Research on Elimination Diets and Healing | Functional Medicine Finder

Q: What is the main goal of functional medicine?

The main goal of functional medicine is to identify and address the root causes of chronic disease, rather than just managing symptoms. It takes a patient-centered approach, considering each person's unique genetic, environmental, and lifestyle factors to create personalized treatment plans. This holistic view aims to restore balance and promote long-term health, as demonstrated by studies showing functional medicine's association with improvements in health-related quality of life [https://news

Q: How was health-related quality of life measured in the Cleveland Clinic study?

Health-related quality of life in the Cleveland Clinic study was measured using the Patient-Reported Outcome Measurement Information System (PROMIS®) questionnaire. This NIH-validated tool assesses various aspects of global physical and mental health, including fatigue, physical function, pain, gastrointestinal issues, and emotional well-being. By tracking PROMIS scores, researchers could quantify improvements in patients' daily lives, with 31% of functional medicine patients showing a clinicall

Q: What is a 'clinically meaningful change' in PROMIS scores?

A "clinically meaningful change" on PROMIS Global Health T-score scales is defined as an improvement of 5 or more points. This threshold indicates a noticeable and significant effect on a patient's daily life, meaning the change is substantial enough to be felt by the individual. In the Cleveland Clinic study, 31% of functional medicine patients achieved this clinically meaningful improvement in their PROMIS global physical health scores at 6 months [https://jamanetwork.com/journals/jamanetworko

Q: Are shared medical appointments more effective than individual appointments in functional medicine?

Yes, shared medical appointments (SMAs) have been found to deliver improved outcomes compared to individual appointments in functional medicine. A Cleveland Clinic study found that patients in SMAs exhibited greater improvements in both PROMIS Global Physical Health T-scores (mean difference 1.18) and PROMIS Global Mental Health T-scores (mean difference 1.78) at 3 months. SMAs were also less costly to deliver and resulted in greater weight loss (mean difference -1.4 kg) [https://pubmed.ncbi.nlm

Q: What chronic conditions does functional medicine address?

Functional medicine aims to address the root causes of a wide range of chronic conditions. While the Cleveland Clinic studies focused on general chronic conditions and health-related quality of life, the model's personalized approach allows it to be applied to various issues. For example, the Functioning For Life® SMA program addresses "various chronic conditions through the use of food as medicine" [https://newsroom.clevelandclinic.org/2021/04/13/cleveland-clinic-study-finds-functional-medicine

Last updated: April 2026

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Quick Answer

Functional medicine focuses on addressing the root causes of chronic disease.
A Cleveland Clinic study found 31% of functional medicine patients improved their physical health by 5 points or more at 6 months, a clinically meaningful change.
Shared medical appointments for functional medicine deliver better outcomes and are less costly than individual appointments.
Patients in shared medical appointments (SMAs) experienced greater weight loss, with a mean difference of -1.4 kg, compared to patients in individual appointments.

Functional medicine offers a patient-centered approach to healthcare, aiming to uncover and treat the underlying causes of chronic diseases instead of just managing symptoms. Research from the Cleveland Clinic shows this model is associated with meaningful improvements in health-related quality of life. For example, a two-year study found that 31% of patients in the Center for Functional Medicine improved their PROMIS global physical health scores by 5 points or more within six months, which is considered a significant change in daily life [https://newsroom.clevelandclinic.org/2019/10/25/cleveland-clinic-study-finds-functional-medicine-model-is-associated-with-improvements-in-health-related-quality-of-life]. This approach often involves personalized lifestyle interventions, including nutrition and diet modifications, which are central to addressing root causes. Furthermore, functional medicine care delivered through shared medical appointments (SMAs) has been shown to improve outcomes even more effectively and at a lower cost than individual appointments [https://pubmed.ncbi.nlm.nih.gov/33849860/].

What is Functional Medicine and Why Does it Matter?

Functional medicine is a healthcare model that focuses on identifying and addressing the root causes of chronic diseases. Instead of treating symptoms in isolation, this approach considers the complex interplay of genetic, environmental, and lifestyle factors unique to each patient. It views the body as an interconnected system, where imbalances in one area can impact overall health. This perspective is vital because many chronic conditions stem from multiple contributing factors that conventional medicine may not fully address. By delving deeper into a patient's history, diet, stress levels, and environmental exposures, functional medicine aims to restore balance and promote long-term well-being.

