Chapter 11: Water and the Major Minerals

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10 Outline for today

• Obesity
• Finish set-point theory
• Types of obesity
• Weight loss diets
• Recommendations for weight loss
• Where to Get Reliable Nutrition Information
• Next time ?
• Anorexia, bulimia etc.
• How to determine if what you read and hear is
  credible

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Recap of last lecture

• Fasting
• Energy reserves
• Metabolic adaptation
• Order of loss of body proteins
• Set Point Theory

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Where to Get Reliable Nutrition Information
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Eat all you want!" "Watch the fat disappear!"
"Block the starch and lose weight!"

• These and other similar weight loss claims for
  some dietary supplements can cause "unfounded
  hope" and must be removed from Web sites that use
  them, the Food and Drug Administration warned
  Thursday, April 1. The agency said it sent
  warning letters to 16 Web sites that promoted
  certain products as blocking carbohydrates,
  starch and calories from fat without noting the
  need to make lifestyle changes, like exercising
  or eating a healthy diet.

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Susanne Somers' Get Skinny on Fabulous Food, by
Suzanne Somers

• Before she began penning diet books, the only
  remotely health-related entry on Suzanne Somers'
  resume was an infomercial for a thigh exerciser.
  She brings no nutrition credentials to bear on
  this book, which blames excess fat on the
  tendency of the body's enzymes to "cancel each
  other out." Her solution, a Byzantine process of
  eliminating "Funky Foods" and separating the rest
  into "Somersized Food Groups" for mixing and
  matching, has no nutritional basis.
• Somers maintains that when proteins and
  carbohydrates are eaten together, their enzymes
  "cancel each other out," creating a halt in the
  digestion process and causing weight gain.
• Unfortunately, this reasoning is based on
  assumptions that are completely false. In fact,
  the body contains enzymes that are specifically
  keyed to individual proteins, carbohydrates and
  fats. These enzymes do not "cancel each other
  out," because they remain in different areas of
  the digestive tract.
• Furthermore, if digestion did not occur, the
  resulting lack of protein and carbohydrate
  absorption would most likely result in weight
  loss, not the weight gain Somers' predicts.
  Somers' advice not to drink water with meals
  because it dilutes the digestive juices and slows
  digestion is also without merit from Amer.
  Inst. Of Cancer Research

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• The New Beverly Hills Diet, by Judy Mazel and
  Michael Wyatt
• Ms. Mazel has no health or nutrition credentials.
  Her "New Beverly Hills Diet" is fundamentally
  flawed,. Specifically, two of Ms. Mazel's
  theories about digestion are wrong.
• The premise of her diet is that enzymes found in
  food "activate" the human body. Each of the three
  food groups proteins, carbohydrates and fats
  contain their own set of enzymes to break down
  food so that the body can properly digest it.
• Mazel advocates a practice she terms "Cautious
  Combining." "It is when you eat and what foods
  you eat together that matters," she claims.
  Fruits, for example, contain all of the enzymes
  necessary to break themselves down into
  nutrients, and move quickly through the system.
  Proteins and carbohydrates, however, require
  special enzymes that slow down the process.
  Furthermore, enzymes from one food can't "cross
  over" to work on other food groups.
• These suppositions are incorrect. The enzymes
  necessary for digestion are found within the
  body, not in the foods we eat.
• Mazel also states that fat is just another
  symptom of indigestion, that when food is not
  properly digested, it "causes fatness." In fact,
  quite the opposite is true if foods are not
  properly digested they cannot be absorbed. If
  they are not absorbed, they cannot be metabolized
  into fat or anything else.
• On a more practical level, Mazel encourages
  consuming a single food grapes for example
  for an entire day. This is not only nutritionally
  inadequate.
•   Mazel's plan ends up promoting a wide range of
  fundamentally unhealthy habits. Of equal concern,
  however, are the healthy habits it doesn't
  mention. Mazel, like Atkins, neglects to address
  portion control and serving sizes, concepts
  central to any serious program of long-term
  weight management. Perhaps most puzzling,
  however, is Mazel's silence on the subject of
  exercise. Regular physical activity it crucial
  for losing and maintaining weight, but the
  closest Mazel gets to this topic is her
  admonition to chew food thoroughly.
•   from Amer. Inst. Of Cancer Research

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Set-point theory - contd

• In a study with a small set (12) of identical
  twins forced to eat an extra 1000 kcals a day for
  100 days it was found that some gained only 9
  lbs, whereas others gained 29 lbs
• (also each twin in a pair gained about the same
  amount!).
• (From 3500 kcals equivalent to 1 lb. fat one
  would have expected 28.6 lb. gain.)
• This is only one of several studies which
  indicate that different individuals respond to
  excess calories in different ways.

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Set-point theory

• Both rats and humans, if forced to eat more than
  they want, put on weight, but after being allowed
  to eat what they want, lose the excess.
• If a substantial mass of fat is removed, it is
  followed by excess eating and an increase in the
  remaining fat stores!
• If an obese mouse (due to the ob gene mutation)
  is surgically joined to a normal mouse the former
  will lose weight, presumably due to transfer of
  the hormone leptin from the normal mouse to the
  blood of the obese one.

