Textbook Notes (280,000)
CA (160,000)
U of G (10,000)
PSYC (3,000)
Chapter 7

PSYC 3110 Chapter Notes - Chapter 7: Alcoholism, Greenhouse Gas, Gastric Bypass Surgery


Department
Psychology
Course Code
PSYC 3110
Professor
Kieran O' Doherty
Chapter
7

Page:
of 15
Chapter 7: Food Eating and Environment
Page: 142-156, 161- 164
Eating and Obesity
Eating and drinking are social activities that incorporate symbolic, moral and
cultural meanings
Obesity: an excessive accumulation of body fat, usually defined as a body mass
index greater than 30
Eating preferences and habits based on conditioning, customs and culture and
environment (climate change)
Surgeon General “obesity is the fastest growing cause of disease and death in
America”
Risen over 30 years
o 37% (overweight children and adolescence) and 34% (risk of being
overweight)
multiple causes
o genetic predisposing
o culture
o diet
o in activities
foods industry uses several strategies to maintain their profits
o persuading to consume more food, especially high energy dense foods
through advertising and outlets
o increasing serving sizes, price inducements to order larger sizes
o opening markets in transitional and developing countries
o substituting agricultural products with efficient artificial foods (margarine
for butter)
o adding sugar, salts, fats, oils and dyes to enhance flavour, look
explanation
o Less active
o Income (mcdonalds because its cheap)
o Stress- high stress associated with more fatty food intake, less fruits and
veggies, no breakfast
Linking eating habits to climate change
o Earth is becoming warmer due to Greenhouse Gas (GHG) emissions into
atmosphere
Biological Influences on Body Fat level
o Sex
o Hormonal factors
o genetics
o fat gene: MC4R: alleged to play a role in regulating food intake and
energy balance
associated with higher intakes of total energy, dietary fat, greater
long term weight change, diabetes in women
Evolutionary perspective
began with hunting and killing for food with weapons and tools fashioned from
pieces of volcanic obsidian
genetic make up of contemporary humans remains adapted to a nomadic
existence of gathering and hunting
humans are hunter gathers: not fitted to lifestyle and forms of social
organization that exsit in todays post agricultural, post industrial societies
Hunter Gatherers past and present
lived in bands of 10-50 people with an average band size of 25
temporary shelters near water, food and supplies
settled for months at a time
early hunter gatherers spent less time building shelters and obataining food that
most humans after the agricultural revolution
75% of food energy from vegetables 25% hunting animals
energy expenditure: use by body of chemical energy from food and drink or body
stores during the processes of metabolism that is dissipated as heat; days total
energy expenditure is measured in calories of heat lost
o average daily EE for 65kg male is 3.5 megajoules compared to 4.4 of
hunters
huntin and fishing done by men
grinding grain and fetching water done by women
reduction in energy expenditure in women may have exceeded that of men;
consistent of observations that obesity is generally more common in women
then men
natural ecosystems provide a diet of wild foods that is varied and plentiful
protein, mineral and vitamin intake among hunter gatherers would have been
above recommended level
capacity to store fat easily was important for survival
less food during winter so ice age hunter gatherers needed to store fat to survive
high energy intake is a risk factor for obesity in humans
low resting metabolic rate is a risk factor for weight gain
Leptin: a hormone produced by adipose cells that inhibits food intake and
increases energy expenditure
Relatively low plasma leptin concentrations may play a role in development of
obesity in pima Indians (based off study)
Agricultural Revolution
Humans lived for the first time in densly populated villages and towns
Sheeps and goats kept in captivity to provide ready of supply of meat
Spread through Europe
Stabilizing influence of settlement and civilization came consequences
o Food supplies were more dependent on weather conditions
o Diet became less varied and balanced
o Malnourished, anaemia and osteoporosis became prevelant
o Levels of activity nd energy expenditure decreased
o Bowel and respiratory infections increased
o Birth rate increased
o Social problems related to population density and ownership became
prevelant
o Psychological and socio economic stress related to population density,
property, status and self esteem became significant
Industrial Revolution
Life styles changed drastically (electricity, transportation)
Food is now ready in supermarkets (no longer need manual labour)
Ecological Model
Adiposity: the fat content of the body, fat content of foods and relationship
between the two
Ecological systems theory of Bronfenbrenner
o Individual childs genertic environment
o Family environment
o Larger community
o Ecological approach shows the necessity of community scale
interventions in addition to an approach based on individuals will power
to change their behaviour
Fat and Feeling Fat
o Two main subjects of obesity: high fat foods and overweight people
o Most western countries proportion of food energy derived from fat is
close to 40%
o Triglyceride: the main component of dietary fats and oils and the
principal form in which fat is stored in the body
Composed of three fatty acids attached to a glycerol molecule
Saturated (S)
Monounsaturated (M)
Polyunsaturated (P)
o Cholesterol has been implicated as a casual factor in coronary heart
disease
o Low density lipoprotein (LDL): bad cholesterol, associated with heart
disease
o High density lipoprotein (HDL): good cholesterol
o Hypercholesterolemia: high level of bad cholesterol in the blood, risk of
heart disease
o Adipose tissue: tissue in the body in which fat is stored as an energy
reserve and which in excess leads to obesity
Toxic environment