The Core Principles of Functional Medicine

Functional medicine operates on several core principles that differentiate it from traditional care. First, it is patient-centered, meaning that care is tailored to the individual, not just their disease. This involves a detailed understanding of each patient’s story, including their experiences, preferences, and unique health challenges. Second, it is an integrative, science-based healthcare approach. It combines modern medical science with a deep understanding of human physiology and biochemistry to develop personalized treatment plans. Third, functional medicine emphasizes the dynamic balance of internal and external factors. This includes diet, exercise, stress, toxins, and relationships, all of which can influence health.

Addressing Root Causes

The primary goal of functional medicine is to uncover the underlying causes of illness. For instance, instead of prescribing medication for high blood pressure, a functional medicine practitioner might investigate factors like chronic stress, dietary choices, gut health, or toxin exposure that could be contributing to the elevated readings. This root-cause approach can lead to more sustainable health improvements. This is particularly relevant for chronic conditions where symptoms often mask deeper systemic issues. By addressing these fundamental imbalances, patients can experience significant improvements in their health.

Personalized Lifestyle Medicine

A key component of functional medicine is personalized lifestyle medicine. This involves creating highly individualized recommendations for nutrition, exercise, stress management, and sleep. The idea is that there is no one-size-fits-all solution for health. What works for one person may not work for another, even if they have the same diagnosis. This personalized approach is supported by research, which highlights the relevance of personalized lifestyle medicine for nutrition and lifestyle recommendations [https://pubmed.ncbi.nlm.nih.gov/23878520/]. This level of customization ensures that interventions are more effective and sustainable for the individual. The commitment to personalized care helps patients make lasting changes that support their health goals.

The Cleveland Clinic’s Center for Functional Medicine, for example, embodies this model, offering care that aims to address the root causes of chronic disease [https://newsroom.clevelandclinic.org/2019/10/25/cleveland-clinic-study-finds-functional-medicine-model-is-associated-with-improvements-in-health-related-quality-of-life]. Their research shows how this focus can lead to measurable improvements in how patients feel and function in their daily lives. The emphasis on individualized care and addressing underlying factors makes functional medicine a powerful tool for those seeking comprehensive and lasting health solutions. This focus on the individual helps patients feel heard and understood, fostering a stronger partnership in their health journey.

Does Functional Medicine Improve Health-Related Quality of Life?

Yes, functional medicine has been associated with significant improvements in health-related quality of life, according to research from the Cleveland Clinic. A two-year retrospective cohort study, published in JAMA Network Open, was the first of its kind to investigate the impact of the functional medicine model on patient well-being [https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2753520]. This study compared patients treated at Cleveland Clinic’s Center for Functional Medicine with those receiving care in a primary care setting. The findings suggest that functional medicine can lead to beneficial and sustainable improvements in how patients experience their physical health.

Measuring Health-Related Quality of Life

To assess health-related quality of life, researchers used the Patient-Reported Outcome Measurement Information System (PROMIS®) questionnaire. This tool, validated by the National Institutes of Health (NIH), provides a comprehensive measure of patients' global physical and mental health. PROMIS tracks various factors that impact daily life, including fatigue, physical function, pain, gastrointestinal issues, and emotional well-being. By monitoring these scores over time, researchers could objectively evaluate the effectiveness of the functional medicine model compared to traditional primary care. The ability to measure these diverse aspects of health allows for a holistic understanding of patient improvement.

Key Findings from the Cleveland Clinic Study

The study involved 1,595 patients from the Center for Functional Medicine and 5,657 patients from a family health center providing primary care. At the six-month mark, patients treated by the Center for Functional Medicine showed significantly greater improvements in their PROMIS global physical health scores compared to those in primary care. Specifically, approximately 31% of functional medicine patients improved their PROMIS global physical health scores by 5 points or more. This 5-point improvement is considered a clinically meaningful change, indicating a noticeable positive effect on daily life. In contrast, only 22% of primary care patients achieved a similar improvement in their scores over the same period [https://newsroom.clevelandclinic.org/2019/10/25/cleveland-clinic-study-finds-functional-medicine-model-is-associated-with-improvements-in-health-related-quality-of-life].

