The Ultimate Guide to Functional Medicine

Min Read
Medically Reviewed
Key Takeaways

The goal of functional medicine is to find the root cause of chronic illnesses.

Functional medicine provides care that is patient-centered, holistic, personalized, and preventive. 

Functional medicine practitioners get to know their patient’s lifestyle, emotional and mental wellbeing, and medical history, and recommend lifestyle adjustments in addition to science-based treatments.

Medically Reviewed By
Dr. Deb Matthew
Written By
WellTheory Team

Functional medicine is on the rise, but what is this therapeutic approach, and how did it come to be? It all started with alternative medicine, now often called complementary and alternative medicine (CAM), which is therapy used in place of conventional medicine to treat disease. Alternative medicine is known for its holistic approach and addresses an individual’s mind, body, and spirit. A common example of alternative medicine is acupuncture. On the other hand, conventional medicine does just what its name says: treats diseases in a conventional way, often through the use of prescription drugs and surgeries. 

These divergent therapeutic approaches were later combined to form integrative medicine, which merges the holistic care of alternative medicine with science-based conventional therapies. Functional medicine is a type of integrative medicine. In this article, we will deep-dive into the history of functional medicine, what functional medicine practitioners do, and ways functional medicine can help you improve your quality of life. (Source)

What Is Functional Medicine?

The term “functional medicine” was coined by a group led by Jeffrey Bland, a biochemist who wanted to bridge the gap between alternative medicine and conventional medicine. Bland believed that illness is caused by underlying problems in an individual’s “biological network.”

Bland discusses this biological network as the interplay between an individual’s genes, lifestyle, and environment. If one of these components is not functioning properly, it could lead to disease. Keeping with this idea, it makes sense to look within an individual’s biological network to find the underlying causes of disease and restore health. (Source)

Functional medicine is also specific. Functional medicine practitioners look at an individual’s unique genome, or the collection of genes in their body, and lifestyle. From there, functional medicine practitioners suggest specialized treatment options tailored to the individual.

In this sense, functional medicine is quite different from conventional medicine, which is generally not individualized and instead works by grouping symptoms into different disease categories. 

The Four Pillars of Functional Medicine

Functional medicine is unique in its approach to treating disease and can be described by four main pillars, or foundational supports.  

Functional Medicine Is Patient-Centered

Right now, many conventional treatments are disease-centered. Disease-centered treatments work by identifying your symptoms, matching the symptoms to a known disease, and then following the same treatment plan given for everyone with that disease.

However, problems may arise because no two people are the same. Every individual has a different lifestyle, genes, and background shaping their disease. Unlike conventional medicine, functional medicine focuses on the patient. It is important for functional medicine practitioners to look at your unique background in order to fully understand your disease. 

Functional Medicine Is Holistic

Functional medicine practitioners look at you as a whole person. Many different components, such as genes and an individual’s environment, affect health. By looking at you holistically, functional medicine practitioners can take advantage of many more therapies than would have been available through conventional medicine.

For example, functional medicine addresses your lifestyle and can suggest lifestyle or dietary changes to aid in treating a disease. There is evidence that holistic therapies are the most effective approach to treating diseases, because many diseases are caused by an interplay between genes and the environment. 

Functional Medicine Is Personalized

Functional medicine practitioners run specific tests that look at your unique genome, your environment, and your lifestyle choices that may have led to a chronic disease or illness. Practitioners then develop a personalized treatment plan that is tailored to your health history and can help you to better manage a chronic disease.

Since we each have different genes and biological processes occurring in our bodies, it is important to account for these differences and design a treatment or management plan that best suits the individual. 

Functional Medicine Is Preventive 

Functional medicine is also focused on promoting long-term health. Functional medicine practitioners look at sustainable choices you can make that will allow you to manage your disease and maintain your long-term health.

Instead of simply treating your disease and moving on, functional medicine practitioners figure out what went wrong to begin with and give tips on how you can prevent it from happening again. (Source, Source)

hands wrapped around each other

How Does Functional Medicine Work?

Functional medicine practitioners have developed a functional medicine model to help identify the cause of a patient’s symptoms and design individualized treatment.