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Contd

• One well-documented metabolic change on
  weight-loss through dieting is a substantial
  decrease in the resting metabolic rate - this may
  be decreased by as much as 50 - and is thought
  to reflect the body's going into "starvation"
  mode. As a result weight loss drops off
  dramatically since the body is using many fewer
  calories - this is a very strong argument against
  using very low calorie diets (

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Set-point theory contd

• Some types of adipose tissue are known as brown
  fat, due to the color. The color is imparted by
  cells which are very rich in mitochondria. Its
  main function seems to be to produce heat.
• Hibernating animals have large amounts. In
  studies with rats, overfeeding leads to increased
  amounts of brown fat and increased heat
  production.
• For example rats fed 80 excess kcals over
  controls put on only 27 more weight, but
  increased their energy production by a factor of
  two as measured by oxygen consumption.
• Obese rats don't adjust.

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Is this you?

• Much of our eating and drinking is determined by
  social settings and customs, e. g. the stereotype
  of sitting down to watch TV with a bag of chips
  and a bottle of beer (lots of calories - 5 kcals
  per chip, 150 kcals for the beer (180 for a
  typical slice of pizza)).

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Obesity, Weight loss and diets

• The maximum sustainable amount of fat a person
  can lose in a day is about 0.6-0.7 pound. Any
  additional weight lost is water.

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Health problems associated with obesity

• hypertension,
• Type II or non-insulin-dependent,
  (maturity-onset) diabetes,
• heart disease,
• hypercholesterolemia,
• hypertriglyceridemia,
• cancer,
• accidents,
• kidney and gall bladder disease,
• arthritis
• and gout.
• People who are obese are three times more likely
  to have high blood pressure and diabetes

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Key points

• Weight loss (decreased fat) occurs when Cals in
  are less than required for BMR physical
  activity etc.
• Independent of type of diet
• Consumption of Cals is estimated to have
  increased significantly in past 30 yrs, with no
  significant increase in physical activity.
• If fad diets worked we wouldnt have a problem.
• It is possible that some people who become obese
  have mutations in one of the many proteins and
  peptides involved in weight control, and thus
  they do not respond properly.
• It is also likely that the ready availability of
  excess Cals leads to people gaining weight (as
  the rats do), but after a period of excess weight
  their set-points become re-set so that they no
  longer lose the excess weight when on a lower Cal
  diet.

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The need for exercise

• Exercise appears also to be an important
  component. The mechanism by which the body
  controls its weight seems not too function very
  well if the person gets less than some minimum
  threshold of exercise (probably about 1 hr per
  day of exercise (at least 30 min)).
• There is an exceedingly strong correlation for
  children between the number of hours they watch
  TV and obesity obesity increases by 2 for every
  extra hour watched per day!

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Estimation of Body Fat

• Underwater weighing Most accurate
• Fat is less dense than lean tissue
• Fat floats
• Skin calipers
• Electrical resistance

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Body Fat Distribution

• Upper-body (android) obesity
• Associated with more heart disease, Type II
  Diabetes
• Fat affects livers ability to clear insulin and
  lipoprotein
• Encouraged by testosterone and excessive alcohol
  intake
• Defined as waist measurement of 40 in men and
  35 in women

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Body Fat Distribution
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Body Fat Distribution

• Lower-body (gynecoid) obesity
• Encouraged by estrogen and progesterone
• After menopause, upper-body obesity appears
• Less health risk than upper-body obesity

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Overweight and Obesity

• Underweight BMI
• Healthy weight BMI 18.5-24.9
• Overweight BMI 25-29.9
• Obese BMI 30-39.9
• Severely obese BMI 40

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Juvenile-Onset Obesity

• Develops in infancy or childhood
• Increase in the number of adipose cells
• Adipose cells have long life span and need to
  store fat
• Makes it difficult to loose the fat (weight loss)

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Adult-Onset Obesity

• Develops in adulthood
• Fewer (number of) adipose cells
• These adipose cells are larger (stores excess
  amount of fat)
• If weight gain continues, the number of adipose
  cells can increase

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Causes of Obesity

• Genetic factors
• Identical twins raised apart have similar weights
• Genetics account for 40-70 of weight
  differences
• Genes affect metabolic rate, fuel use, brain
  chemistry, body shape
• Thrifty metabolism gene allows for more fat
  storage to protect against famine

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Causes of Obesity

• Environmental factors
• Learned eating habits
• Activity factor (or lack of)
• Poverty and obesity
• Female obesity is rooted in childhood obesity
• Male obesity appears after age 30

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Why Diets Dont Work

• Obesity is a chronic disease
• Treatment requires long-term lifestyle changes
• Dieters are misdirected
• More concerned about weight loss than healthy
  lifestyle
• Unrealistic weight expectations

