L1 & L2 | The Psychology of Eating and Drinking

Introduction

• The psychology of eating and drinking is the topic of the course.
• The instructor is Dick Stevenson ([email protected]).
• Tutorials begin next week.
• Students should obtain the course handbook from iLearn.
• The handbook includes the course timetable and other important information.

Why study Feeding & Drinking?

• Eating and drinking are essential for survival.
• Evolutionary forces have shaped our behavior and physiology related to ingestion.
• Colour vision has evolved in connection with primates and ripe fruit.
• A drive to consume sugar and fat is hardwired.
• Bipedalism is connected to predator detection and hunting.
• Physiologies are important for reasons such as survival, lower IQ and obesity.
• Malnourishment and obesity are global concerns.

Why study Feeding and Drinking? (continued)

• A significant portion of the world's population, over 1.2 billion people, are undernourished and hungry.
• Another 1.2 billion people are dealing with overweight and obesity.
• This is an important issue due to its consequences, such as lowered IQ, lost earnings, and entrenched poverty.
• Obesity is costly and leads to shortened lifespans and chronic diseases.
• Understanding obesity and malnourishment requires looking at socioeconomic, biological, behavioral, and psychological factors.

Why study Feeding & Drinking? (continued)

• In the West, 15% of adults are alcohol dependent.
• This results in 100,000 preventable deaths annually in the US alone
• Studying biological, psychological, social, and socioeconomic factors that contribute to alcohol dependence is necessary.
• Processed foods are also considered in relation to dependence.

Answers?

• Studying eating disorders, obesity, starvation, and alcohol dependence requires understanding typical ingestion behaviors.
• The factors behind those decisions must be considered.
• Societal factors, the economy, and health must be considered.

Course Structure

• The course will start with examining the basics of Ingestion.
• Key components of ingestion are energy metabolism, food types, the digestive system, water balance, and eating and drinking strategies in other animals.

Then...

• Key topics for upcoming weeks detail how we perceive food and drink, the nature of thirst, food preferences, food taboos, psychobiology of food intake, & the food system.
• Furthermore, the course will explore obesity, starvation, eating disorders, body image, dieting, and related topics.

Things you need to know

• All lectures and videos are online.
• Some videos cannot be shown using iLearn.
• There will be a review session in the last week of the course.
• The course materials (including lecture notes, Logue chapter, and tutorial papers) are compulsory.
• Please refer to the Course Handbook for additional information.

Assessment

• The end-of-semester exam is 50% multiple choice.
• The exam will cover the material presented in lectures. (excluding videos)
• The second 50% of the assessment is the personal research project.

Energy Metabolism

• Food provides energy to the body
• The body converts food into mechanical energy for muscles, electrical energy for nerves, and heat to maintain temperature.
• Key food components are carbohydrates, proteins, and fats, providing significant energies in kcal.

What are the bodies energy needs?

• The body expends energy at rest (BMR).
• Roughly 70-80% of the food consumed is used to maintain BMR.
• BMR varies with age, pregnancy, and muscle mass.
• Activity levels affect energy expenditure, as do illness & various other factors.

Calculating Energy Needs

• Most charts providing caloric intake are based on BMR and activity level estimations.
• Activity level ranges from light to heavy.
• Heavy activity correlates with physical activity for much of the day.

Consequences

• Average Australians require approximately 3270 kcals per day with moderate levels of activity.
• In contrast, concentration camp inmates consumed around 700 kcals daily.

Carbohydrates, Protein, Fats

• Detailed information concerning the chemical composition & functionality of carbohydrates, fats and proteins are covered here.
• Many references are included on the composition and functionality of them.

Micronutrients, Minerals

• The importance of various essential minerals and micronutrients.
• The importance of balance in diets is highlighted.
• Key minerals covered include: Calcium, Phosphorus, sodium, potassium, Magnesium.
• Trace minerals also receive attention.

Human Digestive System

• Detailed information on the digestive system's function, organs, and components is covered.
• Key processes like mechanical, chemical digestion and enzymatic breakdown are included.

Human digestive system-gross anatomy

• Descriptions and diagrams of the digestive system's organs in detail.
• Descriptions encompass the mouth, stomach, small intestine, large intestine, accessory organs (liver, pancreas, gallbladder)

Small intestine , Large intestine

• Detailed description concerning the small intestine, and its length & features.
• The large intestine is described with details concerning length, and components.
• A diagram provides additional context.

Water balance

• Water is essential from an ecological context.
• Detailed quantities of water loss from the body through various channels are provided.
• A description exists related to daily water consumption.

Conclusion

• The course has covered the various feeding strategies employed by diverse species.
• The concepts of hunger and satiety vary across animal species, in this context.

Feeding in Parasites

• Defining characteristics of parasitic feeding are provided.
• A parasite's evolutionary adaptations, reproduction, and lifestyle necessitate the host's survival for their existence.

Feeding in omnivores

• Description of omnivorous feeding strategies
• The advantages and disadvantages of this feeding strategy are discussed.
• Details concerning the relationship of the omnivorous feeding style to humans.

Advantages and Disadvantages of Omnivorism

• Animals that consume a wide range of foods thrive in variable environments.
• They can survive periods of scarcity and benefit when certain foods abound.
• Omnivorous animals have a flexible and adaptable approach.
• Consuming a wide variety of foods poses risks for omnivores (nutrients and toxins).

Consequences (omnivores)

• A method to resolve omnivore paradoxes is to develop sensory systems that can recognize the suitability of food.
• Learning about nutritional value, safety, seasonality of foods, and learning from others.
• Omnivores tend to avoid bitter foods, rotten foods, and unfamiliar foods.

Conclusions

• The course has evaluated various feeding strategies.
• The key topics will form the topics for future lectures.