Step 1: Deep Dive Into You 

First, a functional medicine practitioner will look into your medical history and develop a timeline of your life. They will ask you about lifestyle factors such as sleep, relaxation, relationships, nutrition, stress, and exercise.

They will also take a close look at your emotional, mental, and spiritual health, because these areas affect your physical health. Along the way, the functional medicine practitioner will identify cause–effect relationships and issues that might have led to your symptoms. 

The goal at this step is simply to explore your health background. By asking all these questions, functional medicine practitioners are able to pinpoint problem areas that other health care professionals might overlook. (Source)

Step 2: Tests

Next, many different laboratory tests may be performed to check for imbalances. Many of these tests are non-invasive. 

  • Food sensitivity and intolerance tests can be performed to test for evidence of a digestive condition. 
  • Hair tests can be done to test for sufficient levels of nutrients such as vitamins and minerals in your body. Consuming a diet low in important nutrients can lead to malnutrition, nutrient deficiencies, and disease. 
  • Antioxidant tests are used to test for free radicals in your body, which may aggravate certain diseases such as cancer and heart disease. 
  • Candida testing can test for overgrowths of a yeast known as Candida albicans, which can cause yeast infections and disrupt your gut microbiome.  
  • Antibody tests are used to confirm a diagnosis if you appear to be experiencing symptoms of autoimmune disease. 
  • An adrenal stress profile maps your stress levels throughout the day and is used to test adrenal dysfunction. 

A physical examination is also often performed by a functional medicine practitioner to check for proper nutrition. (Source, Source)

Step 3: Personalized Treatment

The final step is for the functional medicine practitioner to talk through your results with you. They may suggest lifestyle adjustments such as exercising more consistently, managing stress levels, or removing from your diet certain foods that trigger symptoms.

The functional medicine practitioner may also prescribe vitamin and mineral supplements to fix a nutrient deficiency. Finally, they might recommend beneficial practices such as yoga or meditation to supplement your treatment. 


Overall, treatment by a functional medicine practitioner should allow you to: 

  • feel empowered and engaged in your own treatment plan
  • have insightful, in-depth conversations with a highly trained professional 
  • have a voice in the decision-making process 

(Source, Source)

Who Is Functional Medicine For?

Functional medicine can help anyone who wants to improve their overall health, as well as those interested in disease prevention and stress management.

However, functional medicine is more commonly used to treat or manage chronic illnesses, such as: 

  • autoimmune diseases 
  • arthritis 
  • asthma 
  • digestive disorders
  • food allergies
  • diabetes
  • thyroid disorders 

Functional medicine can also help manage women’s health issues such as:

  • premenstrual syndrome (PMS) 
  • polycystic ovary syndrome (PCOS) 
  • negative symptoms associated with menopause 

(Source)

happy woman in sunflower field

Is Functional Medicine Science-Based?

Yes! Functional medicine treatments follow the same scientific guidelines as conventional medicine treatments, while taking a more patient-centered approach and offering science-backed alternative treatments.

These alternative practices are meant to help patients manage chronic conditions and improve their overall health. However, these alternative practices must be used appropriately and in a way that will facilitate the healing process. 

It’s important to remember that functional medicine practitioners do not accept alternative medicine unquestioningly or without scientific evidence. Functional medicine practices are rooted in science and supported by research. (Source)

Food as Medicine 

If you have an autoimmune disease or other chronic condition, consider following an anti-inflammatory diet to help improve your gut health. A great, easy way to manage your chronic condition or lower your risk of developing chronic conditions is to eat a balanced, nutritious diet. 

