food preferences

evolutionary explanations

  • neophobia - innate fear of new or unfamiliar foods. adaptive as it would help avoid potentially harmful foods, aiding survival

  • taste aversions - dislike of a food after a negative experience with it. biological preparedness proposed by Seligman suggests that were biologically hardwired to develop a dislike for foods after trying it once to avoid illness and harm

  • steiner 1979 observed found that babies reacted negatively when tasting bitter foods and positively with sweet foods, suggesting that food preferences are innate

learning explanations

  • family influence - watching your parents eat certain foods informs you about your own eating behaviour. because they are often seen as role models, you are more likely to observe and imitate them. the positive outcome of eating those foods acts as vicarious reinforcement which encourages you to eat the food they eat. this helps reduce neophobia. operant conditioning - rewarding kids when they eat healthy foods, punishing when they don't, could decrease preference for food they don't like.

  • media influence - tv ads promote unhealthy foods which promotes unhealthy eating in kids, hare braun found that kids who watched tv more ate more unhealthy foods but after 6 years, this link weakened and disappeared in girls which suggests that peer influence is a greater influence after a certain point.

  • cultural influence - lack of access/availability of foods in some countries can cause the development of food preferences in people. for example, coastal areas eat more seafood that continental areas. furthermore, some countries eat foods that others may not. for example, escargot in france. traditions like this could mean that people within certain cultures become used to their cultural foods and form food preferences.

  • religion can also influence food preferences because certain religions are restrictive when it comes to certain foods. in islam and judaism pork is not allowed and in hinduism beef is not allowed. practices such as these means that people of that group start to develop preferences within their religious boundaries.

  • increasing globalisation means different countries have access to different cultural foods. for example, the increase of immigration in london has meant that there is more varied food options such as chinese and caribbean food. people also spend money on eating out more so peoples food preferences could change as a result of having more access to different foods.

neural mechanisms

  • hunger is controlled in the hypothalamus

  • lateral hypothalamus - ‘on switch’

    • when blood glucose is low, the liver sends signals to the LH which stimulates feelings of hunger by releasing neuropeptide Y and causes the person to eat

  • ventromedial hypothalamus - ‘off switch’

    • when blood glucose is high, the VMH will sends signals and stimulate feelings of satiety and stop eating

  • dual centre model - regulating hunger

hormonal mechanisms

  • ghrelin - released from the stomach when it is empty, hormonal marker of when the person last ate

    • the emptier the stomach, the more released

    • detected by the arcuate nucleus and stimulates the LH to release neuropeptide Y

    • when given intravenously, it can cause short term increase in food eaten (Malik 2009)

  • leptin - released from adipose cells to signal that calorie storage is high

    • VMH detects release of leptin and increase feelings of satiety so the person stops eating

    • leptin inhibits by

      • reducing ghrelin secretion

      • suppressing expression of ghrelin receptors in neuropeptide Y system