NUTR 2105 Lecture Notes - Lecture 16: American Medical Association, Ventromedial Nucleus Of The Hypothalamus, Peptide Yy
1 May 2018
School
Department
Course
Professor
Why is Weight Management Important?
Weight management is maintaining body weight w/in a healthy range
(18.5 to 24.9)
○
Healthy weight is a body weight that does not incr. risk for developing
weight-related health problems or diseases
○
Healthy weight lowers risk for chronic disease
○
-
AMA Considers Obesity a Disease
In 2013, American Medical Association declared obesity a "disease"
○
Benefits to declaring it a disease
Provides a clear warning of health hazards of being overweight
§
May make it easier for individuals to get insurance coverage for
treatment
§
More research funding may ne allocated to addressing the obesity
problem in the U.S.
§
○
Downsides to declaring it a disease
It may encourage more use of drugs and medicals procedures to
address the epidemic rather than encouraging lifestyle changes
§
Cost treating obesity will skyrocket
§
○
-
Being Overweight or Underweight Carries Social and Psychological Risks
Overweight people are treated differently from people at a normal weight
Suffer more discrimination
§
More likely to be denied job promotions and raises
§
Obese females are less likely to be accepted into college, esp higher
ranked colleges
§
○
Obese people have higher rates of suicide and are more likely to use
drugs and alcohol
○
Individuals who are underweight are more likely to be at greater risk for:
○
-
How is Food Regulated?
Appetite is the desire to eat food whether or not there is physical hunger
○
Hunger and satiety affect the desire to eat and to stop eating
○
The brain and hormones control feeding
○
Satiety is triggered by the ventromedial nucleus (part of hypothalamus,
which controls hunger/ fullness)
Cholecystokinin (CCK) and peptide YY (PYY)
Secreted by the small intestine to stimulate satiety□
§
Leptin
Produced in adipose tissue (fat tissue)□
Decreases hunger and food intake□
Regulate amount of fat stored□
Decreased w/weight loss and intake of certain vitamins and
minerals (zinc supplements, low vitamins C and A)
□
Get to a certain point where you body doesn't respond□
§
○
Certain macronutriens, esp protein, promote satiety and reduce food
intake
○
Hunger is controlled by lateral hypothalamus
Ghrelin
§
Neuropeptide Y
§
Leptin
§
○
-
How do Fat Cells Form and Expand?
Growth of fat cells (adipocytes) occurs in 2 ways
Can expand to store more fat (hypertrophy)
§
Once filled to capacity, stimulate the production of more fat cells
(hyperplasia)
§
○
The # of Fat Cells in the Body Never Decreases
Average adult has 30 to 50 billion adipocytes, which hold 0.4 to 0.5
micrograms of fat each
§
○
Fat Cells can Grow and Shrink
Enzymes control the size of fat cells
§
Heavier people have increased LPL activity
§
○
-
How Do Genetics and Environment Influence Obesity and Weight Management?
Nutrigenomics and epigenetics may influence weight control
Nutrigenomics:
§
Epigenetics:
§
Food and nutrients are a factor that can activate or repress certain
genes
§
○
Genetics can Influence Hunger, Satiety, and Insulin Response
Altered genes may determine an individual's hormonal response in
the presence of food, affecting hunger and satiety
§
Multiple genes receive signals that change their structure, which
then turns them on or off
§
Genes can be turned on or off by a combo of DNA methylation and
histone modifications
§
Genes are transcribed through transcription factors that are
activated by cellular signaling cascades
§
Adipocytes secrete the hormone adiponectin
Improves the body's response to insulin□
§
Some individuals store more fat w/ excess energy intake
§
Genes may cause different rate of thermogenesis
§
Genetic "set point" theory
§
Populations which are genetically prone to being overweight or
obese can overcome their genetic predisposition by engaging in
regular exercise and eating healthy
§
○
Environmental Factors can Increase Appetite and Decrease Physical
Activity
Our current environment makes it easier to have positive energy
balance and gain weight
§
Environmental factors involved w/ obesity
Lack of time□
§
An abundant food supply and portion distortion
§
Lack of physical activity and increased sedentary behavior
People do less manual labor in their jobs□
The more people drive, the less they engage in physical
activity
□
More time is spent in front of the TV or computer□
§
○
-
How Can You Lose Weight Healthfully?
Strive for a reasonable rate of weight loss
Lose 10% of body weight over 6 months
§
Modify diet, physical activity, and behavior
§
○
Remember that kcals count
Choose lower kcal foods
§
Reduce portion sizes
§
Increases kcals burned
§
○
Eat more vegetables, fruit, and fiber
○
Avoid mindless eating
○
Adding volume to meals
○
Adding some protein and fat to meals
Protein promotes satiety
Focus on lean protein□
§
Fat slows movement out of the stomach
Focus on healthy fats in moderation□
Limit fats high in saturated-fats□
§
○
Use MyPlate as a weight-loss guide
○
Increase physical activity to lose weight
Increases kcals burned and displaces sedentary activity
§
60 to 90 minutes daily of moderate-intensity physical activity to aid
in weight loss, prevent weight gain
§
Incorporate cardiorespiratory and strength-training activities
§
Spot-reducing does not work
§
○
Break bad habits w/ behavior modification
Focus on changing eating behaviors that contribute to weight gain
or impede weight loss
Keep a food log□
Control environmental cues that trigger eating when hungry □
Learn how to better manage stress□
§
○
-
How Can Weight Loss Be Maintained?
