In the book, The Omnivore's Dilemma, what does "dilemma" refer to?

The Omnivore's Dilemma,by Michael Pollan, is about the evolution of food culture and how the history and biology of humans has come to shape the way we eat today. One of the main themes of the book is a focus on taste- Pollan describes humans as "generalists" when it comes to food. Some species of animals, including our closest primate relatives, are "specialists," eating only a limited number of foods. Humans, on the other...

The Omnivore's Dilemma, by Michael Pollan, is about the evolution of food culture and how the history and biology of humans has come to shape the way we eat today. One of the main themes of the book is a focus on taste- Pollan describes humans as "generalists" when it comes to food. Some species of animals, including our closest primate relatives, are "specialists," eating only a limited number of foods. Humans, on the other hand, eat a wide variety of both plant and animal foods- even some things which can have negative effects on our bodies! For example, many people like to eat spicy food, even though it makes their mouth burn. The endorphin rush of eating spicy food creates a sense of pleasure, and some people may see eating spicy foods like chili peppers as a challenge to be overcome proudly. 

So, when humans consider such a wide variety of foods to be edible, how do we decide what to eat? This is the dilemma, or problem, Pollan is referring to. One way to answer this question is by the fact that many foods are eliminated from a person's diet by a lack of access. If a person lives in an area where certain foods cannot be grown or transported before spoiling, this food is not typically considered when it comes time to decide what to eat. Pollan argues that we primarily decide what to eat based on taste. Our taste buds are evolutionarily hardwired to prefer certain kinds of foods- namely sugar and fat. Sugars and fats are great sources of energy, and the pleasure of taste encourages us to eat more of these foods. 

Pollan talks about the human taste preference for sweet and fatty foods in relation to the global obesity epidemic. Many commercially produced food products, and especially fast foods, are "designed" to exploit the taste preferences humans have evolved through a long struggle between nature and nutrition. Such intentional creation of foods can create an addiction to these powerful sources of flavor, with some sacrifice of actual nutritional value. Whereas the human preference for sugar developed in response to eating fruits (which have a high vitamin content,) this taste preference is exploited by drinking soda-pop or other sugary beverages. Soda-pop offers a sweet taste and a rush of pleasure for the drinker, but very little nutritional content beyond calories. This presents the second dilemma: are humans really able to choose what to eat when many of the foods we love have been specifically designed to exploit our taste preferences?