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The Benefits of Functional Lab Testing - Empowering Your Path to Wellness

When you know you don't feel right, but your conventional lab tests are "normal," it's time to dig a little bit deeper!

Image of healthy digestive tract without leaky gut

Have you ever had a health problem and after an evaluation and conventional testing from your healthcare provider, you're told that there is nothing wrong? But the real problem is that you still have symptoms, and your body is telling you that there IS something wrong!

You're not alone. While conventional lab and other diagnostic testing can be very helpful in determining the root cause of symptoms, sometimes a basic lab draw doesn't provide all the answers. First and foremost, if you have a health concern you should always consult your physician first. If your diagnostic tests show no clear health problem based on your physician's analysis, then functional lab testing may be a useful tool to better understand the root cause of your symptoms.

What is Functional Lab Testing?

Functional lab testing is a form of testing that focuses on identifying imbalances in the body's physiological functions. Unlike conventional lab tests that merely measure markers within standard ranges, functional lab testing seeks to discover the root causes of health issues by evaluating different biomarkers to better understand how different systems in the body interact.

An example of this difference in testing can be seen in the evaluation of vitamin B12 status. A conventional lab draw may include a serum vitamin B12 level which provides information about how much vitamin B12 is circulating in your blood. However, a functional lab test may measure a biomarker called methylmalonic acid (MMA) in urine or blood, which is a more accurate biomarker for identifying how much vitamin B12 is getting into the cells (where energy production occurs) versus knowing how much is circulating in the bloodstream.

Functional lab tests assess many different biomarkers such as vitamins, minerals, essential fatty acids, organic acids, hormones, gut microbes, digestive function markers, genetic markers, and other factors. Many tests may be conducted by using an at-home test kit where you can collect your sample at home (urine, blood spot, stool, or saliva) and mail the sample to the laboratory for analysis. Some functional lab tests may require a blood draw by a phlebotomist at a lab draw facility. Your healthcare practitioner will interpret the lab results and provide recommendations during your follow-up consultation.

Different Types of Functional Lab Tests

There are a wide variety of functional lab tests available. A qualified healthcare professional who has had advanced training in functional nutrition therapy or functional medicine therapy is the best resource to help you decide which test is most appropriate for your health needs. Working with a functional healthcare professional who has access to professional grade testing and certified laboratories is advised. Here is a list of some of the most useful functional lab tests:

Digestive and Gut Function Analysis

  • Functional Stool Testing

A comprehensive stool analysis assesses the health of your gastrointestinal system, gut microbial balance, and digestion. It can identify imbalances in gut bacteria, detect the presence of parasites or harmful pathogens, and evaluate digestive enzyme production. The test may include other digestive health biomarkers, such as one for increased intestinal permeability (i.e., leaky gut syndrome).

Functional stool testing is beneficial for those with digestive complaints (e.g., diarrhea, constipation, gas, bloating), IBS, IBD, food intolerances, autoimmune conditions, brain fog, skin conditions (e.g., acne or psoriasis), mood imbalances, diabetes, or weight management issues.

  • SIBO Breath Testing

A SIBO breath test measures fermented gases produced in your gut and can help identify conditions like small intestinal bacterial overgrowth (SIBO), intestinal methanogenic overgrowth (IMO), and excess hydrogen sulfide. A breath test that measures three gases (hydrogen, methane, and hydrogen sulfide) versus the typical two gases (hydrogen and methane) will provide more information that will assist in developing an effective digestive wellness plan.

A SIBO breath test is beneficial for those suffering from chronic gas, bloating, constipation, or diarrhea. It is frequently combined with a functional stool test for a comprehensive evaluation of digestive function and imbalances.

  • Food Sensitivity Testing

Food sensitivity testing helps identify specific foods that may trigger adverse reactions in your body. Unlike allergies, which cause an immediate response, sensitivities can lead to delayed symptoms like bloating, headaches, or joint pain. By identifying trigger foods, you can make informed dietary changes to improve your health.

Food sensitivities are frequently caused by imbalances in the gut and may not be permanent issues. Working with a Registered Dietitian Nutritionist can help you prevent nutrient deficiencies while eliminating certain foods, guide you through a digestive health improvement process, and assist with a reintroduction trial of sensitive foods after the gut has healed. Many people are able to tolerate foods to which they were previously sensitive after implementing a digestive wellness plan.

Female Health

  • Hormone Testing

Hormones play a vital role in regulating various bodily functions, including metabolism, reproduction, mood, and stress response. Hormone testing examines levels of hormones such as estrogen, progesterone, testosterone, cortisol, melatonin, and thyroid hormones.

Hormone testing can help identify hormonal imbalances, which can contribute to issues like fatigue, weight gain, mood swings, premenstrual symptoms (PMS), menopausal symptoms, and reproductive problems.

