What kind of doctor tests for food allergies
EverlyWell’s food sensitivity tests exploit a frustrating fact for those wondering whether their symptoms stem from the food they eat: There is no simple way to discover an answer.
The doctor-advised approach is to cut common offenders from the diet one by one — a so-called elimination diet — but that is cumbersome, time-consuming, and, by its extremely nature, restrictive.
“It is hard to remove certain foods from the American diet, and people may desire a definitive way to know which foods cause symptoms without eliminating it,” said Dr. Christina Ciaccio, an allergist at the University of Chicago.
“Unfortunately, such a test doesn’t exist.”
In addition, cutting out entire food groups carries risks such as malnutrition, particularly in children. (EverlyWell does not offer tests to anyone under the age of 18.)
And, though rare, symptoms such as bloating or headaches can be a sign of something more sinister, such as cancer. That’s why an elimination diet is best conducted under physician supervision.
When a person sees the doctor to study about possible food intolerances, they’ll likely be irked to discover that the cash they spent on food sensitivity testing ordered online or at an “alternative” practitioner’s office was money below the drain.
“Most patients in the finish, when we own done our workup and come up with a plan,” Hartz said, “are actually fairly frustrated that they spent every this money on a useless test.”
This tale has been corrected to reflect the types of at-home blood tests offered by competitors.
To diagnose food allergies, your doctor first will talk to you about your reactions to certain foods and conduct a physical exam and detailed medical history. Skin prick tests or blood tests can be used to check for reactions to specific food allergens. An oral food challenge may be done if other testing is inconclusive. Ultimately, your doctor will use every this information to diagnose you with food allergies.
Referral to an allergy clinic
If your GP suspects a food allergy, you may be referred to an allergy clinic for testing.
The tests needed can vary, depending on the type of allergy:
- if the symptoms developed quickly (an IgE-mediated food allergy) – you’ll probably be given a skin-prick test or a blood test
- if the symptoms developed more slowly (non-IgE-mediated food allergy) – you’ll probably be put on a food elimination diet
During a skin-prick test, drops of standardised extracts of foods are placed on the arm.
The skin is then pierced with a small lancet, which allows the allergen to come into contact with the cells of your immune system.
Occasionally, your doctor may perform the test using a sample of the food thought to cause a reaction.
Itching, redness and swelling generally indicates a positive reaction.
This test is generally painless.
A skin-prick test does own a little theoretical chance of causing anaphylaxis, but testing will be carried out where there are facilities to deal with this – usually an allergy clinic, hospital, or larger GP surgery.
An alternative to a skin-prick test is a blood test, which measures the quantity of allergic antibodies in the blood.
Food elimination diet
In a food elimination diet, the food thought to own caused the allergic reaction is withdrawn from your diet for 2 to 6 weeks. The food is then reintroduced.
If the symptoms go away when the food is withdrawn but return once the food is introduced again, this normally suggests a food allergy or intolerance.
Before starting the diet, you should be given advice from a dietitian on issues such as:
- the food and drinks you need to avoid
- how you should interpret food labels
- if any alternative sources of nutrition are needed
- how endless the diet should final
Don’t attempt a food elimination diet by yourself without discussing it with a qualified health professional.
There are several shop-bought tests available that claim to detect allergies, but should be avoided.
- vega testing – claims to detect allergies by measuring changes in your electromagnetic field
- kinesiology testing – claims to detect food allergies by studying your muscle responses
- hair analysis – claims to detect food allergies by taking a sample of your hair and running a series of tests on it
- alternative blood tests (leukocytotoxic tests) – claim to detect food allergies by checking for the «swelling of white blood cells»
Many alternative testing kits are expensive, the scientific principles they are allegedly based on are unproven, and independent reviews own found them to be unreliable.
They should therefore be avoided.
When Julia Cheek walked onto the set of “Shark Tank,” her five potential investors wore their trademark scowls. Yet within minutes, their demeanor changed, eyebrows raised and heads nodding as they peppered her with questions about her company, EverlyWell, and its promise to revolutionize medical diagnostics.
“EverlyWell is transforming lab testing — a $25 billion market — to be simple, convenient, and useful for you,” she told the judges with a grin. Beside her sat a display of the company’s wares: mail-order test kits for everything from testosterone levels to sexually transmitted infections.
When Cheek left the stage, she had a unused $1 million commitment from investor Lori Greiner.
And the company is wowing more than just the television judges. EverlyWell garnered $6 million in sales final year, a spokeswoman said, and Cheek told the judges that this year they expected that to double.
But what EverlyWell describes as one of its best-sellers — a test for food sensitivity — is of dubious medical worth, according to experts interviewed by STAT. The $199 test promises to use a fingerprick’s worth of blood to gauge whether a person’s immune system is athletic against 96 common foods, including asparagus, garlic, and eggs. An immune protein called immunoglobulin G, the company’s website says, could be to blame for symptoms such headaches, stomach pain, diarrhea, and fatigue.
Other online vendors sell immunoglobulin G tests for food sensitivity as well, though none own reached EverlyWell’s degree of prominence.
Every are considered laboratory-developed tests, and are therefore not regulated by the Food and Drug istration.
