Physical Wellness Chapter 9 Body Composition

Medical costs for the obese are much higher than for healthy-weight people. How much higher?

$2460 more per person per year

Body fat is stored primarily in 2 places. What are they and how much is generally in each?

(1) around (and in) the organs in the abdominal cavity. This is called visceral fat. (2) Just beneath the skin. This is called subcutaneous fat or peripheral fat. Fat is stored about half and half, but that can vary with genetic tendencies and amount of exercise. Cardio exercise tends to burn visceral fat more.

What is the optimal rate of fat loss, and how can it best be done?

1-2 pounds a week. To lose 1 pound (3500 cals), that is 500 cals per day. 250 in less food and 250 in more exercise. Both cardio and resistance training are important to do.

Why was BMI chosen to be the indicator of body composition, despite its drawbacks?

1. All the others have drawbacks, too, of • Cost / availability to the public • Need for training • Accuracy

What is the impact of obesity on the nation?

1. High (and increasing) health care and health insurance costs for families and for all taxpayers. 2. It impacts the work force and therefore productivity and our nation's economic health. 3. The military, police and fire departments cannot find enough healthy applicants.

What are some good answers to an exam question about the social and environmental factors that lead to obesity?

1. The 'pleasure trap' makes us want to eat unhealthy food 2. Stress eating can cause people to gain weight. 3. Many neighborhoods are not walkable. 4. The way your parents eat influences you. 5. The way your friends eat influences you.

my BMI

18.6

How many calories are there in a pound of fat?

3500

If someone has an endomorph somatotype, leptin resistance, a high set point, and a bunch of susceptibility genes for obesity, should they just give up?

A reasonable goal would be to stay as healthy as a nutritious diet and plenty of good exercise will allow them to be.

What evidence do we have that genetics plays a role in obesity?

Adopted children tend to have the BMI of their biological parents, not the people who brought them up.

So, what are the advantages of doing both aerobic and resistance exercises when trying to control weight?

Aerobic exercise: • Elevates metabolic rate during, and for a while after, exercise. • Counteracts the Dessert Island Syndrome if you are reducing calories also. Resistance exercise: • Keeps or even builds your muscle mass, thereby burning up more calories even while you rest. Helps you avoid the yo-yo effect so you don't increase your percent fat after every failed diet.

What is the most dangerous eating disorder?

Anorexia nervosa

What is the best way to decide your ideal weight

Ask your doctor. They are beginning to give patients their BMI now, but that may not be the whole story.

What is BMI, and what range means a person is overweight? Obese?

BMI stands for Body Mass Index. It is not the same as % of body fat. It is not a % - it is just a number, an index. BMI is one way of estimating body fatness. It is the method that the federal government has chosen, and doctors are now required to record each patient's BMI in their records so that nationwide statistics and changes can be tracked. • Underweight: BMI less than 18.5 • Normal weight: BMI of 18.5-24.99 • Overweight: BMI of 25-29.99 • Obese: BMI of 30 or more • Morbidly obese: BMI of 35 or more

Which uses more calories - BMR, physical activity or brain activity?

BMR uses 60-70% of caloric requirement

Unless and until government regulations force food manufacturers to make more nutritious foods, or make the nutrition facts more visible, what can consumers do?

Become educated consumers. And . . . pack a lunch!

How does inflammation affect obesity?

Belly fat releases inflammatory compounds, increasing inflammation in the body. Inflammation contributes to insulin resistance. That can cause obesity. Obesity (especially belly fat) increases insulin resistance and increases inflammation. So inflammation, insulin resistance and obesity reinforce each other, often leading to type 2 diabetes. Being sedentary and eating an unhealthy diet promote inflammation and also obesity.

What are some other eating disorders?

Binge eating Bulimia - bingeing and purging Anorexia athletica is a danger for athletes who need very slim bodies. Female athlete triad is a danger for female athletes. Muscle dysmorphia is a danger for male models.

What does 'somatotype' mean?

Body shape - there is a genetic tendency for each of us to have a certain body shape.

