Food allergy and intolerances 食物過敏與不耐性

1. What are the differences between allergy and intolerances ?The term allergy was first coined by Austrian pediatrician Clemens von Pirquet who put together two Greek words, allo (other) and ergon (work or action). An allergic person reacts to substances that don't bother other people. Our immune system defends us against unseen enemies such as bacteria and viruses, but sometimes has difficulty in distinguishing friend from enemy and may overreact to a totally harmless substance like egg, strawberry as in food; grass pollen as in air, causing sudden reactions ranging from rashes, swollen lips...... to the very extreme life threatening one called anaphylactic shock causing by peanut. This is an example of immediate type allergy where specific antibodies have developed in the blood and tests can be useful in identifying the specific allergens. This type of immediate allergy affects smaller number of people. Another type of "allergy" is a delayed reaction which may occur several hours or days after exposure or ingestion. They are called "intolerances" and food intolerances are quite common. It is when you develop symptoms after eating a food that the digestive system cannot adequately process. The symptoms will be less severe and serious, but they can undermine health and well-being. A food intolerance often tends to be to the foods we most commonly eat. In fact, we may find we crave the foods that we are intolerant to. 2. What causes allergy and why there seems to be an "allergy epidemic"?Many believe that the genetic profile of a person plays an important role in determining whether he or she may have allergy. It is indeed true that a child with a parent having asthma has a higher chance of getting asthma and the same applies to other common types of allergies such as eczema. We always hear from people that allergies run in families. Another explanation is the rapid introduction of various new chemicals to the environment and the changes which have taken place in the diet over the last hundred years which are the culprits responsible for provoking symptoms of allergy or intolerance, especially in susceptible persons who are genetically more vulnerable. Adaptation to change in the environment is the force that has driven the evolution of all species throughout the ages, and it is supposed to be gradual and slow. Rapid introduction of a new food and contamination of our environment by new chemicals may not give sufficient time for adaptation to occur, resulting in a dramatic rise in allergy and intolerance.
3. Despite the common incidence of allergy,why allergy does not seem to receive much attention in mainstream medicine?Adaptation of our body to environmental changes requires an efficient functioning of our body system. Imagine our body is a textile factory with different machines (such as immune system, endocrine system, nervous system, circulatory system......). All these specialized machines (systems) work as a team and our body can only be maintained in a stable state by the complex interplay of these body systems. Complete failure of an essential system may lead to death and partial failure may lead to specific illness in certain parts of the body system which can be suppressed by modern medication. Advances in knowledge of how these body systems function has inevitably resulted in increasing specialization, which unfortunately has also tended to create boundaries between specialties. Allergy is usually linked to the failure of our immune system but the symptoms may manifest from fatigue, rashes, weepy eyes, respiratory problems to significant mood swing, depression......Modern medicine tended to look at symptoms occurred in a particular system and allergy is regarded as trivial and psychological. There is increased belief that not until accurate diagnosis of the causes, avoidances and immunotherapy of a childhood allergy/intolerance are taken more seriously, the rise in allergy will continue.
1. 食物過敏與不耐性有甚麼分別 ?過敏(Allergy)這個詞最先由奧地利的小兒科醫生Clemens von Pirquet發明，他將兩個希臘字allo(其他)和ergon(工作或行動)湊併而成。過敏患者對某些其他人沒有反應的物質過敏。我們的免疫系統保護我們免受一些看不到的敵人侵害，好像細菌和病毒，但有時卻敵友不分，對無害的物質例如食物中的蛋、草莓、空氣中的花粉等反應過激，出現突發性的不同程度的過敏反應，好像紅疹、唇腫…甚至由花生引致的過敏休克更會足以致命。這是某種抗體在血液中產生而引起的立刻性過敏的例子，通過測試可分辨出相關的過敏原。甚少人會有這種立刻性過敏症。另一類是產生慢性反應的過敏，可以在接觸或進食致敏原後的數小時以至數天才出現。它應被稱為「不耐性」，而食物不耐性其實是十分普遍的情況。這是因為你進食了一些自身消化系統無法正常處理的食物而出現的症狀。它引發的病徵不會很嚴重，但會損害身體和精神上的健康。引致食物不耐性的食物通常都是那些我們經常進食的食物。實際上，你會發現那些會令我們產生不耐性的食物，通常都是我們渴望的食物。2. 是甚麼引致過敏，為何現時好像出現了「過敏症疫潮」?很多人相信一個人的遺傳基因是決定他會否患上過敏症的重要因素。要是小孩的父母有哮喘病，他亦真的有較大機會患上哮喘，同一道理亦適用於其他類型的過敏症好像濕疹等，所以我們經常會聽到有人說一家人都有過敏症。另一個可能性原因是，近年在我們的周圍出現了各種日新月異的化學品，而我們的飲食模式在過去一百年來亦出現了不少變化，這些因素都是誘發過敏症和不耐性的原凶，尤其對那些擁有遺傳基因不利因素的人們，其影響更甚。適應環境是自古以來促成所有物種不斷演化的力量，但改變應該是緩慢和循序漸進的。急速地引入新食物，以新發明的化學品去污染環境，未能讓我們有足夠的時間去適應，故此造過敏和不耐性急劇增加。3. 儘管過敏症非常普遍，為甚麼主流醫學似乎對它不大關注?我們需要有效的身體功能運作才能適應環境的改變。試想如果我們的身體是一家紡織廠，內裏有不同的機器(例如：免疫系統、內分泌系統、神經系統、循環系統… 等)。所有這些特別的機器(系統)都要合作無間，而我們的身體只能在這些身體系統相互穩定地操作的情況下，始能保持良好的狀態。假如一個重要系統完全無法運作便令我們死亡，即使只是部份失靈亦會令我們患上某種疾病，須賴現代醫藥去抑制這些疾病。預知這些人體功能系統如何運作在醫學上衍生出不同專業的醫學範圍，不幸地這亦造成了醫學專業間的鴻溝。過敏症通常與免疫系統有關，但它表現出來的病徵卻是疲倦、紅疹、流眼水、呼吸系統問題，以至情緒波動和抑鬱…等。現代醫學傾向於診治病徵出現的部位而認為過敏是無關重要和心理因素所致。但愈來愈多人相信，如果不正視兒童過敏症/不耐症的源頭、致敏原和採取免疫療法，過敏症的上升趨勢只會持續上升。