Biology Chapter 3.4 Body Fat & Health Perception of Beauty How much body fat should we have? Women need more fat than men to maintain fertility. The range for body fat for women is 12% to 32%. The range for body fat for men is 3% to 29%. Women store more fat on their breasts, hips, and thighs. Women also have an 8% thicker layer of tissue called the dermis under the skin unlike men. That's why a women's muscles look smoother and less defined. Body fat increases with age and larger boned people have more fat. BMI (Body Mass Index) The BMI is a better approximation of ideal weight but it is not perfect. BMI ignores differences in frame size, sex, or muscle mass. For example, an athlete with a lot of muscle will weigh more than a similar size person with a lot of fat because muscle is heavier than fat. If your BMI is high, you may be at increased risk for diseases associated with obesity. Body Mass Index Obesity Rates The number of Canadians, who are obese, has risen dramatically in recent years. In 2004, 23.1% of Canadians older than 18 are obese. In Canada, children obesity has substantially increased between 1989 and 2004 with rates in boys increasing from 2% to 10% and rates among girls increasing from 2% to 9%. About 4% of the adult population is obese in Korea, and about 30% are overweight (including obese). Overweight rates will increase by a further 5% within ten years. In the United States, 1 in 3 adults are obese (33%). This is all due to junk food, fast food, and lack of exercise. Diabetes Insulin is a hormone made by beta cells in the pancreas. Insulin converts glucose into energy. People with diabetes cannot produce or respond to insulin. As a result the level of glucose in the blood increases. Diabetes There are two types of diabetes: Type 1 ( insulin dependent diabetes mellitus) IDDM Type 2 ( non insulin-dependent diabetes mellitus) NIDDM Type 1 Diabetes Starts in childhood The child cannot produce insulin because their immune system mistakenly destroyed their beta cells. When the body cannot produce insulin, daily injections of the hormone are needed. Type 2 Diabetes Happens at age 40 and in the obese. This occurs because the pancreas produces a lower amount of insulin or the target cells are not responding to secreted insulin. People with type 2 diabetes can control blood glucose levels through diet and exercise. Sometimes, people with type 2 diabetes take insulin injections. Diabetes in Korea ppt Questions 4 1.Why do women need more fat than men? 2.What is the range of body fat a woman should have? 3.What is the range of body fat a man should have? 4.Where do women store more fat? 5.What does BMI ignore? 6.What is insulin? 7.What does insulin do? 8.What are the 2 types of diabetes? 9.Who has type 1 diabetes? 10.Who has type 2 diabetes? 11.What other diseases can occur because of diabetes? Hypertension Hypertension is the same as high blood pressure. This causes increased stress on the circulatory system and the heart to work too hard. A person with hypertension is 6 times more likely to have a heart attack. Measure Blood Pressure Blood pressure has two numbers: The higher number, called the systolic blood pressure, is the blood pressure exerted on the walls of blood vessels when the heart contracts. The lower number, called the diastolic blood pressure, is the pressure between contractions of the heart when the heart is relaxing. https://youtu.be/Gmic13mvsgo Normal blood pressure is 120/80. High blood pressure is seen at 140/90 The more obese you are, there is more demand on your CVS to carry oxygen and nutrients throughout your body, which indicates there is more demand on your heart. Heart Attack When there is a sudden interruption in the supply of blood to the heart caused by a blocked vessel supplying the heart. Stroke When there is a sudden loss of brain function that results when blood vessels supplying the brain are blocked or ruptured. Heart Attack & Stroke Cholesterol Low-density lipoproteins LDLs have more cholesterol than protein. carries cholesterol to cells where it is used to make plasma membranes and hormones. High-density lipoproteins HDL Have more protein than cholesterol HDL takes excess cholesterol from the body and returns it to the liver, where it makes bile. The bile enters the small intestine where it exits the body in the feces. Doctors look at your LDL and HDL amounts. If your total cholesterol level is above 200 or your LDL level is above 100, then your doctor will tell you to eat less cholesterol and saturated fat. They may recommend a plant-based diet. Good Cholesterol Cholesterol is in cell membranes to help maintain their fluidity. It is the building block for steroid hormones such as estrogen and testosterone. You make enough cholesterol so you do not need it from your diet. Cholesterol filled, athero- sclerotic vessels increase your risk of heart disease and stroke. Fat deposits narrow the heart's arteries. So, less blood can flow to your heart. Less blood flow to the heart can cause chest pain or angina. A complete blockage can lead to a heart attack. This can cause heart damage. Bad Cholesterol you can have fat buildup in arteries of the brain. this can lead to stroke. if brain tissue dies, permanent brain damage can happen. Anorexia Self-starvation 1 in 5 women and 1 in 20 men in universities are starving themselves to death. Bulimia Binge eating followed by vomiting is called bulimia. binge eating is when you eat a lot of food and then prevent it to turn into fat by vomiting. Anorexia and Bulimia because anorexics have no body fat, they stop menstruating. This is called amenorrhea. leptin signals the brain saying that there is not enough body fat to support a pregnancy. hormones (estrogen) which regulate menstruation are blocked and menstruation stops Amenorrhea can be permanent and cause sterility in anorexics. Anorexia and Amenorrhea Anorexia and Osteoporosis estrogen helps maintain strength and size of bones when estrogen is low in the body, anorexics can have weak bones, resulting in osteoporosis. Bulimia Bulimics can rupture their stomach through forced vomiting. they often have dental and gum problems caused by stomach acid being forced into their mouth during vomiting. they can become fatally dehydrated. Obesity and Anorexia or Bulimia Food Pyramid: Eat Healthy Questions 5 1.What happens in a heart attack? 2.What happens in a stroke? 3.What is hypertension? 4.What numbers do you need to measure blood pressure? 5.What are LDLs? 6.What are HDLs? 7.Do you need cholesterol from your diet? 8.What is bulimia? 9.What is anorexia? 10.What is amenorrhea? 11.Can amenorrhea be permanent in anorexics? 12.Can anorexics have osteoporosis? 13.Why do bulimics have dental and gum problems? 14.Why is the yellow triangle in the food pyramid small? What does it represent?