Eating behaviour

• The evolutionary explanation for food preferences

  Argument that any common food preferences exist are because they provide an adaptive advantage

  There are three different preferences; sweetness, salt, fat
• Preference for sweetness

  Food preferences are linked to sweet taste as it is a reliable source of high-energy food

  Steiner (1977) placed sugar onto the tongues of new-borns and found positive facial expressions, new-borns can even distinguish between different sugars

  Fructose is a 'fast-acting' sugar which provides energy quickly and babies will consume large amounts of it if allowed

  It is present in ripe fruits which would have been a favoured food from our distant ancestors
• Preference for salt

  A salt preference appears in humans at about 4 months

  Harris et al (1990) found that babies between 16 & 25 weeks who had been breastfed preferred salted rather than unsalted cereal

  Breast milk is low in salt so this suggest that they had not learned a salt preference but it is innate
• Preference for fat

  High-calorie foods were not readily available to our evolutionary ancestors so they learned to prefer food which were high in calories which provide energy that is essential for survival

  Fat contains twice as many calories as the equivalent protein or carbs making it the most efficient route to ensuring high calorie energy food consumption
• Neophobia

  Humans have the innate unwillingness to eat new or unfamiliar foods

  It is most pronounced in childhood between the ages of 2 and 6

  Birch (1999) suggests it appears at a time when children begin to explore their environments and may encounter foods independently of their parents guidance as to what is safe

  Untried foods could be dangerous, co neophobia is adaptive so we don't eat things which could be fatal or make us ill

  Reduces us to learn the reality of what will harm us and what will not
• Taste aversion

  Seligman's (1971) theory of biological preparedness. We acquire certain taste aversions of fears more quickly that others

  certain things that posed most threat to our ancestors

  We are genetically hardwired to learn taste aversions

  less likely to eat food that has gone bad

  Garcia & Koelling (1966) classically conditioned rats to acquire taste aversion to sweetened water after pairing it with poison. Less successful when pairing the water with electric shock. A taste eversion is likely to be the outcome of eating poisoned food

  It os an adaptive response that aids survival
• Evolutionary explanation evaluation (strength)

  Supported by research studies

  Torres et al (2008) reviewed relevant studies into the kink between stress and eating behaviour

  They concluded that human tend to eat high-fat foods during periods of stress
• Evolutionary explanation evaluation (limitation)

  Neophobia is no longer adaptive for the modern environment

  Most food consumed is sold by retailers and have strict laws meaning the food is safer and little threat to survival

  It now prevents us from eating safe foods at a young age and restricts a child’s diet
• Evolutionary explanation evaluation (limitation)

  There is individual differences in food preferences

  Drewnowski et al (2001) found that people differ in their ability to detect PROP, PROP insensitivity appears to be an inherited trait

  Counterpoint

  However there’s evidence that links PROP insensitivity with other traits that may have helped with different survival benifits