Advanced Healing MethodsGCU Holistic Health
Fall 2009
Obesity
Surgeon General: “Overweight and obesity result from excess calorie consumption and/or inadequate physical activity.”
US, 1970’s to 1990’s: increased caloric intakeNHANES- 1971 to 2000- 150 calories per day in men,
350 in womenUSDA- 1971 to 1982: 3300 calories per day per person
1993-1997: 3800 calories 90% of the 500 calories from carbs
The rise in obesity also coincides with increasing exercise
The Pima IndiansHighest rates of obesity and diabetes in the
USNIH: “As the typical American diet became
more available on the reservation after the war (WW II), people became more overweight.”“If the Pima Indians could return to some of
their traditions, including a high degree of physical activity and a diet with less fat and more starch, we might be able to reduce the rate, and surely the severity, of unhealthy weight in most of the population.”
The Pima IndiansEarly 19th century and before
Game, fish, clams, corn, beans, cattle, poultry, wheat, melons, figs, cactus
1846: “Sprightly… in fine health… the greatest abundance of food”
1860’s: “Years of famine” as white and Mexican settlers came in
Game hunted nearly to extinction, water taken by the whites1890’s: government rations to avoid starvation1900’s: “Real obesity is found almost exclusively
among the Indians on reservations”The rations- 50% of calories from sugar and flour
1950’s: “large quantities of refined flour, sugar, and canned fruits high in sugar,” also soda, candy, chips, cakes
1962: “soda pop is used in immense amounts”
Energy BalanceFirst Law of Thermodynamics
A calorie is a calorie, calories in = calories outChange in energy stores = energy intake –
expenditureWeight gain accompanied by positive energy balance
But not necessarily caused by itTwo possibilities
Overeating and inactivity cause obesity “Willful descent into self-gratification”
The obese responsible for their condition Character defect- they overeat and won’t change Willpower is the cure
Like alcoholism from overdrinkingMetabolic imbalance induces overeating and
inactivity, resulting in obesity
Energy BalanceDiseases of civilization associated with obesity2 hypotheses
Obesity causes or worsens the conditions of metabolic syndrome and the diseases of civilization And obesity caused by overeating, particularly a high-
fat diet, and inactivity, so low-fat diet to fixThe same metabolic imbalance that drives us to
fatten also causes metabolic syndrome and the diseases of civilization
Hormonal (metabolic) effects on weightPositive caloric balance in children
Eating because they’re growing- hormone-drivenWeight gain in pregnancy hormonalHeight genetic and driven by hormonesAll of these induce a positive caloric balance
The Low-Fat DietLow-fat, high-carb diets recommended for weight
lossFats fatten us the most effectively (in this view)
EvidenceAssociation between CVD, DM, and obesity
If high-fat diets cause CVD, and if CVD, DM, and obesity move together in populations, then the high-fat diet causes all three
But there is no strong evidence for this!Rats become obese on a high-fat diet
But only susceptible strains- others don’t And even these will grow fatter on high-fat, high-carb than
on high-fat, low-carb And rats will also fatten when fed sugar As will other animals, like pigs (who digest most like humans) Rats get obese on unlimited grocery food
But they choose the high-carb food, not the high-fat, low-carb food
The Low-Fat DietLow-fat, high-carb diets recommended for weight lossEvidence
The density of fat cals fools people into eating too many Fats have 9 calories/gram, while carbs (and proteins) have 4 apiece
So eating the same amount of food as fat rather than carbs results in increased calorie intake
Theory- we match intake to output by simple mechanisms like limiting the volume of food intake So fiber-rich veggies fill our stomachs with indigestible cals
But- rat diets diluted with water, fiber, and clay Rats keep eating until they get their usual caloric intake 90% of daily cals put into stomachs, and they stop eating
But not when water put in Rats adjusting intake in response to calories, not volume,
mass, or tasteSo- obesity as a defect of behavior ?
