Bitter Green Aversion

"Your genetics affect the way you taste, and taste is an important factor in food choice."
"You have to consider how things taste if you really want your patient to follow nutrition guidelines."
"We're talking a ruin-your-day level of bitter when they tasted the test compound."
"These people [supertasters] are likely to find broccoli, brussels sprouts and cabbage unpleasantly bitter, and they may also react negatively to dark chocolate, coffee and sometimes beer."
"We thought they might take in more sugar and salt as flavour enhancers to offset the bitter taste of other foods, but that wasn't the case."
Jennifer Smith, postdoctoral fellow, cardiovascular science, University of Kentucky School of Medicine Lexington, Kentucky

activebeat

In any population there is a sub-set of people with superlative tasting abilities, thought to number between 25 to 30 percent of the population, according to Scientific American. Being a supertaster doesn't necessarily equate with enjoying food more because your taste is able to identify all manner of flavours, not when some flavours of a definitely bitter variety have their bitterness enhanced to the point of rank under-enjoyment.

No one would want to boast of their capacity to taste all the flavour nuances apparent to them in food choices when that ability teaches them to avoid bitter-tasting, albeit highly nutritional foods whose vitamin and mineral content is undeniably a healthy addition to any diet. A new study presented at the annual meeting of the American Heart Association pointed out that people genetically "hard-wired" to food sensitivity and bitterness will tend to avoid "heart-healthy" vegetables.

There may be plenty of people who would rather not have bitter greens such as arugula, endive and kale on their dinner plate, much less cruciferous vegetables such as dandelion greens, broccoli and brussels sprouts, but these truly are super-stars in nutritional quality. However, researchers have found the likely source of bitter-green vegetable aversion.

Greater number of tasteburds on supertaster tongue

One of some 25 bitter receptors on the tongue, TAS2R38 has two genetic variants: AV1 and PAV, of which researchers at the University of Kentucky School of Medicine, studying 175 people, discovered those who inherit two copies of PAV (supeertasters) are likelier to be susceptible to the flavours of bitter compounds such as sulphur in brussels sprouts, than people who inherit two copies of AVI (nontasters), or those who have one of each (average tasters); 40 to 50 percent of the population.

As a result of their super-sensitivity to bitter taste, supertasters are close to three times likelier to consume fewer vegetables than people without a pair of inherited PAV variants. Despite the researchers' expectations, it made little difference whether participants in their study were supertsters or not; fat, salt or sugar consumption remained the same for all their test subjects.

People genetically 'hardwired' to be more sensitive to bitter tastes eat fewer vegetables, according to a new study.  Getty Images

Scamming The Gullible With Food Tolerance Pseudoscience

"It's a normal physiological response [the creation of IgG, a 'memory' antibody forming post-vaccine exposures, infections or any other environmental exposure, including food] to the food we eat. Even if it is elevated -- and we don't even know what a 'normal' level is -- it doesn't indicate anything bad."
"If you eat a food you will produce IgG."
"[People could become obsessed] reading labels and taking extra precautions to make sure they don't have an accidental bite of a food they're not even sensitive to in the first place."
"... There is zero indication to ever just do a bunch of tests for random foods and see what you get." 
Dr. David Stukus, pediatric allergist, Nationwide Children's Hospital, Columbus, Ohio

"Many patients suffer from physical, psychological, and psychosomatic conditions for which conventional medicine cannot provide diagnosis or treatments."
"Such patients understandably turn to practitioners who tell them that these ailments are the result of ingestion of certain foods [assuring them that eliminating those foods based on sensitivity testing will erase symptoms. Many people feel better] because they feel like they have an explanation for their illness."
"Although it is important to be sympathetic with these patients, as scientists, it is also important for us to gently explain that these tests have not been validated by science."
Dr. John Kelso, Division of Allergy, Asthma and Immunology, Scripps Clinic, San Diego, Calif. Journal of Allergy and Clinical Immunology: In Practice

"It's just kind of thrown around loosely [food sensitivity], it's not a specific medical diagnosis."
"The labs are charging hundreds of dollars for these tests. I heard from one patient recently who paid $900 for this test by her naturopath. She was referred to us to rule out allergies to the 40 or 50 different foods that were picked up."
"I think it should be the responsibility of the regulators, the government, the laboratories, and the medical people at the laboratories to say, 'You know what? I don't think we should be doing this because it's not scientifically validated and it doesn't seem like the right thing to do."
Dr. Harold Kim, president, Canadian Society of Allergy and Clinical Immunology