What are 'obesogens'?

Chemicals in foods, products and the environment that may increase fat accumulation by disrupting the endocrine system, thus affecting hormonal balance.

What are the 3 somatotypes?

Ectomorph (linear) Mesomorph (muscular) Endomorph (round)

What is epigenetics, and how does it influence obesity?

Epigenetics is the science of how genes get turned on or not turned on - or the extent to which they get turned on. Environmental factors can influence this One mechanism for that may be our 'microbiota' - the bacteria in our intestinal tract. Animal studies have found that some microbes in the colon influence metabolism and how carbs and fat are digested, affecting the risk for obesity

What is the clinical definition of 'obesity'?

Excessive body fat.

What are the genetic, hormonal and metabolic influences?

Genes play a role in how many calories we burn. Genes may disrupt the way the hormones leptin and grehlin work, causing someone to not feel full when they really are full. Genes can influence where on your body you are likely to store fat.

What is BMI based on?

Height and weight only

Which states have the highest and lowest obesity rates?

Highest: Mississippi Lowest: Colorado

How does socio-economic level affect obesity?

If you have 'food insecurity' (anxiety about whether you will be able to supply enough food for yourself and your family) you are more likely to choose food that is cheap and filling over food that is healthy and expensive. Obesity, not surprisingly, is more prevalent among the poor than among the wealthy. It is also linked to lower levels of education.

Describe the desert island syndrome

If you suddenly cut back on calories, your body, which is incredibly complex, senses that your food supply has been cut off, and tries to do everything it can to keep you alive until the food supply can be re-established. One of the things it does is reduce your metabolic rate. This is not good news. This makes it harder to burn fat.

What is my formula for losing fat without losing muscle?

Increase your exercise, especially aerobic and resistance training. Decrease your food intake, especially fats, sugars and alcohol.

Why is obesity considered a 'gateway' chronic disease?

It can lead to just about every other chronic hypokinetic disease and condition.

For fat stored under the skin, is the fat under the muscle layer, or the muscle layer under the fat?

It goes skin, fat, muscle. So when they do a skinfold test, they have to be sure to only get fat, no muscle. That's why they wiggle the skin.

Do people have less willpower now than they did 30 years ago, before the obesity epidemic began?

It is much harder to lead a healthy lifestyle now than it was then.

Why is resistance training a good idea when you are trying to lose fat but not muscle?

Muscle uses calories just sitting there in your body, so your resting/basal metabolic rate is higher with more muscle. Muscles are our friends.

BMI values tend to correlate with body fatness in most people, but for whom is BMI not accurate? Why?

Muscular people, because muscle weighs more than fat does.

If I do a lot of crunches, will that get rid of the layer of fat on my tummy?

No. Crunches will tighten and tone the muscles, which is great, but to get rid of fat, I should decrease my calorie intake and do aerobic exercise. That burns the fat from wherever it is in the body.

What are the most important health consequences of obesity for the individual?

Obesity often leads to other chronic diseases. The most deadly are heart disease, type 2 diabetes, stroke and some cancers.

What are some social and cultural influences on obesity?

One obese person in a family or group tends to make others obese. We cook at home less. Some cultures make it harder to reduce calories. In some cultures, it is frowned upon for women to participate in sports or workouts that require pants and make them sweat. Parents influence weight-related tendencies by example and by what food they keep in the house.

What are the 2 biggest contributors to our health care costs?

Smoking and obesity

Why can genetic factors, by themselves, not account for the rapid increase in obesity rates in this country?

The gene pool does not change that fast.

Your body composition is the result of 2 things. What are they?

The number of calories you take in and the number of calories you use. You use them mostly (60-70%) for Basal Metabolic Rate, not exercise.

What are leptin and grehlin, and how do they affect fatness?

They are hormones that help to regulate appetite and food intake. • Leptin makes us feel full. • Grehlin makes us feel hungry. A resistance to leptin or a leptin deficiency or any other discombobulation of these hormones could cause overeating.

