*Don’t need to know exact percentages (i.e.: know that more women than men are on diets, more boys than girls are obese)
Obesity is a health hazard of epidemic proportions in most developed countries.
The WHO estimates 35% of the adult population in industrialized nations are obese.
The Public Health Agency of Canada: 25% of Canadian adults and nearly 10% of teenagers (12-17) are obese.
30% of Canadian adults and teens are overweight or obese.
More boys than girls are obese (15.1% vs. 8%).
About 44% of women and 29% of men are on a diet at any given time.
<40$ billion are spent annually trying to lose weight. Total cost to Canadian taxpayers attributed to inactivity is 6.8$ billion
Numerous diseases and health problems are associated with obesity
o Diabetes: a disorder where the pancreas is not producing enough or sometimes not any insulin
o Cancer: many cancers can be prevented by eating healthily and avoiding obesity (exercise)
o Congestive Heart Failure: your heart can’t pump enough blood to your body’s other organs
o Enlarged Heart: the heart muscle becomes larger due to being overworked, which naturally happens if you are
o Pulmonary Embolism: a potentially fatal blockage of an artery; lack of activity can result in an embolism
o Polycystic Ovarian Syndrome: a condition in which cysts develop in the ovaries; these can brust, causing even
o Gastro-esophageal Reflux Disease: stomach acid flows from the stomach back up into the esophagus; common in
o Fatty Liver Disease: is a reversible condition in which large pockets of fat accumulate in liver cells
o Hernia: caused when the hole in the diaphragm weakens and enlarges
o Erectile Dysfunction: the inability to develop or maintain an erection; can be obesity related
o Urinary Incontinence: the inability to control urination; it frequently associated with obesity, weak bladder and
pelvic floor muscles
o Chronic Renal Failure: kidneys fail to work; a greater risk to those who are overweight or obese
o Lymph Edema: results from a damaged or dysfunctional lymphatic system; people suffering from obesity can crush
their own lymphatics
o Cellulitis: is a spreading infection, involving both the dermis and subcutaneous skin tissues, resulting from poor
lymph flow caused by obesity
o Stroke: caused by a lack of blood to the brain
o Pickwickian Syndrome: characterized by sleep apnea resulting from obesity placing an excessive load on your
o Osteoarthritis: a clinical syndrome in which low-grade inflammation results in joint pain; it is caused by abnormal
wearing of the cartilage, oftentimes due to obesity
o Depression: can be worse in those with a weight problem
o Gout: occurs when uric acid accumulates in the blood; nerve endings become irritated, causing extreme pain; it is
made worse by carrying extra weight
o Gallbladder Disease: commonly affects overweight people as a result of high blood cholesterol levels, which cause
85% of Canadians do not engage in sufficient physical activity. Focus on fitness, not dieting; higher fitness means lower mortality
rates regardless of body weight.
Tolerable weight is a realistic standard that is not ‘ideal’ but is ‘acceptable’; tolerable weight is closer to health-fitness than physical-
fitness standards. Measure your BF% so you have a realistic weight loss goal. About 80% of your ability to achieve an ‘ideal body
weight’ is related to your food choices; exercise may make it easier to make healthy food choices (chain rxn): Exercise helps to enhance the brain’s resources for executive functions like inhibitory control, making it easier for you to
resist unhealthy food.
Exercise also appears to make your brain more sensitive to signs that you are full.
Exercise increases sensitivity to leptin (the ‘satiety hormone’) a hormone released from fat cells that inhibits food intake
Exercise may help control BW by altering the hormones released by the gut after a meal
Exercise group have increased levels of amylin (inhibitory feeding hormone) when a meal was eaten (not going to eat as
When treated with CCK (a gut hormone), which limits meal size, the exercise group decreased food intake more than the
Diets don’t work: Only 10% who begin a diet reach their goal and only 5% keep the weight off. The other 95% regain more fat than
muscle, making it harder to lose weight in the future since BMR decreases and the body becomes more efficient at storing calories
Why diets don’t work:
1. Low calorie diets are low on essential nutrients (iron, Ca, B-vitamins, zinc, etc.) -> low calorie diet weakens the immune
system, making you more likely to get sick.
2. Insufficient calories lead to lack of energy, slower growth and repair, reduced size of muscles and bones
-> light eaters tend to binge; consume more fat calories -> light eaters often sabotage their efforts to stay trim
-> light eaters despite reporting eating fewer calories had huge fluctuations in their weight
-> 30% of light eaters ended up overweight
-> on a crash diet, 50% of the weight loss is LBM (lean body mass = muscle), a lot of the weight that is lost is water too.
-> When the body uses protein instead of fats and CHO for energy, weight loss is 10x faster.
-> First 1-2 weeks of a diet, up to 70% of the initial weight loss is in the form of water as glycogen is burned and released 3-4g of
water for each gram of glycogen (lose up to 3+ pounds), not until 2 weeks into a diet that you start losing fat. Repeated yo-yo dieting
is worse than no weight loss at all.
-> When dieting, the body goes into conservation mode, burning calories more slowly. A low-cal diet makes the body more efficient
at storing fat.
-> After a 10% weight loss the body compensates by burning 15% fewer calories
-> Yo-yo dieting causes the loss of LBM thus BMR is lower and the set point is moved higher, making it harder to lose weight. Also
increases bone loss.