"Dynacare relies on the professional expertise of the ordering professional to determine the appropriateness of ordering a particular test."
"While debate exists, there are peer-reviewed articles suggesting there is use for the food IgG test."
Dynacare, Ontario

A study published in 2004 involving 150 people with irritable bowel syndrome found an improvement in symptoms in those who excluded foods to which they had raised IgG antibodies after 12 weeks, while other studies suggest IgG-based 'elimination diets' can relieve migraines and symptoms of Crohn's disease. As far as Dr. Kelso is concerned, he believes that to be a classic placebo effect; people reacting to what they believe will be useful to them.

Dr. Stukus has a more immediate self-help suggestion, that people should themselves eliminate any food they suspect may be the cause of a problem, see if it avoiding it makes any difference, then to reintroduce it to their menu to determine whether the symptoms troubling them return. Simple, effective, no intermediaries required. In a test of his own, Dr. Stukus took home a food sensitivity test, then mailed off his dried blood sample.

To be rather taken aback when the results were returned informing him of sensitivities to sesame, sunflower, black walnuts, cashews, watermelon, yogurt, carrots, cottage cheese, asparagus, tarragon safflower, tomatoes, brewer's yeast, broccoli, chicken, barley, soy beans, baker's yeast, white potatoes, cow's milk, cheddar and mozzarella cheese. "I've never eaten [cottage cheese] in my life", he said disbelievingly.  "It even broke down mozzarella versus cheddar cheese, which is just ridiculous."

Dr. Stukus produced a video and shared it on Twitter, highlighting his experience with the IgG test, meant to identify immunoglobulin G, an antibody that happens to be the most common found in blood and other body fluids. IgG tests make the claim that through its presence they are enabled to identify food sensitivities associated with headaches, lethargy, brain fog, memory problems, depression, insomnia, ADHD, bloating and puffiness -- along with a host of other symptoms.

Such sensitivity tests that are meant to identify 'reactive' food in the diet to relieve people's bothersome symptoms have developed a huge following in the population even while immunology and allergy specialists everywhere consider the test to be no more and no less than a slick marketing gimmick helped along with pseudoscience to convince the gullible. Even so, allergists are seeing an increasing number of patients referred to their offices bringing 'proof' of their problems' origins in the results of IgG food tests.

The entire marketing system surrounding these tests and their legitimacy gets a huge boost from bringing on board celebrities to help market the concept, incorporating the issue that seems to have started the ball rolling; gluten 'intolerance'. Along with it goes the paring away of grains, dairy, meat or shellfish as everyone and her uncle indulges in self-diagnosis as a reflection of a risk-obsessed society. This, despite true food allergies being the cause of a true immune response producing another type of antibody: immunoglobulin E; the reaction occurring swiftly each time the offending food is eaten.

Food sensitivity on the other hand is a term vague enough to draw people in but not commit to a true analysis and diagnosis with scientific accuracy. It is a term beloved of naturopaths and allied alternative medicine practitioners, because it sounds authoritative even while it defines nothing in particular. Food intolerances do exist; there are those who cannot digest certain foods, among the most obvious is lactase intolerance where a lactase deficiency exists leaving the person unable to break down the lactose in milk sugars.

As for gluten disability, it represents an autoimmune disorder damaging to the small intestines, the condition known as celiac disease, where people suffering from it are unable to tolerate even trace amounts of the gluey protein found in wheat, barley and rye and known as gluten. But a mere one percent of Canadians have celiac disease, while over 20 percent of Canadians have taken steps to eliminate or reduce dietary gluten.

Critics of the trendy sweep to laboratory tests for food 'sensitivities' point out the tests are expensive and virtually without merit. Not only do they lack biological plausibility but they run the risk of increasing irregular ideas around eating, producing people who have a hyper-preoccupation with food: "nutrichondriacs". Experts in the field are concerned that IgG testing has the potential to increase anxiety, leading to utterly pointless food avoidance diets, ultimately producing nutritional deficiencies.