CHAPTER 10
Small Changes, Big Trouble
PART 1
Protein Allergies
Given the astounding number of molecular processes involved in digesting, metabolizing, and building protein, it’s remarkable how seldom things go wrong. But errors and issues can arise in the midst of any protein-related activity, whether digestive enzymes are missing or amino acids are incorrectly aligned as they’re being strung together to build a new protein within a ribosome. Such protein problems are known to be, or believed to be, at the root of several conditions. READ MORE
Allergies
Every allergic reaction is rooted in an adverse response to a protein. According to the American Academy of Allergy, Asthma & Immunology, allergies of every kind —food allergies, contact allergies, insect allergies, allergies to airborne substances such as pollen — are steadily increasing in prevalence.
We know allergic reactions are caused by a hyperactive response of the immune system. Though a protein within food or tree pollen may in and of itself be harmless, in the allergic person the immune system mistakenly identifies the protein (an allergen) as dangerous and goes on the attack. Researchers understand the mechanics of immune response — but are not yet clear on why the system errs in the first place. LESS
PART 2
Milk Allergy and Lactose Intolerance
There are a number of proteins in milk that can cause allergic reactions. The dominant proteins in cow’s milk are caseins and whey. In susceptible individuals, one or more of the proteins can prompt an immune response. This is known as milk-protein allergy. The immune system reaction can cause any number of symptoms including digestive issues and/or classic allergy symptoms such as wheezing and rash. READ MORE
However, milk-protein allergy should not be confused with the more common problem of lactose intolerance, the hallmarks of which are cramping and general digestive unpleasantness following the consumption of a dairy product. In this case the offender is not protein in the food; rather it is the lack of a specific protein in the gut that is to blame.
Lactose is a sugar found in milk and other dairy products. The enzyme lactase, which is a type of protein, is responsible for splitting lactose into its component sugars (glucose and galactose) and enabling them to be absorbed. But when supplies of lactase are deficient (inadequate “expression” of the lactase protein, in scientific parlance), the undigested lactose descends toward the colon where it is fermented, causing digestive issues. There’s no treatment or resolution other than limiting dairy intake, although tolerance varies and some can use yogurts, aged cheeses and even a small amount of milk. Using lactose-reduced products and lactase supplements can be helpful. We haven’t yet learned how to boost lactase production. LESS
PART 3
Protein Defects Yield Disease
The Tau of Alzheimer’sIn 1906, when Alois Alzheimer and two colleagues autopsied the brain of a patient who had suffered from dementia, they discovered the amyloid plaques and neurofibril tangles that still characterize Alzheimer’s disease. Nearly a century later it was recognized that the plaque, itself made of protein, wreaks neurological havoc by preventing other proteins from traveling through brain cells — thus starving the cells of energy. READ MORE
Late in 2010, a team of Swedish researchers discovered that another type of protein — tau protein, abundant in the central nervous system’s neurons — builds up in the Alzheimer brain well before amyloid plaques form. When tau protein molecules are defective, they accumulate in clumps within brain cells and prevent messages from being sent across a synapse from one neuron to another.
Celiac Disease
The call for “gluten-free” food was sounded primarily to combat celiac disease. The condition, marked by an inability to absorb nutrients, effects less than 1% of the population but has changed the way many grain-based products are manufactured and marketed.
Foods such as breads and pasta made with wheat, barley or rye contain the protein gluten. Latin for glue, the protein lends a workable elasticity to raw dough, and body to a cooked bread or pasta. But some people have an allergic reaction to gluten. Due to an inflammatory immune response, the villi (tiny projections) lining the intestines are truncated and cannot perform the job of absorbing essential vitamins and minerals. The only known treatment is to pursue a very low-gluten or gluten-free diet.
Phenylketonuria (PKU)
Traced to a genetic birth defect, phenylketonuria is a condition in which an enzyme (protein) needed to break down phenylalanine is not produced. Phenylalanine is an amino acid found in many high-protein foods, including milk and cheese, meats, and nuts.
Though the body needs phenylalanine, too much accumulates in a person who lacks the enzyme to metabolize it. In an untreated newborn, PKU can lead to irreversible brain damage. Older children may suffer seizures and behavioral problems. Parents of kids with PKU must examine and regulate the child’s diet down to every ingredient. When you see a diet soda can or other label reading Contains phenylalanine, that’s a warning for people with PKU. LESS