  • Get your daily fruits and vegetables to reduce inflammatory markers in your body and lower oxidative stress. Oxidative stress is caused by an imbalance of free radicals in the body that can eventually damage cells and tissues.
  • Include whole grains and lean meats in your diet. These foods can reduce your risk of developing heart disease. Whole grain carbohydrates can also reduce inflammation in the body. 
  • Try following the Mediterranean diet. This diet is rich in natural foods such as fruits and vegetables and low in processed foods. There is strong evidence that following the Mediterranean diet can reduce inflammation and your risk of developing certain diseases. 
  • Consume foods rich in unsaturated fatty acids, because there is evidence that unsaturated fatty acids can reduce inflammation. Foods such as avocados, almonds, fish, sesame seeds, and walnuts are great sources of unsaturated fatty acids. On the other hand, there is mixed evidence on whether saturated fatty acids may increase inflammation. More research must be conducted to draw the line between harmful and healthy fatty acid types. 
  • Add extra virgin olive oil to your dinner. Extra virgin olive oil is an example of an unsaturated fatty acid. This fatty acid can reduce inflammation and there is evidence that extra virgin olive oil can reduce the risk of heart problems in individuals who are at risk of cardiovascular disease. 
  • Don’t eat too much red meat. Red meat is linked to cardiometabolic diseases (high blood pressure, high blood sugar, obesity, elevated triglycerides) and should be consumed in moderation. 

(Source, Source, Source)

bruschetta on a serving board

Lifestyle Changes

In addition to diet suggestions, a functional medicine clinician may also suggest lifestyle changes. One common suggestion is to lower your stress levels. Evidence shows that around 75% to 90% of diseases are linked to chronic stress. Stress also impairs the inflammatory response, which can lead to autoimmune diseases. However, there are many steps you can take to reduce your stress today. (Source)

Exercise Regularly 

Set aside a few minutes each day to go for a jog, take a walk, or practice yoga. Exercise reduces cellular aging and oxidative stress, and allows you to respond better to psychological stressors. Exercise also lowers your risk of cardiometabolic diseases. (Source)

Meditate 

Practice mindfulness, or the act of being in the present moment and accepting thoughts or emotions without judgment. There is evidence that meditation and mindfulness can reduce stress and lower your risk of anxiety and depression. (Source)

Catch Some Z’s

Your body relies on sleep to manage stress and fight infections. Sleep deprivation can increase stress levels and your risk of developing cardiovascular diseases and diabetes. Sleep deprivation can also hurt your metabolism and increase your risk of developing an eating disorder. There are many resources available to improve your quality of sleep. (Source)

Why Should I Try Functional Medicine? 

It’s important to note that functional medicine builds on alternative medicine, some of which is still unproven. Research continues into the safety and science behind these alternative practices.

That said, generally functional medicine:

  • humanizes and strengthens patient-practitioner relationships. Functional medicine practitioners spend time getting to know their patients holistically. If you would like more personalized treatments and in-depth conversations with a health care professional about your individual needs, consider seeing a functional medicine practitioner. 
  • allows you to take charge of your health. Currently, U.S. healthcare is mostly disease-focused and relies on brief visits to quickly treat diseases. Not only is functional medicine used to get to the root cause of a disease, but functional medicine offers patients valuable insight into lifestyle changes they can make to prevent later diseases.
  • looks at your health from all angles. Unlike conventional medicine, functional medicine dives deep into your history, stress levels, diet, and overall wellbeing to figure out the cause of your symptoms. It is helpful to look at all of these aspects of your life, because problems in any of them can negatively affect your physical health. 
  • is less invasive. Functional medicine is unique in that it uses alternative practices to help you manage your condition. These alternative treatments are science-based and will likely have fewer side effects than conventional drug treatments. 

(Source)

When Should I See a Functional Medicine Practitioner?

It may be helpful to see a functional medicine practitioner when you:

  • are experiencing symptoms of a chronic condition, or receive a diagnosis for a chronic condition, and want to get to the root cause of your condition 
  • want to incorporate science-based alternative medicine into your life to help you manage disease 
  • want guidance from a health care professional in making lifestyle changes that will help you live a healthy life 

Where Can I Find the Best Resources About Functional Medicine?

Outside of WellTheory’s Ultimate Guide to Functional Medicine, we recommend looking at:

What’s the Bottom Line on Functional Medicine?

Functional medicine is a therapeutic approach combining conventional medicine and alternative practices to find the root cause of disease and treat it holistically. Functional medicine practitioners spend time learning about their patients, and design personalized treatment plans that include using dietary and lifestyle adjustments to improve health.  


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