Lecture 9. Hunger, Eating, and Health Flashcards
1
Q
a behavior that is of interest to virtually everyone and most of us derive great pleasure from it
A
eating
2
Q
Eating too much is associated with
A
eating-related health problems
3
Q
The average American consumes ___ calories per day, about twice the average daily requirement.
A
3,800
4
Q
motivation to eat
A
hunger
5
Q
main purpose of hunger
A
increase the probability of eating
6
Q
eating’s main purpose:
A
to supply the body with the molecular building blocks and energy it needs to survive and function
7
Q
the gastrointestinal process of breaking down food and absorbing its constituents into the body
A
Digestion
8
Q
Much of the work of breaking down the food we ingest is done by the constituents of our ________
A
gut microbiome
9
Q
process of digestion that breaks up food and mixes it with saliva
A
Chewing
10
Q
process in digestion that lubricates food and begins its digestion.
A
saliva
11
Q
process in digestion that moves food and drink down the esophagus to the stomach.
A
swallowing
12
Q
The primary function of the stomach is
A
to serve as a storage reservoir
13
Q
process in digestion that breaks food down into small particles
A
hydrochloric acid in the stomach
14
Q
during digestion process, this begins the process of breaking down protein molecules to amino acids.
A
pepsin
15
Q
The stomach gradually empties its contents through the ____ into the duodenum
A
pyloric sphincter
16
Q
the upper portion of the intestine, where most of the absorption takes place.
A
duodenum
17
Q
many of them from the gallbladder and pancreas, break down protein molecules to amino acids, and starch and complex sugar molecules to simple sugars
A
Digestive enzymes in the duodenum
18
Q
Fats are emulsified by
A
bile
19
Q
Energy is Delivered to the Body in 3 Forms
A
- lipids
- amino acids
- glucose
20
Q
Energy is Stored In the Body in 3 Forms
A
- fats
- protein
- glycogen
21
Q
the breakdown products of
proteins
A
amino acids
22
Q
a simple sugar that is a breakdown product of complex carbohydrates
A
Glucose
23
Q
preferred mode of energy
storage
A
fats
24
Q
most of the body’s _____ are stored as fats
A
energy reserves
25
chemical changes by which **energy is made available** for an organism's use
energy metabolism
26
3 Phases of Energy Metabolism
* Cephalic Phase
* Absorptive Phase
* Fasting Phase
27
Phase of energy metabolism that **begins with the sight, smell, or even the thought of food**, and it **ends when the food starts to be absorbed** into the bloodstream
cephalic phase
28
period during which the energy **absorbed** into the bloodstream from the meal is **meeting the body's immediate energy needs**
absorptive phase
29
period during which all of the **unstored energy from the previous meal has been** **used** and the **body is withdrawing energy** from its reserves to meet its energy requirements
fasting phase
30
Flow during the 3 Phases is controlled by **2 pancreatic hormones**
* insulin
* glucagon
31
insulin's 3 functions
* promotes the use of **glucose as the primary source of energy** by the body
* promotes the **conversion of bloodborne fuels** that can be stored
* promotes the **storage** of glycogen in liver and muscle, fat in adipose tissue, and proteins in muscle
32
In cephalic and absorptive phase, there is ___ insulin, ___ glucagon
high, low
33
In fasting phase, there is ___ insulin, ___ glucagon
low, high
34
promote the conversion of **glycogen and protein to glucose**
gluconeogenesis
35
high levels of fasting-phase glucagon promote the ____
**release** of free fatty acids from adipose tissue and their use as the body’s primary fuel
36
used by muscles as a **source of energy during the fasting phase**
ketones
37
Theories of Hunger and Eating
Set Points and Positive Incentives
38
Set-point assumption is aka
set-point model or set-point system
39
belief that hunger and eating are normally triggered when the body’s energy resources **fall below** a prescribed optimal level, or **set point**
Set-point assumption
40
3 components of set-point assumption
1. set-point mechanism
2. detector mechanism
3. effector mechanism
41
**defines** the set point
set-point mechanism
42
**detects** deviations from the set point
detector mechanism
43
acts to **eliminate** the deviations
effector mechanism
44
**systems** in which **feedback** from changes in one direction elicit compensatory effects in the opposite directions
Negative Feedback Systems
45
The dominant view in the 1950s was that eating is self-regulated by the interaction between **two set-point systems**:
- a short-term glucostatic system
- a long-term lipostatic system
46
account for meal **initiation and termination**
Glucostatic Theory
47
account for **long-term** regulation and support how body weights of adults stay relatively constant
lipostatic theory
48
determine **when** we eat
glucose levels
49
determine **how much** we eat over long-term
fat stores
50
alternative theoretical perspective
Positive-incentive perspective
51
**anticipated pleasure** of a behavior
positive-incentive value
52
humans and other animals are not normally driven to eat by internal energy deficits but are drawn to eat by the anticipated pleasure of eating
Positive-Incentive Theory
53
Factors that Determine **What** we Eat
1. Learned Taste Preference and Aversions
2. Learning to Eat Vitamins and Minerals
54
Factors that Determine **When** we Eat
1. Premeal Hunger
2. Pavlovian Condition of Hunger
55
Factors that Determine **How much** we Eat
1. Satiety Signals
2. Sham Eating
3. Appetizer Effect and Satiety
4. Serving Sizes and Satiety
5. Social Influences and Satiety
6. Sensory Specific Satiety
56
feeling that **motivates us to stop eating** a meal when there is still food left
satiety
57
satiety signals depend on
both the **volume** and **nutritive density** (calories per unit volume) of the food.
