Weight Management
BMI
The body mass index (BMI) is used to estimate the amount of body fat. Calculation is by dividing the weight (in kg) by the height in meters squared.
BMI=Weight in kg ÷ height in m2
BMI may not be accurate:
·In people who are body builders/athletes (because of the weight of their muscles)
·Pregnant women (because of the weight of the growing baby).
·Elderly
·People with physical disability (those unable to walk and eventually have muscle wasting)
·People with anorexia nervosa
·Extreme obesity
A healthy BMI range for adults is 19 to 25.
However, when considering the weight and health risks, the measurement of waist circumference is a better indicator than BMI.
Considering the waist circumference in men and women:
|
Men |
Women |
Remarks |
|
Above 94 cm |
Above 80cm |
Overweight |
|
Above 102cm |
Above 88cm |
Obese |
BMI ranges:
Under 19 – Underweight
19 to 25 – Normal
25 to 30 – Overweight
Over 30 - Obese
Measuring BMI in children and adolescent:
BMI is calculated the same way for children and adults. However, the criteria of interpreting the result are different. This is due to the fact that children are constantly growing and the amount of their body fats will always change. Another reason is that the amount of body fats differs between girls and boys. Hence, when determining the healthy BMI cut off, the age and sex of children are considered.
The BMI chart for children is used to assess obesity and overweight from ages 2-20.
To understand better, here is an example from CDC (Center of Disease and Control and Prevention)
Different BMI numbers for a 10-yr old boy:
Obesity
Obesity means having excess body fat and BMI is greater than 30. Or a waist circumference of 102cm or above for men and 88cm or above for women.
Obesity can lead to diabetes, high blood pressure, cardiovascular and other chronic diseases.
Risks associated with obesity:
1. Insulin resistance- a risk factor in development of diabetes and heart disease. The pancreas produces more and more insulin until it can no longer produce enough to support the body’s demand, will lead to rise of blood glucose resulting to type 2 diabetes.
2. Adult-onset diabetes (T2DM)- People with apple-shaped body or central obesity or excess fat around the middle are at risk of developing Type 2 Diabetes Mellitus.
3. High blood pressure- An increase in weight gain may also lead to hypertension.
4. High cholesterol
5. CVA (Cerebrovascular accident)/ stroke
6. Heart attack
7. CHF
8. Cancer
9. Gout and arthritis/osteoarthritis
10. Sleep apnea
Causes:
1. Overeating and physical inactivity. When the calorie intake is greater than the amount expended, a person gains weight.
2. Genetics and Leptin deficiency. Leptin is a hormone produced in fat cells and placenta; it signals the brain to eat less when body fat is high.
3. Slow metabolism.
4. Psychological factors like binge eating in response to stress and boredom
5. Medications like antidepressants, anticonvulsants, OCPs, corticosteroids, etc.
6. Diseases like hypothyroidism, insulin resistance, polycystic ovary syndrome and Cushing’s syndrome
Weight loss plans and their roles in fighting obesity:
1. Exercise – Physical activity will help burn calories, depending on the type, duration and intensity of the activity. Advantages include improved blood sugar control, cholesterol and blood pressure controls and reduced risk of heart disease.
To lose one pound 3,500 calories should be burned.
2. Diet – Eating fewer calories will stop further weight gain. Diet should be balanced inorder that the nutritional needs of the body are still met when trying to lose weight.
3. Medication - Should be only be used by people with health risks related to obesity. Currently, Orlistat is the FDA-approved medication for weight loss.
Orlistat
Prevents the breakdown of fats so that the body cannot absorb them. The undigested fat then passes out of the body in bowel movement.
Adverse Effects: Flatulence, Fatty/oily stool, Increased defecation, Reduced absorption of fat-soluble vitamins and beta-carotene
Dosage: A capsule 30 mins before a fatty meal. No need to take if the meal is without fat.
Natural Products for Weight loss:
Green Coffee Bean- active substance is Chlorogenic acid. Dosage for weight loss is 80-100mg per day.
Gymnema sylvestre - decrease the absorption of sugar from the intestines.
Tonalin – The active substance is CLA (conjugated linoleic acid) which comes from safflower oil. It works by blocking the enzyme lipoprotein lipase to prevent storage of fats in fat cells and activates the muscles to burn fats.
L-Carnitine- assists in fat metabolism and makes fatty acids available in the muscle tissues to promote energy and endurance.
Green tea – contains flavonoids for antioxidant support.
Underweight
BMI under 18.5 is considered underweight.
Health risks of being underweight:
1. Disruption of hormones regulating menstruation and fertility
2. Low immunity
3. Trouble regulating body temperature
4. Nutritional deficiency leading to problems with heart and lung function, digestion,etc
5. Risks of infection
6. Hair loss
7. Anemia
8. Bone thinning (osteoporosis)
9. Irritability, depression and social withdrawal
10. Less energy
Causes of weight loss (not intentional weight loss):
1. Genetics
2. Fast metabolism and/or hyperthyroidism
3. Eating disorder like anorexia nervosa (may or may not be intentional)
4. Diabetes, depression, digestive diseases/celiac disease or cancer
Anorexia nervosa is a psychological disorder characterized by an out-of-control dieting even if the person is underweight. Because of restriction of food intake, the nutrients required are not met resulting to excessive loss of weight. Complications may lead to heart-rhythm disturbances, digestive abnormalities, bone density loss, anemia, and hormonal and electrolyte imbalances.
Celiac disease is an immune allergic response to gluten which will eventually damage the linings of the stomach (villi) preventing the absorption of nutrients from foods. This also results to malnutrition and weight loss.
Ways to increase weight:
1. Increase calorie intake, should be more than the what the body expends everyday
2. Eat more high-fat foods that are rich in monounsaturated fats which is present in avocado and coconut oil and olive oil
3. High protein diet to increase muscle mass
4. Exercises and weight lifting to gain muscle mass
- Course creator: Lurdes Pastor
- Course creator: Eliana Sequeira
- Course creator: Molly WONG