Sustained Improvements Over Time

The benefits observed in functional medicine patients were not just short-lived. At 12 months, patients seen by the Center for Functional Medicine continued to show improvements in PROMIS global physical health scores, similar to those seen at six months. While these 12-month improvements were not significantly larger when directly compared to primary care patients in the broader cohort, a closer look at a smaller group of patients who had scores at both 6 and 12 months revealed sustained and significantly larger improvements in PROMIS global physical health in the functional medicine group compared to primary care. This suggests that the functional medicine model can lead to lasting positive changes in physical well-being. For more details, see Cleveland Clinic functional medicine study.

Broader Impact on Well-being

While the primary focus was on physical health, the PROMIS questionnaire also assesses global mental health. The study’s findings suggest that the comprehensive, root-cause approach of functional medicine may indirectly support mental well-being as physical health improves. When individuals experience less pain, fatigue, and better physical function, their emotional well-being often follows suit. This holistic impact on health-related quality of life underscores the value of functional medicine in helping patients not only manage their conditions but also thrive in their daily lives. "In the first retrospective cohort study of the functional medicine model, Cleveland Clinic researchers found that functional medicine was associated with improvements in health-related quality of life," noted Michelle Beidelschies, Ph.D., from the Cleveland Clinic [https://newsroom.clevelandclinic.org/2019/10/25/cleveland-clinic-study-finds-functional-medicine-model-is-associated-with-improvements-in-health-related-quality-of-life]. This foundational research provides strong evidence for the benefits of this care model.

How Do Shared Medical Appointments (SMAs) Affect Outcomes?

Shared medical appointments (SMAs) in functional medicine have been shown to improve patient outcomes more effectively and are less costly to deliver than individual appointments. This was a key finding from another Cleveland Clinic study, published in BMJ Open [https://pubmed.ncbi.nlm.nih.gov/33849860/]. SMAs offer a group-based approach to care, where patients with similar chronic conditions meet together with a healthcare provider. This model fosters a supportive community environment, allowing patients to learn from each other's experiences and receive comprehensive education on lifestyle interventions.

The Cleveland Clinic's Functioning For Life® Program

The Cleveland Clinic Center for Functional Medicine offers a specific SMA program called Functioning For Life® (FFL). This 10-week program is designed to address various chronic conditions by emphasizing "food as medicine." Through structured sessions, patients learn about nutrition, healthy lifestyle choices, and practical strategies for implementing these changes in their daily lives. The FFL program empowers patients to take an active role in their health, enabling them to make positive decisions about food and become advocates for healthy lifestyles within their homes and communities [https://newsroom.clevelandclinic.org/2021/04/13/cleveland-clinic-study-finds-functional-medicines-shared-medical-appointments-deliver-improved-patient-outcomes-at-less-cost]. This group setting often provides a sense of accountability and shared purpose that can be highly motivating.

Comparing SMAs to Individual Appointments

The retrospective cohort study assessed 2,455 patients who participated in either in-person SMAs or individual appointments between March 2017 and December 2019. To ensure a fair comparison, researchers propensity score-matched 213 pairs of patients, balancing factors such as age, sex, race, marital status, income, body mass index (BMI), blood pressure, baseline PROMIS scores, and functional medicine diagnostic category. This rigorous matching process helped to isolate the effect of the care delivery model itself. The primary outcome measured was the change in PROMIS Global Physical Health (GPH) at three months, with secondary outcomes including changes in PROMIS Global Mental Health (GMH), biometrics, and cost.

Improved Physical and Mental Health Outcomes

The results were compelling. Among the 213 matched pairs, patients in SMAs demonstrated greater improvements in PROMIS GPH T-scores at three months, with a mean difference of 1.18 (95% CI 0.14 to 2.22, p=0.03) compared to patients in individual appointments. This indicates a statistically significant and clinically relevant improvement in physical health for SMA participants. Furthermore, SMA patients also exhibited greater improvements in PROMIS GMH T-scores, with a mean difference of 1.78 (95% CI 0.66 to 2.89, p=0.002) at three months. This suggests that the group-based functional medicine approach positively impacts both physical and mental well-being.