Hunger and satiety dissociated from underlying metabolism That hunger might be a communication from the body
about underlying conditions is rarely considered
StudiesLow-cal semi-starvation
diets “Balanced” diets with fewer
caloriesBenedict 1917
2 groups of 12 men, 1400-2100 calories per day, 3 mos
Weight loss Constant hunger, feeling
cold Metabolism slowed 30% Anemia, weakness, loss of
concentration, loss of libido Weight gain on any more
than 2100 cals Binge eating after study,
all weight regained in 2 weeks And another 8 lbs extra in the
next 3 weeks In general- 25% lost 20 lbs,
5% lost 40 lbs Almost all gained it back
Keys 1944 32 male conscientious
objectors 24 weeks on “semi-
starvation” diet- 1570 calories 400 cals protein, 270 fat, 900
carbs Also 5-6 mile walk each day 12 lbs lost in 12 weeks
Another 3 the next 12 weeks Slow nail growth, hair loss,
increased wound healing time, metabolism down, slowed reflexes, depression, irritability, feeling cold
Constant hunger, fixation on food, cheating on diet
When allowed to eat, 8000 cals per day
Total weight gain 10 lbs
ExerciseJean Mayer, 1950’s- inactivity causes obesity
But correlation is not causationTwo questionable studies, never replicated
“J. Mayer has since demonstrated, in both animal and human studies…” -J. Mayer
Or… exercise burns calories but stimulates appetite“Consistently high or low energy expenditures
result in consistently high or low levels of appetite.” Hugo Rony, 1940
1998: “Energy intake can be interpreted as a crude measure of physical activity.”
ExerciseBjörntorp 1973- 7 subjects, 6 months of exercise three
times a week, no change in weightPi-Sunyer 1989- weights can go up, down, or remain
steadyDenmark 1989- sedentary people trained to run
marathons for 18 months18 men lost 5 lbs, 9 women lost no weight
Randomized trials show less effectSomewhere between 3 ounces a month gained and 2
ounces a month lostAnimal experiments- the more the rats run, the more
they eat, weights unchanged In hamsters and gerbils, voluntary running produced
increases in body weight and body fatHunger increases in proportion to the calories
expended“Working up an appetite”
Fattening DietsTo fatten- excess calories have to be stored as fat
Not stored as muscle, not burned in metabolism or physical activity
Continuing excess calorie consumptionMassa tribe- Cameroon- fattening ritual
Normally- milk as staple, 2500 calories per day To fatten- milk with sorghum porridge, 3500 cals/day Typical gain 15-20 lbs. Fattening by adding carbs
Sumo wrestlers Normal Japanese diet 2300 cals/day Upper group- 5500 cals/day, 57% carbs, 16% fat Lower group- fatter, less muscular
5100 cals/day, 80% carbs, 9% fatOverfeeding studies- 10,000 calories of mostly carbs a day,
but hunger late in the day
Reducing DietsAHA- carb restriction today is a “fad diet”
But this was the standard medical treatment for obesity through most of the 20th century- p. 314
The AHA recommended high-carb, low-fat diets for CVD in the 1960’s, then for obesity, and low-carb diets were marginalized
Observation- the obese eat more carbsDenmark 1936
21 obese patients, 2 years1850 calories/day, 25% carbs, 60% fat
Cream, butter, olive oil, eggs, cheese, meat 2 lbs weight loss per week, no chronic hunger or
fatigue
Reducing DietsDonaldson 1920’s: 6 oz meat, 2 oz fat, at each
meal, no sugar, flour, alcohol, starch, ½ hour walk17K patients, 2-3 lbs/wk loss, no hunger
Alfred Pennington- DuPont 1949: 20 execs, 9-54 lbs loss, 2 lbs/wk, no hunger, increased physical energy and sense of well-beingNo calorie restriction- min 2400, avg 3000Carbs restricted to 80 cal/meal
JAMA and Lancet: “Freak Diets!” (p. 331)Thorpe 1957- rapid weight loss (6-8 lbs/mo), no
hunger, weakness, lethargy, or constipation
Reducing DietsOhlson and Young 1952: 14-1500 cals/day, 24%
protein, 54% fat, 22% carbs7 women, overweight to obese, 16 weeks, 19-37 lbs lost
No hunger, addition of muscle mass16 overweight women, 9-26 lbs lost in 10 weeks, no
hunger, “unexpectedly healthy,” sense of well-being8 overweight male students, 1800 cals/day, 9 weeks,
13-28 lbs lost, almost 3 lbs/weekLeith 1961: 48 patients who had tried and failed with
low-cal diets, 28 lost btw 10 and 40 lbs“The patients ingested protein and fat as desired”
Reducing DietsWilder 1930’s: a few hundred cals/day, meat, fish, egg white,
80-100 cals of green veggies- weight loss without hungerBistrian 1970’s: 700 patients, 50% fat, 50% protein, 650-800
cals/day, weight loss without hunger1000, 1200, 1320, 1400, 1800, 2200, 2700, or no calorie
restriction at all- weight loss without hungerKemp 1956: low-carb diet, no calorie restriction
1450 overweight and obese patients 49% lost at least 60% of excess weight- 25# after 1 year 38% defaulted, 13% didn’t lose weight
Carb restriction usually does a lot better than low-cal “balanced diet” when compared directly, even when the low-carb diet has more calories- p. 337
6 recent trials- weight loss after 3-6 mos was 2-3x greater on low-carb, calorie-unrestricted diet than on calorie-restricted, low-fat diet
JAMA 2003: “Greater weight loss than higher-carbohydrate diets” 37# vs. 4#, p. 339
Reducing Diets“If the Pima Indians could return to some of their
traditions, including a high degree of physical activity and a diet with less fat and more starch, we might be able to reduce the rate, and surely the severity, of unhealthy weight in most of the population.”