58
Satiety signals, which make us stop eating, can be induced by
food in the gut and glucose in the blood
59
Four observations supporting the view that intention to eat causes the drop in blood glucose
- the rapid timing of the glucose drop
- the persistence of eating without the drop
- the return of blood glucose to normal
when an expected meal isn't served,
- relatively stable glucose levels in the fluid around brain neurons.
60
In the 1950s, research on rats suggested that the hypothalamus controlled eating behavior, with the ____ and ____
* ventromedial hypothalamus (VMH)
* lateral hypothalamus (LH)
61
In the myth of Hypothalamic Hunger and Satiety Centers, this is thought to **regulate satiety**
ventromedial hypothalamus (VMH)
62
In the myth of Hypothalamic Hunger and Satiety Centers, this is thought to **control** **feeding**
lateral hypothalamus (LH)
63
Early experiments found that VMH lesions led to ______
* hyperphagia
* obesity
64
LH lesions caused
- aphagia
- adipsia
65
**excessive** eating
hyperphagia
66
complete **cessation of eating**
aphagia
67
**cessation of drinking**
adipsia
68
Some further research observed that rats with VMH lesions gained weight because of
increased fat production and decreased fat
breakdown, leading to overeating to meet energy needs
69
Some further research observed that rats with LH lesions produced
various
motor disturbances and a lack of
responsiveness to sensory input,
indicating that the LH is not solely responsible for hunger
70
In Modern Research on the Role of Hypothalamic Nuclei in Hunger and Society, Certain neurons in the paraventricular nucleus of the hypothalamus and distinct neuronal populations in the arcuate nucleus have been identified as
nutrient sensors and regulators of metabolism
71
**critical hub** in a neural network that **communicates** with receptors in the blood and gut, suggesting a complex interplay in the regulation of feeding behavior
arcuate nucleus
72
They conducted a pioneering study where one of them swallowed a balloon connected to a tube, and the stomach contractions caused by hunger were recorded
Cannon and Washburn
73
Experiments suggested that the gastrointestinal tract is a source of
satiety signal
74
one of the first gut peptides discovered to **reduce food intake** when injected into hungry rats
Cholecystokinin (CCK)
75
provide information to the brain about the **quantity and nature** of food in the gastrointestinal tract
gut peptides
76
Research on gut peptides and hypothalamic circuits has highlighted the _____
gut's role
77
**monoaminergic neurotransmitter**, has been found to play a role in **metabolism and eating behavior**
Serotonin
78
serotonin-induced satiety
- resistance to highly palatable diets
- a reduction in the amount of food consumed per meal
- a shift in food preferences away from fatty foods
79
a condition associated with **excessive** hunger and overeating
Prader-Willi Syndrome
80
prader-willi syndrome is characterized by
- weak muscles
- small hands and feet
- feeding problems in infancy behavioral issues like tantrums and compulsive behavior as well as skin
picking.
81
aim to **preven**t significant weight changes in adults
Set-point mechanisms
82
Set-point theories suggest each person's set point is
optimal for their health
83
Caloric restriction can have positive effects on neurological conditions such as
- reducing seizures
- improving memory
84
The body controls its fat levels largely by
changing energy efficiency
85
As body fat decreases, energy usage becomes
more efficient, limiting further weight loss
86
weight gain leads to
decreased energy efficiency
87
is the mechanism behind energy efficiency adjustments based on
body fat levels.
Diet-induced thermogenesis
88
proposes that body weight naturally **settles** around an equilibrium influenced by various factors
settling point model
89
used to **illustrate** the settling-point mechanism
Leaky-barrel analogy
90
Causes of overeating
- evolutionary perspective
- cultural practices and beliefs
- parental influence
- modern environment
91
factors if why do some people gain weight from overeating while others do not?
1) differences in energy expenditure
2) differences in gut microbiome composition
3) genetic and epigenetic factors
92
4 differences in energy expenditure
- exercise
- basal metabolic rate
- diet-induced thermogenesis
- non-exercise activity thermogenesis (NEAT)
93
The gut microbiome outnumbers our own
bodily cells by
10 to 1
94
4 factors of ineffective weight loss programs
- typical weight loss programs
- difficulty of permanent lifestyle change
- efficiency of the body
- compensatory eating
95
a peptide hormone **released from adipose tissue** and **encoded by the obese (ob) gene**
leptin
96
treatment of overeating and high body-fat levels
- serotonergic agonists
- gastric Bypass Surgery
97
potential to **reduce** **food consumption** in both humans and animals, **enhance** **short-term satiety signals** associated with meal consumption and can **reduce various overeating-related factors**
serotonergic agonists
98
examples of serotonergic agonists
- fenfluramine and dexfenfluramine
- lorcaserin
99
a **surgical** treatment for those who are extremely overweight that involves short-circuiting the normal path of food through the digestive tract
gastric bypass surgery
100
involves surgically positioning a **hollow silicone band** around the stomach to reduce the flow of food through it.
Adjustable Gastric Band Procedure
101
characterized by a **refusal to eat enough** to maintain a healthy body weight
anorexia nervosa
102
characterized by periods of not eating interrupted by **bingeing** followed by efforts to immediately eliminate the consumed calories from the body by purging
bulimia nervosa