Additional Health Benefits and Cost Savings

Beyond self-reported health, SMA patients experienced greater weight loss than those in individual appointments, with a mean difference of -1.4 kg (95% CI -2.15 to -0.64, p<0.001). Both groups, however, saw a similar improvement of 5.5 mm Hg in systolic blood pressure, indicating that both care models can positively impact certain biometric markers. Critically, the study also found that SMAs were less costly to deliver than individual appointments, making this model a potentially more efficient way to provide functional medicine care. "SMAs deliver functional medicine-based care that improves outcomes more than care delivered in individual appointments and is less costly to deliver," stated Michelle Beidelschies, Ph.D., one of the lead researchers [https://newsroom.clevelandclinic.org/2021/04/13/cleveland-clinic-study-finds-functional-medicines-shared-medical-appointments-deliver-improved-patient-outcomes-at-less-cost]. This dual benefit of better outcomes and lower cost makes SMAs a promising avenue for expanding access to functional medicine.

What Are the Differences Between Functional Medicine and Traditional Primary Care Patients?

The Cleveland Clinic study that examined the association of the functional medicine model with health-related quality of life also revealed notable demographic differences between patients seeking functional medicine care and those seen in traditional primary care settings. These differences are important because they might influence the observed health improvements and help researchers understand who is currently accessing and benefiting from functional medicine. Understanding these patient characteristics can inform future outreach and care strategies.

Demographic Disparities

The study included 1,595 patients from the Center for Functional Medicine and 5,657 patients from a family health center. When comparing these two groups, several demographic distinctions became clear. The mean age of functional medicine patients was 49.4 years, which was younger than the mean age of 55.4 years for primary care patients. A significant majority of functional medicine patients were women, accounting for 81.5% of the cohort, compared to 61.5% in primary care. In terms of race, 92.4% of functional medicine patients identified as white, whereas 85.0% of primary care patients were white. Functional medicine patients also had a lower median household income, at $59,286.0, compared to $72,874.0 for primary care patients [https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2753520]. These differences suggest that those who seek functional medicine may represent a distinct demographic profile.

Differences in Chronic Conditions

Beyond demographics, the study also highlighted differences in the prevalence of certain chronic conditions between the two patient groups. A smaller percentage of functional medicine patients had diabetes (17.9%) compared to primary care patients (34.1%). Similarly, hypertension was less common among functional medicine patients, affecting 19.2% of the group, while it was present in 50.9% of primary care patients. The prevalence of depression was similar in both groups, with 25.8% of functional medicine patients and 24.1% of primary care patients reporting depression. These disparities in chronic disease burden could influence baseline health statuses and how patients respond to different care models. For more details, see Shared medical appointments study.

Implications for Research and Practice

These observed differences suggest that patients who seek functional medicine may have different health priorities, socioeconomic backgrounds, or stages of chronic disease compared to those who primarily use traditional primary care. For instance, the younger age and lower prevalence of conditions like diabetes and hypertension in the functional medicine group might mean they are seeking care earlier in their disease progression or are more proactive about their health. These factors could contribute to their ability to achieve significant improvements in health-related quality of life. Future prospective studies are needed to further examine the functional medicine model of care and long-term outcomes, taking these patient characteristics into account. Understanding these nuances will help researchers determine how generalizable the benefits of functional medicine are across different populations and how to best tailor care. The fact that functional medicine patients often present with different health profiles emphasizes the need for personalized approaches to healthcare, which is a cornerstone of the functional medicine model.

Is Personalized Lifestyle Medicine Key to Root-Cause Healing?

Yes, personalized lifestyle medicine is a fundamental component of root-cause healing within the functional medicine framework. This approach recognizes that each individual's health is influenced by a unique combination of genetic predispositions, environmental exposures, and lifestyle choices. Therefore, effective healing requires interventions that are specifically tailored to these individual factors, rather than a generalized treatment plan. Functional medicine practitioners delve deep into a patient's history, diet, physical activity, stress levels, sleep patterns, and social connections to identify specific areas for intervention. This comprehensive assessment allows for the creation of highly individualized recommendations that target the true origins of health imbalances.