Obesity is a “penalty for living off the fat of the land rather than the carbohydrate”
But- start with an 800-calorie fat and protein dietAdd 400 more calories of fat and protein for a low-carb
weight loss dietAdd 400 carb calories, though, and get a “balanced”
low-cal semi-starvation diet50X less effective for weight loss
Reducing DietsLow-carb diets
One fear is that the brain needs glucose130 grams of carb the “minimum safe levels”But if there’s less than 130 g, the liver makes
ketone bodies to supply brainAnd if no carbs at all, 75% of CNS fuel from
ketones The rest from glucose made from amino acids or glycerol Protein from diet or muscle
Ketosis- normal- 5-20 mg/dl in 5-10% carb diet Diabetic ketoacidosis- pathological- 200 mg/dl
Reducing DietsV. Stefansson- early 20th century
Lived with the Inuit for 10 years eating only meat He and the Inuit were vigorously healthy So is the Inuit diet balanced?
Conventional wisdom- balanced diet the bestNeed carbs for brain glucoseAnd to prevent deficiency diseases
Deficiency diseasesScurvy- vitamin CPellagra- niacin (vit B3)Beriberi- thiamine (vit B1)Rickets- vitamin DAnemia- iron, vit B12, folateFresh fruits and veggies to prevent
Reducing DietsAll-meat diets considered unhealthy
Raise BP, cause goutMonotonousDeficiency diseasesKidney damage
1928- Stefansson and AndersonAte only meat for an entire year
79% fat, 19% protein, 2% carb (glycogen in muscle)Ketone bodies in urine to rule out carb cheatingBoth in good condition afterward
6 and 3 lbs weight loss, BP decrease, no kidney damage, no gout, no vitamin or mineral deficiencies, a case of gingivitis cleared up
Reducing DietsDeficiency diseases
Studies all done with high-carb diets low in meat and dairy- p. 321
Meat contains all essential amino acids And 12 of 13 essential vitamins All in large quantities and in high-utility forms
Vitamin C- only small amounts in meat So scurvy can be cured by adding fruits and veggies But this doesn’t mean that the lack of these causes it! Inuit- no fruits, no veggies, no scurvy Could it be that carbs, esp refined carbs, increase
our need for vitamins?
Reducing DietsDeficiencies
B vitamins depleted by carbs in dietVitamin C also
30% lower levels in type 2 DM Lower vit C in metabolic syndrome too Vitamin C deficiency as a disease of civilization?
Mechanism- “biologically plausible and empirically evident” High blood glucose and/or high insulin increase the
body’s requirements for vitamin C Vit C similar structure to glucose, transported into the cells by
the same insulin-dependent mechanism Glucose and vit C compete, glucose greatly favored So vitamin C uptake inhibited in high blood glucose Glucose also impairs kidney reabsorption of vit C Insulin infusions also cause vit C levels to fall So… carbs flush out the vitamin C and inhibit us from
using it So absence of fruits in scurvy, or presence of refined carbs?
Energy BalanceChange in energy stores = energy intake –
expenditureAssumption- intake and expenditure are
independent variablesWe can change one without changing the otherUSDA- “For most adults a reduction of 50 to 100
calories per day may prevent gradual weight gain.”But- homeostasis- energy regulation involuntary
Our bodies minimize long-term fluctuations in energy reserves and maintain a stable weight Unless the set point is changed
Energy BalanceSet-point hypothesis
Energy intake and expenditure are dependent variables Physiologically linked
Energy storage determined biologically- p. 299 Interaction of genetics and environment
Any increase in energy expenditure induces hunger and increase in intake
Any decrease in intake induces decrease in expenditure Slower metabolism or reduced activity Lean people are more active because more of the energy
they consume is available as energy, less stored as fat- determined on a cellular or hormonal level
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