Successful weight maintainers
Maintain the energy-gap reduction in kilo-caloric need to maintain
the weight loss
Reduce kcal intake by decreasing portions and fatty foods□
Eat smaller, more frequent meals; make sure it does not turn
into "grazing"
□
Maintain a high level of physical activity □
§
Weekly self-weighing can help individuals maintain their weight loss
§
○
-
Healthiest Way to Gain Weight?
Gaining weight is challenging for those who are underweight
○
Goal is to gain muscle, not all fat
○
Methods to do this
Add 500 kcals in addition to daily energy intake
Adds about 1 pound of extra body weight per week□
§
Choose more energy-dense foods
§
Include regular exercise and resistance training
§
○
-
Medical Interventions for Extreme Obesity
Weight-loss medications
Sibutramine (Meridia)
Suppresses appetite□
§
Orlistat (Xenical)
Inhibits fat absorption□
§
Lorcaserin
Stimulates satiety and may reduce food intake□
§
○
Evaluate the side effects of all weight loss medications to determine if
experiencing these effects are worth taking the drug
○
Bariatric Surgery Restricts Food Intake
Gastric bypass surgery
Post surgery
Consume small, frequent meals
®
Supplement: iron, vitamin B12, calcium and vitamin C
®
□
Weight loss
5 to 15 pounds/ week in the first 2 to 3 months
®
One to 2 pounds/ week after first 6 months
®
□
Eliminates
Diabetes (76.7%)
®
Hypertension (70%)
®
□
§
Gastric banding
Weight loss is slower compared to gastric bypass surgery□
Banding is less invasive □
§
○
-
Ch. 15 Weight Management
Wednesday, April 18, 2018
2:23 PM
Why is Weight Management Important?
Weight management is maintaining body weight w/in a healthy range
(18.5 to 24.9)
○
Healthy weight is a body weight that does not incr. risk for developing
weight-related health problems or diseases
○
Healthy weight lowers risk for chronic disease
○
-
AMA Considers Obesity a Disease
In 2013, American Medical Association declared obesity a "disease"
○
Benefits to declaring it a disease
Provides a clear warning of health hazards of being overweight
§
May make it easier for individuals to get insurance coverage for
treatment
§
More research funding may ne allocated to addressing the obesity
problem in the U.S.
§
○
Downsides to declaring it a disease
It may encourage more use of drugs and medicals procedures to
address the epidemic rather than encouraging lifestyle changes
§
Cost treating obesity will skyrocket
§
○
-
Being Overweight or Underweight Carries Social and Psychological Risks
Overweight people are treated differently from people at a normal weight
Suffer more discrimination
§
More likely to be denied job promotions and raises
§
Obese females are less likely to be accepted into college, esp higher
ranked colleges
§
○
Obese people have higher rates of suicide and are more likely to use
drugs and alcohol
○
Individuals who are underweight are more likely to be at greater risk for:
○
-
How is Food Regulated?
Appetite is the desire to eat food whether or not there is physical hunger
○
Hunger and satiety affect the desire to eat and to stop eating
○
The brain and hormones control feeding
○
Satiety is triggered by the ventromedial nucleus (part of hypothalamus,
which controls hunger/ fullness)
Cholecystokinin (CCK) and peptide YY (PYY)
Secreted by the small intestine to stimulate satiety
□
§
Leptin
Produced in adipose tissue (fat tissue)
□
Decreases hunger and food intake
□
Regulate amount of fat stored
□
Decreased w/weight loss and intake of certain vitamins and
minerals (zinc supplements, low vitamins C and A)
□
Get to a certain point where you body doesn't respond
□
§
○
Certain macronutriens, esp protein, promote satiety and reduce food
intake
○
Hunger is controlled by lateral hypothalamus
Ghrelin
§
Neuropeptide Y
§
Leptin
§
○
-
How do Fat Cells Form and Expand?
Growth of fat cells (adipocytes) occurs in 2 ways
Can expand to store more fat (hypertrophy)
§
Once filled to capacity, stimulate the production of more fat cells
(hyperplasia)
§
○
The # of Fat Cells in the Body Never Decreases
Average adult has 30 to 50 billion adipocytes, which hold 0.4 to 0.5
micrograms of fat each
§
○
Fat Cells can Grow and Shrink
Enzymes control the size of fat cells
§
Heavier people have increased LPL activity
§
○
-
How Do Genetics and Environment Influence Obesity and Weight Management?
