Question

1. Describe three major ways that the body uses energy AND discuss how an individual may influence one of them. (3 points)

2. Why can’t people speed up their basal metabolic rate (BMR) with exercise or with supplements? (2 points)

3. a)Describe how hunger and appetite differ. (2 points)

b)Which of these can be associated with obesity and why? (2 points)

4. How are the self-perceptions of a person with bulimia nervosa different from those of a person with anorexia nervosa? How are they similar? (3 points)

5. List any three serious health consequences of anorexia nervosa AND explain how this eating disorder can cause these consequences. (3 points)

Answer 1

1)Three major ways body uses energy:

Eating digesting and metabolising food: metabolism is the process by which an individual converts the calories from the food into energy. The body uses 10% of the total energy for the process of metabolism.

During physical exercises: About 20 percent of an average active person's energy is required to burn kilojoules during physical activity. During exercise, the body relies on three different energy systems, which work independently of one another but may all be used at the same time. The ATP-PCr system is used during brief bursts of exercise, such as sprinting or jumping. A chemical reaction causes the ATP-PCr molecules to separate, which releases the energy required for contraction of the muscles. Other types of short, intense activity may rely on the glycolytic energy system, which is responsible for breaking down glucose stored in the liver and skeletal muscles and converting it to ATP – adenosine triphosphate, the chemical form of raw energy in your body. Finally, the aerobic system uses oxygen to break down fat stores for energy that the body relies on for a lengthy, continuous energy supply, such as it needs during a long run, swim or cycle.

being at rest:

Being at Rest: most of the energy the body uses each day – 50 to 80 percent – is needed for being at rest, otherwise known as basal metabolism. This is the minimum amount of energy required to maintain the body's vital functions, such as breathing, blood circulation and organ function. The rate at which energy is used for these vital functions is the basal metabolic rate (BMR). Not everybody has the same BMR; genetics, sex, age, height and weight are all factors. Your BMR drops as you get older because muscle mass decreases. To maintain a good BMR and become more energy efficient, increase your overall calorie burn through exercise.

2) BMR depends on various factors such as age, gender, genetics, body built etc. Which are unmodifiable hence we can't speed up BMR my exercises and supplements.

3)A)Hunger is not the same as appetite. Appetite is the desire to eat. While hunger is a cue from your body, appetite is a cue from your brain. Another way to think about this is that appetite is a luxury and a choice -- a modern concept that appeared once humans had the option of choosing when and what they wanted to eat.

Each one of us is programmed to be hungry when our bodies need nutrients to survive; it's experienced as a drive to find food, and if we don't satisfy that need we'll feel an unpleasant sensation

Appetite, on the other hand, is more of a learned behavior; as the body's different senses trigger a desire for energy (i.e., food), even when we may not need it, over time we can respond to appetite cues that result in eating. This explains how one person can choose to eat poorly while another person chooses nutrient-rich foods when hunger strikes. Put another way, whereas hunger is a physiological need, appetite is a psychological desire. Anyone who has ignored hunger or over responded to it knows what having an appetite out of control can be like. It's what leads to ingrained eating behaviors that lead to problems with weight.

B) hunger is a natural response whenever there is a need for energy and it is a physiological need. Appetite is a psychological response and a learned behavior in other words the desire to eat even when we may not need it this appetite plays a role in obesity. Appetite has recently received the attention of researchers in developing countries due to the increasing prevalence of obesity. There are multiple complex mechanisms involved in food intake. The satiety level and the physiological state of a person are responsible for appetite expression. Specific manipulations of macronutrients have the potential to affect appetite control. Certain pharmaceutical formulations and sensitizer compounds/chemicals can also be used as appetite suppressants either orally or intravenously. Several aspects related to appetite control and obesity have been briefly reviewed in view of the current scientific and commercial trends.

4) Anorexia nervosa is a severe psychiatric illness characterized by intense fear of gaining weight, relentless pursuit of thinness, deep concerns about food and a pervasive disturbance of body image. The person feels that he/she is obese even though they are underweight.

Bulimia nervosa is characterized by disturbed body image, repetitive binge eating, and compensatory behaviours such as self-induced vomiting, laxative abuse, or fasting. Body image dissatisfaction and eating disordered behaviours (e.g. food restriction, purging, and binge eating) can affect men and women of varied ages, races, and cultural backgrounds. Body dissatisfaction is defined as a negative subjective evaluation of the weight and shape of one’s own body. Body dissatisfaction predicts the onset, severity, and treatment outcomes of eating disorders. A core component of body dissatisfaction is appearance-based social comparisons. In this context a study on self-perception of body image of women in Riyadh in 2018 revealed that a sudden spurt in obesity after marriage is leading to shift of higher percentage of women from positive to negative perception. Overall, an underestimation of body weight in terms of BMI was found among the participants. Such misconceptions should be addressed in view of the high obesity prevalence. It was also evident that positive and negative body image perception will lead to eating disorders in adolescents.

Both anorexia and bullemia are eating disorders and both are characterised by disturbed body image perception.

5) Consuming fewer calories than you need means that the body breaks down its own tissue to use for fuel. Muscles are some of the first organs broken down, and the most important muscle in the body is the heart. Pulse and blood pressure begin to drop as the heart has less fuel to pump blood and fewer cells to pump with. The risk for heart failure rises as the heart rate and blood pressure levels sink lower and lower.

Severe, prolonged dehydration can lead to kidney failure.

Inadequatenutrition can decrease the number of certain types of blood cells.

Anemia : when there are too few red blood cells or too little iron in the diet. Symptoms include fatigue, weakness, and shortness of breath.Malnutrition can also decrease infection-fighting white blood cells.