On Food Allergies and Intolerances

Individuals may experience allergies to any number of substances, but reports indicate that a growing number of Americans suffer from allergies to particular foods. Food allergies affect approximately 12 million Americans, including three million children. ”Food intolerances,” though frequently discussed in conjunction with food allergies, are quite different. Individuals with “intolerance” to certain foods may experience adverse reactions and discomfort if they are consumed. It is important to have an understanding not only of the severity and potential risk of food allergies, but of the difference between true allergies and intolerances.

The majority of adverse reactions linked to particular foods are due food intolerances. Individuals can be intolerant to lactose, gluten, or other foods, and may experience nausea, vomiting, stomach cramping, and diarrhea. While these symptoms are surely unpleasant, they are markedly different from the immune response seen in individuals with food allergies. In addition to bowel discomfort, food allergies can cause an anaphylactic response, leading to tingling and swelling of the mouth and face, hives, trouble breathing, dizziness, or fainting. These symptoms are caused by an response in which the body’s immune system mistakenly identifies a particular food as a harmful substance. An allergic reaction involves two components of the immune system: an antibody called immunoglobulin E (IgE), and a mast cell. When an individual consumes - or in some cases is in close contact with - a food to which they have an allergy, the allergen stimulates specialized white blood cells called lymphocytes which produce the IgE antibody for that specific allergen. This IgE is then released and attaches to the surface of the mast cells in the tissues of the body, prompting the cells to release histamine.

Allergic reactions can range in severity, but reports indicate that they cause 30,000 cases of anaphylaxis, 2,000 hospitalizations, and 150 deaths each year in the United States. According to the U.S. Centers for Disease Control and Prevention (CDC), there are eight foods which account for 90 percent for all food-allergy reactions: cow’s milk, eggs, peanuts, tree nuts (walnuts, pecans, etc.), fish, shellfish, soybeans, and wheat. One of the most common food allergies in the United States is to peanuts, affecting an estimated 3.3 million Americans. The incidence of peanut allergies is increasing, and reports indicate that between 1997 and 2008, the rate of child peanut allergies has tripled. Rates of other food allergies have also increased in recent years, and according to the CDC, the number of children with food allergies increased by 18 percent, between 1997 and 2007. While the cause of the increase is not fully understood, it may be due in part to the risk factors associated with food allergies, which include a family history of asthma and allergies, and elevated IgE levels.

Though there is no proven treatment for food allergies other than the avoidance of the allergen, experts recommend that individuals with food allergies carry injectable epinephrine at all times, as it can help to mitigate severity of the allergic response. In addition to the physical health-related issues resulting from food allergies, reports indicate that more than 30 percent of children with food allergies have experienced teasing or bullying related to their allergy. By gaining an understanding of food allergies and sharing information about them with others, it may be possible ensure that individuals are better informed about how to help prevent allergic reactions, and lessen the stigma faced by children with food allergies.

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On Alzheimer's Disease

Dementia is not a specific disease, but rather a group of symptoms affecting intellectual and social functioning. The most common form is a progressive form of presenile dementia first identified in 1906 by Dr. Alois Alzheimer, known as Alzheimer’s disease. Experts indicate that the number of individuals with Alzheimer’s worldwide could increase from 35.6 million to 65.7 million by 2030, due in part to the growth in aging populations. Additional reports indicate that in the U.S. alone there are currently 5.3 million people living with the disease, and this figure is projected to increase to 16 million by 2050. While there is no cure for Alzheimer’s disease, through treatment and education, it may be possible to improve outcomes for those with the condition.

Accounting for 50 to 80 percent of dementia cases, Alzheimer’s disease is marked by the loss of intellectual and social abilities severe enough to interfere with an individual’s daily functioning. As it progresses, Alzheimer’s disease may lead to mood swings, distrust of others, social withdrawal, and depression. Though it is not a “normal” part of the aging process, the risk of developing Alzheimer’s disease increases with age. Approximately five percent of people between the ages of 65 and 74, and nearly half of those over the age of 85 have Alzheimer’s disease. Although there is no known direct cause for the disease or means to ensure its prevention, research suggests that there may be a genetic link to the development of Alzheimer’s, and that lifestyle choices like maintaining a healthy weight and exercising one’s body and mind can at least delay the onset of the condition.

Alzheimer’s disease is most often diagnosed using a combination of blood or spinal fluid tests to rule out other possible causes of dementia, and brain scans to locate any visible abnormalities. Though doctors can accurately diagnose 90 percent of Alzheimer’s patients, the condition can only be diagnosed with complete accuracy during an autopsy. A post-mortem microscopic examination of the tissues of the brain of individuals with Alzheimer’s, reveals two abnormal structures called “Plaques” and “Tangles,” which are damaging to nerve cells. Plaques contain deposits of a protein fragment called beta-amyloid and build up between nerve cells, while twisted fibers of tau protein known as Tangles form inside dying cells. Though researchers do not yet have a full understanding of the role that Plaques and Tangles play in the progression of Alzheimer’s disease, experts believe that they block the communication among nerve cells and disrupt cell activities. Recent research has shown that Tangles may offer some insight into how quickly Alzheimer’s disease will progress in an individual, leading to the development of potentially tau-lowering drug treatments.

New research suggests that large doses of vitamin B may halve the rate of brain shrinkage in individuals with mild cognitive impairment. Though the mechanism by which B vitamins slow the progression of Alzheimer’s has not been identified, some B vitamins have been shown to control levels of homocystieine, an amino acid associated with an increased risk of Alzheimer’s. These new treatments, as well as the medications commonly used to help improve some of the symptoms of Alzheimer’s, which include cholinesterase inhibitors and memantine can help to improve the lives of individuals with Alzheimer’s. On average, these live half as long as a peer who does not have the disease – meaning that a 75-year-old diagnosed with Alzheimer’s can expect to live another six years, while a 75-year-old without the condition may live 12 years. However, because of the variance in the severity of cases and the speed with which symptoms progress, the life-expectancy of individuals with Alzheimer’s varies greatly.

Further research related to testing, diagnostic, and treatment procedures may lead to improved outcomes for individuals with Alzheimer’s. By gaining a better understanding of this condition and its causes, it may be possible to slow or halt its progression and improve the lives of millions of elderly individuals worldwide.

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