptoms doesn’t automatically mean you need a functional test.

Functional Testing Options

Testing is selected based on your individual symptoms, health history, and goals. When appropriate, these tools can provide additional information to help guide your nutrition care.

GI-MAP

Comprehensive stool testing

GI-MAP provides information about gastrointestinal microorganisms and selected markers related to digestive health. Results are interpreted alongside your symptoms, health history, diet, and other relevant clinical information.

DUTCH Testing

Hormone and hormone-metabolite assessment

DUTCH testing provides information about selected reproductive hormones, cortisol patterns, and hormone metabolites. When appropriate, results can be considered alongside menstrual history, symptoms, nutrition, lifestyle, and conventional laboratory data.

SIBO Breath Testing

Assessment of intestinal gas patterns

Breath testing measures hydrogen and methane gases produced during the testing period and may be used when small intestinal bacterial overgrowth (SIBO) or intestinal methanogen overgrowth (IMO) is suspected.

Nutrient & Laboratory Testing

Targeted testing based on your individual needs

Depending on your health history, symptoms, and goals, additional laboratory testing may be considered to better understand nutrient status and other factors relevant to your nutrition care.

Testing is a tool—not the whole picture.

A test result is only one piece of information.

The goal isn't to collect as much data as possible or chase every result outside of a reference range. It's to ask the right questions, choose testing thoughtfully, and determine whether the results will actually change what we do next.

When we use functional testing, we'll interpret your results alongside your symptoms, health history, nutrition, lifestyle, and other relevant information to develop practical next steps.

The test doesn't determine your care—it helps inform it.

How Functional Testing Works

If we decide that functional testing could provide useful information for your care, I'll guide you through the process from choosing the appropriate test to understanding your results and determining what comes next.

01 — Decide if testing makes sense
We’ll discuss your symptoms, health history, goals, and what we hope to learn before deciding whether a test is appropriate.

02 — Complete your test
If we move forward, you'll receive everything you need to complete your test, including instructions for collecting and submitting your sample when applicable.

03 — Review your results
I'll review your results in the context of your symptoms, nutrition, health history, and other relevant information—not as isolated numbers on a page.

04 — Create your next steps
We'll use the information that is relevant to your care to guide personalized nutrition recommendations and, when appropriate, targeted supplement support.

Testing, Pricing, & Insurance

Functional testing can be incorporated into either insurance-based nutrition counseling or private coaching when appropriate. Functional laboratory testing and certain testing-related services are not billed to insurance through my practice, so these costs are paid separately.

The Test Itself

Functional laboratory tests are self-pay and are not billed to insurance through my practice. The cost varies depending on the test selected.

Before ordering, we'll discuss the recommended test, why it may be useful, and the expected testing cost so you can decide whether you'd like to move forward.

Review & Interpretation

Some functional tests require additional professional time outside of your nutrition appointments for detailed review and interpretation of results and development of individualized recommendations or supplement protocols.

When applicable, this work is provided as a self-pay service and is not billed to insurance. Any additional fees will be discussed with you before testing is ordered.

No surprise costs.

Before moving forward with functional testing, we'll discuss what we're testing, why we're testing it, the expected costs, and how the results will be incorporated into your nutrition care.

Wondering whether functional testing makes sense for you?

Functional testing isn't necessary for everyone. If you're curious whether testing could be useful as part of your nutrition care, we can discuss your symptoms, health history, and goals and determine the most appropriate next step together.