Are at-home food tests selling you more than just the kit?

As the field of health tech expands and people are interested in taking more control over their health, at-home tests promising in-depth information about your body are now available. From microbiome tests to food-sensitivity exams, they claim that following their recommended dietary changes can help people overcome chronic migraines, bloating, gas, insomnia, anxiety, weight gain, and more. 

These tests may sound amazing, but are they too good to be true? We’ve put together some of the recent research behind these body processes for you to check out. 

Are at-home food sensitivity tests worth it? 

The first thing we need to cover is what a food sensitivity actually is. Unlike a food allergy, food sensitivity is not a recognized medical condition. Some people use the term sensitivity to group together uncomfortable but not life-threatening symptoms a person experiences after eating a specific food. For example, a lactose-intolerant person who drinks milk will likely experience bloating or gas, but they aren’t having an allergic reaction. 

The second thing we need to cover is the difference between a doctor-provided food allergy exam and an at-home food sensitivity test. If you think you may have a food allergy, your primary care physician can refer you to an allergist. They use several different tests to provide answers, including IgE exams and skin testing. During an IgE exam, a lab tech exposes certain foods to a blood sample and examines how much of a specific antibody, immunoglobulin E (IgE), is generated. If the IgE levels are higher than normal, this can be a sign that a person is allergic to the food. They’ll typically only test a few foods instead of a majority of food types. Based on the findings, the allergist may recommend additional testing to confirm the results. 

The typical at-home food sensitivity test is a bit different. These take a blood sample and measure how much immunoglobulin G (IgG) binds to different types of foods. As with any foreign entity in the body, the immune system reacts to the foods you eat. Your immune system responds to any food you consume by creating IgG, so having this antibody is not necessarily a sign of food allergy. In one study, participants ate 12 different foods. Every participant had antibodies related to the food, yet none reported any symptoms. The researchers conclude that these antibodies are just an average response to eating. Another study exposed three groups to ovalbumin, a type of protein: those who are allergic, those who had overcome an allergy to the protein, and those who were not allergic. All three had similar IgG responses. 

What can a gut microbiome test tell me? 

The gut microbiome is the diverse colony of bacteria and viruses that live in your gut. They metabolize the food you eat and produce byproducts, which may include neurotransmitters like serotonin and other essential chemicals. Everyone has a different microbiome, so at-home tests are based on the idea that learning which bacteria are living in your gut can enable you to eat the right foods to fuel the beneficial members and get rid of the not-so-great ones. 

To take one of these tests, you purchase a kit, register it online, and then collect a stool sample, which you ship to a lab. A few weeks later, you receive an analysis of all the organisms in your microbiome, as well as dietary and probiotic recommendations. 

However, research has shown that the organisms living in your microbiome can change daily, even when you eat the exact same foods every day. This means that the test results will provide context just to the specific moment in time when you produced the stool sample, and their dietary recommendations may not have major influences on your health. 

Should I purchase a dietary at-home health test? 

Since the research behind these tests is questionable and many carry a pretty hefty price tag, we recommend skipping these exams. If you are experiencing concerns like chronic migraines, unexplained weight gain, anxiety, or insomnia, schedule an appointment with a Baylor St. Luke’s Medical Group primary care physician. They can review your symptoms, lifestyle, and health history to find potential causes and recommend diagnostic tests and treatments. 

Sources:

NCBI | Blood testing for sensitivity, allergy or intolerance to food
Academy of Nutrition and Dietetics | Are Food Sensitivity Tests Accurate?
Medical News Today | Microbiome tests: What to know
NCBI | Role of immunoglobulin G antibodies in diagnosis of food allergy
New York Times | Should You Get a Microbiome Test?
Healthline | What's Possible from Microbiome Testing at Home?
MIT News | Even on standardized diet, gut flora change from day to day