-> On low calorie diets BMR slows by 5-20%
Guidelines: Never <1200 calories/day for women, never <1500 calories/day for men
Dieting makes you feel deprived and depressed, often leading to overeating. -> Diets that remove red meat may leave you feeling
tired, irritable, and anemic.
Alternative views - Myth: fasting tricks the body into ‘starvation mode’. Efficient adaptation to famine allowed survival: lowering
RMR during starvation allowed us to live longer; it doesn’t mean skipping a meal or not eating for 24 hours, needs to be more than
that – lowered RMR due to fasting doesn’t occur until after 60 hours and is only an 8% drop. In fact, during short-term fasting,
metabolic rate increases (increase of 3.8-10% after 36-48 hours of fasting). From an evolutionary perspective, epinephrine and
norepinephrine sharpens the mind and makes us want to move around, encouraging us to seek food (increasing survival). Only after
several days of fasting when energy conservation kicks in (metabolic rate is lowered).
Myth: fasting causes muscle loss. Only in prolonged fasting does protein catabolism become an issue (using muscle as its calorie
source). Protein catabolism occurs when stored liver glycogen becomes depleted; to maintain blood glucose, conversion of amino
acids into glucose must occur.
Genetics : women have a harder time of losing weight than men. Less LBM thus lower BMR.
For species protection, women are more adapted at storing fat; women are more likely to survive in times of famine. Women adjust
energy intake to energy expenditure and energy expenditure to energy intake better than men (women’s body will adjust better
than men’s, will lose less weight). Weight loss in response to restricted energy intake or increased energy expenditure is lower in
women than men. Women have a greater ability to preserve body mass in the face of an energy deficit. Low calorie diets can promote amenorrhea (loss of menstrual cycle) and lead to osteoporosis, dry skin and dull-looking hair.
Stay away from diet traps such as: -eat all you want and still lose weight or -Lose 20 pounds in 2 weeks!
Creeping obesity: being out of balance by just 10-calories a day can lead to a weight gain of 10-lbs/year. As you age and your
activity levels decrease, you must decrease your caloric intake.
At 25, you typically start gaining 1-lb/year -> decrease
caloric intake by 3% each decade after 25 so that by 65
your calorie intake is at least 10% less than when it was at
age 25. If people could better manage their emotion and
portion sizes, overeating would be less likely to occur.
Diet accounts for 80% of the health benefits from a
healthy lifestyle; 20% comes from exercise.
Dr.McGuff: ‘The standard American diet is highly
inflammatory.. I advise people to get their diet straight
and then exercise. … inflammatory diet, in combination
with the acute systemic inflammation that occurs as a
part of the exercise stimulus, can actually be a negative
The connection between fructose, uric acid, hypertension, insulin resistance/diabetes and kidney disease means your uric acid level
can be used as a marker for toxicity from fructose. Dr. Richard Johnson wrote The Sugar Fix. He believes the ideal range for uric acid
lies between 3-5.5 mg per dl; anything above that becomes a risk for diabetes, hypertension, obesity, and fatty liver. If overweight
or obese, it is recommended milk (both pasteurized and raw) be limited as lactose can impair your ability to lose weight.
Weight management tips:
1) Identify problem eating
Record the what, when, and why of food/drink: helps to identify habits!
Studies show recording meals may help you lose up to 5% of your weight
2) Differentiate between hunger and appetite
Hunger = the actual physical need for food, appetite = desire for food (triggered by stress, habit, boredom, depression, and
availability of food, etc.)
Eat only when you have a physical need
Avoid the ‘now I’ve blown it’ syndrome
75% of overeating is caused by emotions
Memory of a food peaks after about 4 bites
3) Meal timing and intake management
Become aware of meal timing and portion size -> don’t skip meals or allow yourself to become too hungry: promotes over-
Graze so you are never hungry; smaller meals (5-8) are more effective than 3 larger meals
If you go more than 3-4 hours without eating, the body goes into survival and metabolism will slow down, storing fat
instead of burning it
Eat! Every time you eat you increase your BMR.
Eat breakfast -> after a night without eating, blood sugar is at its lowest; eating breakfast helps to control weight and improves
concentration (some say skipping breakfast can lead to weight gain) -> studies have shown that eating breakfast can have beneficial effects on: appetite, energy metabolism and insulin resistance.
Women eating a big breakfast lost 21% of BW after 8 months compared with 4.5% for women on low-CHO diet where breakfast was
their smallest meal. Obesity and insulin resistance syndrome rates were found to be 35% to 50% lower among people who ate
breakfast every day compared to those who frequently skipped it. Teenagers tend to be about 5-lbs heavier than their peers if they
Eat breakfast, but avoid eating sugary cereal or refined CHO’s (bagels, pancakes, toast, etc.). It must include a healthy protein, such
as eggs; keep you energized throughout the day. Eat breakfast by 8am or risk high cholesterol and a tendency to eat more
throughout the day. Even 10:30am was shown to be too late for breakfast to be of any benefit. The National Wt Control Registry has
investigated long-term successful weight loss maintenance since 1994, characteristics of successful losers = 78% eat breakfast every
day, 90% exercise on average 1-hr daily.
Thermogenesis: control systems in the body designed to keep us healthy. When and how often you eat determines your
thermogenesis. Those people who at more regular meal patterns have higher metabolism and thermogenesis. They also feel full
quicker. This means a slow, steady burn of food. Has nothing to do with the kind of food you eat, more about timing. Changing the
ratio of fat/protein/CHOs: low-fat diets don’t work, low-carb diets work but they are dan