Translation: This person cannot digest gluten, a protein found in wheat, rye and barley. Untreated, the disease can damage the small intestine, interfering with the body’s ability to absorb nutrients. This can lead to anemia and osteoporosis. There’s a genetic component to the disorder. The only effective treatment is a gluten-free diet for life. Odds: 1 in 133 people, suggest NIH stats. Also consider: Your guest also must avoid rye and barley. Even trace amounts of gluten can cause health problems, so when using packaged products look not only for wheat-free foods but also a “gluten-free” label. Learn more: celiac.org.
Translation: This person chooses not to eat (or use) animal-derived products or products tested on animals. Odds: 1 in 72 people. A 2006 poll conducted by the Vegetarian Resource Group found that 1.4 percent of American adults consider themselves vegan. Also consider: Vegan diets exclude all foods of animal origin, including meats, poultry, dairy and gelatin (some avoid honey too). Learn more: vegan.org.