Tailoring Nutrition and Lifestyle Recommendations

At the heart of personalized lifestyle medicine are customized nutrition and lifestyle recommendations. This means moving beyond generic dietary advice to consider a patient's unique biochemical needs, food sensitivities, gut microbiome, and metabolic profile. For example, a patient struggling with inflammation might receive a specific anti-inflammatory diet plan, while another with blood sugar dysregulation might focus on different macronutrient ratios and timing of meals. These recommendations extend to other lifestyle areas, such as personalized exercise routines designed to support energy levels and reduce stress, or specific sleep hygiene protocols to improve restorative rest. The goal is to optimize the body's natural healing capabilities by providing it with the precise support it needs. Research confirms the relevance of personalized lifestyle medicine for nutrition and lifestyle recommendations, emphasizing its role in effective care [https://pubmed.ncbi.nlm.nih.gov/23878520/].

Addressing Obesity-Related Cancers and Chronic Conditions

Personalized lifestyle interventions are not just for general wellness; they are also crucial for the prevention and treatment of severe chronic conditions, including obesity-related cancers. The understanding that lifestyle factors play a significant role in disease progression underscores the importance of a tailored approach. By addressing individual risk factors through personalized diet, exercise, and other lifestyle modifications, functional medicine aims to mitigate disease risk and support treatment outcomes. For example, specific nutritional protocols and physical activity plans can be developed to help patients manage weight, reduce inflammation, and improve metabolic health, all of which are critical in the context of obesity-related cancers [https://pubmed.ncbi.nlm.nih.gov/40282431/]. This proactive and individualized strategy offers a powerful tool in the fight against complex diseases.

Empowering Patients for Lasting Change

A key aspect of personalized lifestyle medicine is patient empowerment. When patients understand how their unique lifestyle choices impact their health, they become active participants in their healing journey. Functional medicine practitioners act as guides, educating patients and providing them with the tools and knowledge to make informed decisions. This collaborative approach fosters greater adherence to treatment plans and promotes sustainable lifestyle changes. The Functioning For Life® shared medical appointment program at the Cleveland Clinic, for instance, is designed to empower patients to make positive decisions regarding food and become advocates for healthy lifestyles within their homes and communities [https://newsroom.clevelandclinic.org/2021/04/13/cleveland-clinic-study-finds-functional-medicines-shared-medical-appointments-deliver-improved-patient-outcomes-at-less-cost]. This empowerment is vital for achieving long-term root-cause healing, as it equips individuals with the skills to maintain their health improvements independently.

What Does the Future Hold for Functional Medicine Research?

The initial research from the Cleveland Clinic provides strong evidence for the positive impact of functional medicine on health-related quality of life and the effectiveness of shared medical appointments. However, these studies also highlight areas for future investigation, emphasizing the need for more comprehensive and long-term research. Researchers believe that the improvements seen in functional medicine patients could be due to a combination of factors, including the unique aspects of the functional medicine model itself, the types of patients who seek this care, and their adherence to treatment or belief in the model. Further studies are essential to fully understand these dynamics and solidify the evidence base for functional medicine.

The Need for Prospective Studies

The Cleveland Clinic's initial study on health-related quality of life was a retrospective cohort study. While valuable, retrospective studies look back at existing data. To build an even stronger case and understand cause-and-effect relationships more clearly, future prospective studies are needed. Prospective studies follow groups of individuals over time, allowing researchers to observe outcomes as they unfold. This type of research can provide more definitive answers about the long-term effectiveness of functional medicine, including how durable the health improvements are over many years. It will also help to control for potential confounding factors and provide a clearer picture of the model's direct impact.

Examining Specific Components of the Model

Future research could also focus on dissecting specific components of the functional medicine model. For example, studies could investigate the impact of particular dietary interventions, stress reduction techniques, or detoxification protocols on patient outcomes. By isolating these elements, researchers can gain a deeper understanding of which interventions are most effective for different conditions and patient populations. This level of detail will help refine functional medicine protocols and identify best practices. The comprehensive nature of functional medicine means there are many variables to explore, from specific diagnostic categories to the duration and intensity of lifestyle changes.