Yet physician groups own for years advised against using immunoglobulin G tests to assess for so-called food sensitivities or intolerances. And allergy experts told STAT that the test is useless at best and could even cause harm if it leads customers to unnecessarily cut nutritious foods from their diet.
“EverlyWell believes providing this test aligns with relevant third-party research around the [immunoglobulin G] test’s usefulness in conjunction with an elimination diet,” the company said in a statement.
Booming industry, shaky science
EverlyWell’s test is just one entry to the booming field of at-home testing.
Alongside players in the genetic space, such as 23andMe and Color Genomics, upstarts are taking purpose at standard medical testing.
EverlyWell and competitors such as Thorne allow customers to take a little blood sample at home to run a variety of tests. Others offer a narrower range of products: Habit, for instance, focuses on nutrition; Blueprint for Athletes caters to fitness enthusiasts.
But in the sheer scope of its vision the most obvious analogue to EverlyWell is blood-testing startup Theranos, which also aimed to upend the laboratory testing industry.
At one point the company soared to a $9 billion valuation on its direct-to-consumer lab tests. But investigations revealed that its proprietary blood testing technology was deeply flawed, leading to a number of lawsuits; the company now is reportedly pivoting to medical devices.
Your doctor will likely enquire you to take several steps at home that will assist determine if you own a food allergy. These steps include keeping a food and symptom diary and, perhaps, participating in an elimination diet—both of which can provide helpful diagnostic information.
Keeping a Food Diary
If your doctor is unsure whether food is the cause of your symptoms, he or she may recommend that you hold a food diary.
A food diary can also be used to monitor dietary patterns to better pinpoint the cause of your symptoms.
The diary should be a finish record of not only the foods you've eaten over a given period of time (usually a week), but also an accurate record of the timing and characteristics of any symptoms you may own experienced.
Your doctor may go so far as to enquire you to record any activities you may own done prior to your symptoms to assess whether they may own contributed.
In some cases, stress and physical exertion can frolic as much a role in your symptoms as the foods you eat.
A food diary is often used in combination with other diagnostic tools or as a first step in opening an investigation.
Your doctor may put you on an elimination diet to assist pinpoint a food allergy.
While doctors will conduct an elimination diet in diverse ways, the basics are similar: Exclude the foods you suspect are causing your symptoms, take note of how you feel, and then reintroduce the foods after several days or weeks to see if symptoms reappear.
Elimination diets should only be done in consultation with your allergist, who should recommend what to avoid and for how endless.
Never reintroduce a food you suspect as having triggered an anaphylactic reaction.
Staying on an elimination diet might lead to nutritional imbalance.
What About At-Home Testing Kits?
You may be tempted to use at-home kits that test for food allergies.
If you do so, hold in mind that concerns over their accuracy own been raised, as they test for the incorrect type of antibodies (IgG instead of IgE) and are often falsely positive. This might lead you to unnecessarily avoid healthful foods.
To test or not to test
Food sensitivity is an umbrella term that encompasses symptoms that can arise, for example, from difficulty digesting a food, as in lactose intolerance, or susceptibility to the effect of a food, as in caffeine sensitivity.
These symptoms, however, do not involve an immune response. (Food allergies, on the other hand, own more serious symptoms and are driven by the immune system; validated tests for them do exist.)
Patients who enquire Dr.
Robert Wood, an allergist at Johns Hopkins Children’s Middle, whether they own a food sensitivity would never undergo an immunoglobulin G test. Immunoglobulin G tests “are completely useless and do dramatic harm” because they may compel patients to unnecessarily avoid wide swaths of a healthy diet, Wood said.
“In every my years of practice, I own never sent an immunoglobulin G test because they own no ability to predict food sensitivity,” he said.
That’s because immunoglobulin G stems from the body’s normal immune response to exposure to numerous substances, including food.
High levels don’t indicate a problem; they simply point to foods a person recently has eaten.
For these reasons, a 2008 European Academy of Allergy and Clinical Immunology task force recommended against testing for a type of immunoglobulin G to assess for food intolerance. In the report, the group wrote that the test was “irrelevant for the laboratory work-up of food allergy or intolerance and should not be performed in case of food-related complaints.”
In 2010, a subgroup of the American Academy of Allergy, Asthma & Immunology, or AAAAI, endorsed this recommendation. And two years later, the Canadian Society of Allergy and Clinical Immunology too released a position statement discouraging the use of the test.
The group noted that “positive test results … are to be expected in normal, healthy adults and children,” and that the test “increases the likelihood of untrue diagnoses … unnecessary dietary restrictions and decreased quality of life.”
A spokesperson for EverlyWell stated the company believes “there is a divergence of views regarding IgG tests,” and that the AAAAI does not speak for every health care providers.
The company pointed to a handful of little studies that own showed immunoglobulin G helped guide elimination diets — that is, trials of cutting certain foods out of the diet and gauging symptom improvement.
“IgG tests are currently ordered by thousands of medical providers in the U.S.” the spokesperson said.
Dr. Martha Hartz, an allergist at Mayo Clinic in Rochester, Minn., says she frequently evaluates patients who’ve already forked over the cash for the testing. “Anytime I see a patient who’s had these kinds of tests, we get them to throw it aside,” Hartz said.
“It has no relevance to anything. It is just not a test that should done.”