What happens to BMR (and RMR) as you age?

They decrease

What is the goal of the Let's Move campaign, and who is behind it?

This is Michelle Obama's effort, and its goal is to 'reverse the epidemic of childhood obesity within a generation'.

What proportion of adults are overweight and obese in this country?

Total overweight: 2/3 (66 or 67%) Overweight but not obese: 1/3 (33%) Obese: 1/3 (33%)

What led researchers to the conclusion that regular physical activity over a lifetime may overcome the effects of inherited risk?

Twin studies have shown that obesity and diabetes can often be prevented by lifestyle changes.

What kinds of problems are associated with a lot of belly fat?

Type 2 diabetes, Heart attack, stroke, chest pain, breast cancer, early death

Which is more dangerous for your health - visceral (aka central or belly or abdominal) fat or subcutaneous (aka peripheral) fat?

Visceral fat. The fat stored around organs is more dangerous that the fat stored under the skin. It leads to inflammation and insulin resistance, among other things.

How does behavior influence obesity?

We spend too much time sitting.Calorie intake has increased. Sugar consumption has increased. PA decreased. If you burn fewer calories but do not reduce your food intake, you gain weight and may become obese. Sleep may affect risk for obesity. Some studies suggest that lock of sleep affects metabolism, or leptin and grehlin, or insulin and fat storage.

Is it possible to be both fit and fat?

Yes. it is possible to be overweight and still have a good metabolic profile -

How does your set point make it difficult to keep weight off, if you gain and lot and then lose a lot?

Your body decides that your greater weight should be maintained, so it slows your metabolism to retain that weight. A person who has gained weight and then lost it cannot eat as much (given equal exercise regimens) as a person who is the same weight but has never gained a lot of weight and then lost it.

Describe the yo-yo effect

if you lose weight through reducing calories and doing aerobic exercise with no resistance training, some of the weight you lose will be muscle. Then, if you should start eating more and exercising less and put weight back on, all of that will be in the form of fat. If this occurs several times over the course of 15 or 20 years, you can see that your body composition would gradually become more fat and less muscle.

What ideas do you have for reversing the obesity epidemic?

nudges

What is meant by the term 'set point'?

the weight that your body 'wants to be' - this refers to the way the body protects current weight and resists change.

Obesity is surpassing what, as the number one cause of early death?

tobacco

What does BMR stand for, and what does that mean?

• Basal Metabolic Rate. • The rate at which you burn calories to do only the minimal things needed to keep your body functioning (heart beating, lungs breathing, liver and kidneys functioning, eyelids blinking), not even digesting. To have this tested, you have to be in a testing facility the night before so they can be sure you have been only resting for 8 hours, with no activity and no food.

What are some other possible influences that are being explored?

• Diseases such as hypothyroidism. • Increased stress and feelings of lack of control. • Medications associated with weight gain, such as some for depression, diabetes, hypertension, epilepsy, contraception. 'addictive' properties of many processed foods.

How do the federal government and the food industry affect obesity in this country?

• In the U. S., we subsidize the growing of wheat, corn and soy, but not the growing of fruits and vegetables. Therefore corn-fed beef and pork, corn oil and corn syrup are plentiful and cheap, and the food industry has been able to offer them at low prices and still make a profit.

What does RMR stand for, and what does it mean?

• Resting Metabolic Rate. This includes some recent activity, such as driving to the testing center. Testing for this does not require an overnight at the testing facility, but they do want you to fast.

There are several other methods of estimating body fat content. What are they?

• The 'gold standard' is the DXA (also called DEXA) scan, which is quite accurate, but is expensive and requires a doctor's prescription • Other methods are: o Underwater weighing o The bod pod o The skinfold test Bioelectrical impedance

Why is aerobic exercise good at burning fat?

• The increased demand on your muscles, especially your leg muscles which are large, requires a temporary increase in your metabolic rate. Not only is your metabolic rate increased during exercise, but it returns to normal gradually, not immediately, so it stays elevated for a few hours after exercising, burning more calories than normal that whole time.