Nutrigenomics and epigenetics may influence weight control
Nutrigenomics:
§
Epigenetics:
§
Food and nutrients are a factor that can activate or repress certain
genes
§
○
Genetics can Influence Hunger, Satiety, and Insulin Response
Altered genes may determine an individual's hormonal response in
the presence of food, affecting hunger and satiety
§
Multiple genes receive signals that change their structure, which
then turns them on or off
§
Genes can be turned on or off by a combo of DNA methylation and
histone modifications
§
Genes are transcribed through transcription factors that are
activated by cellular signaling cascades
§
Adipocytes secrete the hormone adiponectin
Improves the body's response to insulin□
§
Some individuals store more fat w/ excess energy intake
§
Genes may cause different rate of thermogenesis
§
Genetic "set point" theory
§
Populations which are genetically prone to being overweight or
obese can overcome their genetic predisposition by engaging in
regular exercise and eating healthy
§
○
Environmental Factors can Increase Appetite and Decrease Physical
Activity
Our current environment makes it easier to have positive energy
balance and gain weight
§
Environmental factors involved w/ obesity
Lack of time□
§
An abundant food supply and portion distortion
§
Lack of physical activity and increased sedentary behavior
People do less manual labor in their jobs□
The more people drive, the less they engage in physical
activity
□
More time is spent in front of the TV or computer□
§
○
-
How Can You Lose Weight Healthfully?
Strive for a reasonable rate of weight loss
Lose 10% of body weight over 6 months
§
Modify diet, physical activity, and behavior
§
○
Remember that kcals count
Choose lower kcal foods
§
Reduce portion sizes
§
Increases kcals burned
§
○
Eat more vegetables, fruit, and fiber
○
Avoid mindless eating
○
Adding volume to meals
○
Adding some protein and fat to meals
Protein promotes satiety
Focus on lean protein□
§
Fat slows movement out of the stomach
Focus on healthy fats in moderation□
Limit fats high in saturated-fats□
§
○
Use MyPlate as a weight-loss guide
○
Increase physical activity to lose weight
Increases kcals burned and displaces sedentary activity
§
60 to 90 minutes daily of moderate-intensity physical activity to aid
in weight loss, prevent weight gain
§
Incorporate cardiorespiratory and strength-training activities
§
Spot-reducing does not work
§
○
Break bad habits w/ behavior modification
Focus on changing eating behaviors that contribute to weight gain
or impede weight loss
Keep a food log□
Control environmental cues that trigger eating when hungry □
Learn how to better manage stress□
§
○
-
How Can Weight Loss Be Maintained?
Successful weight maintainers
Maintain the energy-gap reduction in kilo-caloric need to maintain
the weight loss
Reduce kcal intake by decreasing portions and fatty foods□
Eat smaller, more frequent meals; make sure it does not turn
into "grazing"
□
Maintain a high level of physical activity □
§
Weekly self-weighing can help individuals maintain their weight loss
§
○
-
Healthiest Way to Gain Weight?
Gaining weight is challenging for those who are underweight
○
Goal is to gain muscle, not all fat
○
Methods to do this
Add 500 kcals in addition to daily energy intake
Adds about 1 pound of extra body weight per week□
§
Choose more energy-dense foods
§
Include regular exercise and resistance training
§
○
-
Medical Interventions for Extreme Obesity
Weight-loss medications
Sibutramine (Meridia)
Suppresses appetite□
§
Orlistat (Xenical)
Inhibits fat absorption□
§
Lorcaserin
Stimulates satiety and may reduce food intake□
§
○
Evaluate the side effects of all weight loss medications to determine if
experiencing these effects are worth taking the drug
○
Bariatric Surgery Restricts Food Intake
Gastric bypass surgery
Post surgery
Consume small, frequent meals
®
Supplement: iron, vitamin B12, calcium and vitamin C
®
□
Weight loss
5 to 15 pounds/ week in the first 2 to 3 months
®
One to 2 pounds/ week after first 6 months
®
□
Eliminates
Diabetes (76.7%)
®
Hypertension (70%)
®
□
§
Gastric banding
Weight loss is slower compared to gastric bypass surgery□
Banding is less invasive □
§
○
-
Ch. 15 Weight Management
Wednesday, April 18, 2018 2:23 PM
Document Summary
Weight management is maintaining body weight w/in a healthy range (18. 5 to 24. 9) Healthy weight is a body weight that does not incr. risk for developing weight-related health problems or diseases. In 2013, american medical association declared obesity a disease Provides a clear warning of health hazards of being overweight. May make it easier for individuals to get insurance coverage for treatment. More research funding may ne allocated to addressing the obesity problem in the u. s. It may encourage more use of drugs and medicals procedures to address the epidemic rather than encouraging lifestyle changes. Being overweight or underweight carries social and psychological risks. Overweight people are treated differently from people at a normal weight. More likely to be denied job promotions and raises. Obese females are less likely to be accepted into college, esp higher ranked colleges. Obese people have higher rates of suicide and are more likely to use drugs and alcohol.