Nutritional Health

  • Micronutrient Testing

A micronutrient test may evaluate anywhere from 30 to 100 biomarkers and assess the body's functional need for antioxidants, vitamins, minerals, essential fatty acids, amino acids, digestive support, and other select nutrients. What makes this test different than a conventional blood test is that it measures the functional level and capability of micronutrients in the body which accounts for a person’s biochemical individuality.

Micronutrient testing may be beneficial for those who have fatigue, poor concentration, mood disorders, diabetes, heart health issues, weight management difficulty, or desire sports performance optimization. Anyone who is interested in their nutritional status can benefit from the information provided in this test, including those who eat a limited diet due to food avoidances or those who eat a diet that lacks fresh fruits and vegetables and contains processed or fast foods.

  • Organic Acids Test (OAT)

An organic acids test provides an analysis of key nutritional biomarkers. It assesses the functional need for antioxidants, B-vitamins, minerals, digestive support, and amino acids. It also addresses cellular energy and mitochondrial metabolites, neurotransmitter metabolites, and toxin and detoxification markers.

Organic acid testing may be beneficial for those who experience fatigue, chronic stress, inflammatory issues (e.g., achiness, joint problems, brain fog), mood disorders, diabetes, heart health issues, weight management difficulty, or desire sports performance optimization. Similarly to the micronutrient testing, the OAT may be helpful to anyone who is interested in their body's nutritional status due to lack of balanced nutritional intake in their diet.

General Health

  • Environmental Toxin Exposure

We are exposed to a wide variety of toxins from the environment and common household products. Environmental toxins include manufactured or naturally occurring substances that can cause temporary or chronic toxic overload when absorbed, inhaled, or ingested. These may include heavy metals (e.g., lead in water), pesticides, petroleum by-products, and other chemicals. Even plastic components from water bottles or food containers can leach into our food and water that we consume. High exposure to toxins can have negative health effects as it can affect multiple body systems.

An environmental toxin test may be beneficial for those who know they have had exposure to toxins or have chronic inflammatory conditions, resistance to weight loss, or other signs of toxic burden.

  • Genetic Testing

A comprehensive genetic test may evaluate over 100 genes that influence metabolism, inflammation, detoxification, performance, weight, hormones, cognition, and response to diet and supplements. This information may provide insights into nutrition, fitness, illness prevention, and weight management recommendations.

Genetic testing is beneficial for those who want to understand how their genetics can impact their health so that they can make optimal decisions to potentially reduce risk of illness, or maintain or improve health. It can be helpful in optimizing a personalized plan for nutrition, exercise, weight management, and wellness.

Benefits of Functional Lab Testing

Functional lab testing should not replace conventional lab testing and regular visits with your doctor. Rather it can be a complementary source of information that may enhance your path to feeling better. Here are the primary benefits of including functional lab testing in your wellness journey:

  • Personalized Approach: One of the most significant advantages of functional lab testing is its personalized nature. By examining individual biomarkers and physiological processes, practitioners can tailor wellness plans to address your unique health needs. This approach increases the likelihood of successful outcomes compared to generic, one-size-fits-all plans.

  • Identifying Root Causes: Conventional healthcare often treats symptoms rather than the root causes of health problems. Functional lab testing digs deeper to identify the underlying imbalances contributing towards symptoms. By addressing these root causes, you can experience more sustainable improvements in your health.

  • Focus on Prevention: Functional lab testing can often detect imbalances long before they manifest as noticeable symptoms or conditions. This early detection allows for proactive lifestyle interventions to prevent potential health issues from escalating.

  • Comprehensive Health Assessment: Instead of isolated snapshots, functional lab testing provides a comprehensive overview of your body's systems and how they interact. This broad perspective allows healthcare practitioners to better understand the complexity of your health and devise holistic wellness plans.

  • Monitoring Health Improvement: Functional lab testing is not a one-time affair. It allows for periodic monitoring of your health and the effectiveness of your wellness plan over time. Adjustments can be made to optimize your progress and maintain your overall wellbeing.

  • Improved Gut Health Analysis: The gut plays a crucial role in overall health, and functional lab testing can provide valuable insights into the gut microbiome, digestive function, and intestinal health. A healthy gut is linked to improved immune function, mental health, and more.

  • Support for Chronic Conditions: For individuals dealing with chronic health conditions, functional lab testing can offer additional guidance. It helps reveal imbalances that may exacerbate chronic issues and opens new avenues for targeted nutrition and lifestyle interventions.

Bottom Line

Functional lab testing offers a powerful and insightful approach to understanding and optimizing your health. By exploring the root causes of imbalances, it empowers healthcare practitioners to provide personalized and effective wellness plans.

If you seek a more holistic and individualized approach to your wellbeing, consider discussing the benefits of functional lab testing with a qualified Registered Dietitian Nutritionist who has experience in functional lab work. You may also book an Introductory Call with Kirkman Nutrition to see if our programs/services can help you.


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