Understanding Patient Characteristics and Adherence

The Cleveland Clinic study noted differences between functional medicine patients and primary care patients, such as age, gender, and the prevalence of certain chronic conditions. Future research should explore how these patient characteristics influence outcomes. For instance, are younger patients more likely to adhere to complex lifestyle changes? Does a strong belief in the functional medicine philosophy lead to better results? Understanding these factors will help practitioners identify which patients are most likely to benefit from functional medicine and how to support patient adherence more effectively. This could involve developing personalized support strategies to help patients overcome barriers to treatment adherence. For more details, see JAMA Network Open functional medicine research.

Long-Term Outcomes and Cost-Effectiveness

While the shared medical appointment study showed SMAs are less costly to deliver and improve outcomes at three months, more research is needed on the long-term cost-effectiveness of functional medicine. This includes evaluating healthcare utilization, medication reduction, and overall quality of life over extended periods. Demonstrating long-term benefits and cost savings will be crucial for broader acceptance and integration of functional medicine into mainstream healthcare systems. Michelle Beidelschies, Ph.D., emphasized the importance of these findings, stating that SMAs "deliver functional medicine-based care that improves outcomes more than care delivered in individual appointments and is less costly to deliver" [https://pubmed.ncbi.nlm.nih.gov/33849860/]. Further studies will build on this foundation, providing a more complete picture of the value functional medicine brings to patient care.

Frequently Asked Questions

What is the main goal of functional medicine?

The main goal of functional medicine is to identify and address the root causes of chronic disease, rather than just managing symptoms. It takes a patient-centered approach, considering each person's unique genetic, environmental, and lifestyle factors to create personalized treatment plans. This holistic view aims to restore balance and promote long-term health, as demonstrated by studies showing functional medicine's association with improvements in health-related quality of life [https://newsroom.clevelandclinic.org/2019/10/25/cleveland-clinic-study-finds-functional-medicine-model-is-associated-with-improvements-in-health-related-quality-of-life].

How was health-related quality of life measured in the Cleveland Clinic study?

Health-related quality of life in the Cleveland Clinic study was measured using the Patient-Reported Outcome Measurement Information System (PROMIS®) questionnaire. This NIH-validated tool assesses various aspects of global physical and mental health, including fatigue, physical function, pain, gastrointestinal issues, and emotional well-being. By tracking PROMIS scores, researchers could quantify improvements in patients' daily lives, with 31% of functional medicine patients showing a clinically meaningful 5-point or more improvement in physical health at 6 months [https://newsroom.clevelandclinic.org/2019/10/25/cleveland-clinic-study-finds-functional-medicine-model-is-associated-with-improvements-in-health-related-quality-of-life].

What is a 'clinically meaningful change' in PROMIS scores?

A "clinically meaningful change" on PROMIS Global Health T-score scales is defined as an improvement of 5 or more points. This threshold indicates a noticeable and significant effect on a patient's daily life, meaning the change is substantial enough to be felt by the individual. In the Cleveland Clinic study, 31% of functional medicine patients achieved this clinically meaningful improvement in their PROMIS global physical health scores at 6 months [https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2753520].

Are shared medical appointments more effective than individual appointments in functional medicine?

Yes, shared medical appointments (SMAs) have been found to deliver improved outcomes compared to individual appointments in functional medicine. A Cleveland Clinic study found that patients in SMAs exhibited greater improvements in both PROMIS Global Physical Health T-scores (mean difference 1.18) and PROMIS Global Mental Health T-scores (mean difference 1.78) at 3 months. SMAs were also less costly to deliver and resulted in greater weight loss (mean difference -1.4 kg) [https://pubmed.ncbi.nlm.nih.gov/33849860/].

What chronic conditions does functional medicine address?

Functional medicine aims to address the root causes of a wide range of chronic conditions. While the Cleveland Clinic studies focused on general chronic conditions and health-related quality of life, the model's personalized approach allows it to be applied to various issues. For example, the Functioning For Life® SMA program addresses "various chronic conditions through the use of food as medicine" [https://newsroom.clevelandclinic.org/2021/04/13/cleveland-clinic-study-finds-functional-medicines-shared-medical-appointments-deliver-improved-patient-outcomes-at-less-cost]. This includes conditions where diet, lifestyle, and environmental factors play a significant role, such as metabolic disorders, autoimmune diseases, and gastrointestinal issues.