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• Phony weight-loss patch marketers settle FTC
  charges.
• Marketers of the "Peel Away the Pounds" patch,
  which was widely advertised in infomercials, have
  agreed to settle Federal Trade Commission charges
  that they made false and unsubstantiated weight
  loss claims in violation of the FTC Act.
• The defendants falsely claimed that the
  seaweed-based skin patch causes as much as three
  to five pounds of weight loss per week, and made
  other false and unsubstantiated claims e. g.
  "Simply follow our system Place Pound A Patch on
  your upper body. Then carry on with your everyday
  lifestyle. Every three days peel off the patch
  and watch as you take off the pounds. Replace
  with a new patch and drop more pounds. It's that
  easy."
• The settlement requires the defendants to pay 1
  million consumer redress payment. It contains a
  24.4 million judgment, which is suspended except
  for the 1 million payment, with an "avalanche
  clause" that requires the defendants to pay the
  full amount if they understated their financial
  status.

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Any claims that you can lose weight effortlessly
are false

• .The only proven way to lose weight is either to
  reduce the number of calories you eat or to
  increase the number of calories you burn off
  through exercise. Most experts recommend a
  combination of both.
• Very low-calorie diets are not without risk and
  should be pursued only under medical supervision.
  Unsupervised very low-calorie diets can deprive
  you of important nutrients and are potentially
  dangerous.
• Fad diets rarely have any permanent effect.
  Sudden and radical changes in your eating
  patterns are difficult to sustain over time. In
  addition, so-called "crash" diets often send
  dieters into a cycle of quick weight loss,
  followed by a "rebound" weight gain once normal
  eating resumes, and even more difficulty reducing
  when the next diet is attempted.

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Contd

• To lose weight safely and keep it off requires
  long-term changes in daily eating and exercise
  habits. Many experts recommend a goal of losing
  about a pound a week. A modest reduction of 500
  calories per day will achieve this goal, since a
  total reduction of 3,500 calories is required to
  lose a pound of fat. An important way to lower
  your calorie intake is to learn and practice
  healthy eating habits.

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Beware of the following products that are touted
as weight-loss wonders

• Diet patches, which are worn on the skin, have
  not been proven to be safe or effective.
• "Fat blockers" purport to physically absorb fat
  and mechanically interfere with the fat a person
  eats.
• "Starch blockers" promise to block or impede
  starch digestion. Not only is the claim unproven,
  but users have complained of nausea, vomiting,
  diarrhea, and stomach pains.
• "Magnet" diet pills allegedly "flush fat out of
  the body."
• Glucomannan is advertised as the "Weight Loss
  Secret That's Been in the Orient for Over 500
  Years." There is little evidence supporting this
  plant root's effectiveness as a weight-loss
  product.
• Some bulk producers or fillers, such as
  fiber-based products, may absorb liquid and swell
  in the stomach, thereby reducing hunger. Some
  fillers, such as guar gum, can even prove
  harmful, causing obstructions in the intestines,
  stomach, or esophagus.
• Spirulina, a species of blue-green algae, has not
  been proven effective for losing weight.

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Clues to Fraud

• It is important for consumers to be wary of
  claims that sound too good to be true. When it
  comes to weight-loss schemes, consumers should be
  particularly skeptical of claims containing words
  and phrases like
• easy
• effortless
• guaranteed
• miraculous
• magical
• breakthrough
• new discovery
• mysterious
• exotic
• secret
• exclusive
• ancient

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High protein diets

• A high protein diet can cause the body to lose
  calcium, which can lead to development of
  osteoporosis. Osteoporosis can result in broken
  bones.
• Also ketosis.

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Low carb diets

• The arguments of people that favor quick weight
  loss diets is that if you eat enough protein, you
  will spare your own body protein from being
  broken down and instead will break down your
  body's stored fat.
• It turns out this isnt what happens.

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Low carb diets

• It is important to realize that claims for rapid
  weight loss diets are misleading. For example,
  low carbohydrate diets lead to a loss of several
  (5-10) lbs in the first few days however, very
  little of this is fat. The weight lost comes from
  glycogen, protein, and mostly water! Usually at
  most two pounds of fat is lost in the first week.

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Contd

• Low carbohydrate diets may also lead to
  significant loss of lean tissue (muscles) as the
  body uses amino acids as a source of glucose for
  the brain. This has led to cases of heart
  failure.
• Such diets also raise serum levels of uric acid
  (increases chance of gout), alter electrolyte
  balance leading to heart arrhythmias, increase
  risk of kidney damage, and adversely alter some
  blood lipid levels.

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Liquid protein diets

• Originated in hospitals.
• ( "The Last Chance Diet" a book by the promoter
  of one of these products - a typical rip-off).
  The idea was to have a very low intake of
  calories, mostly from protein. This would spare
  the protein tissue in the body from breaking
  down.
• Over 40 deaths were reported before some of these
  products were banned (probably from mineral
  disturbances).

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Liquid protein diets

• Liquid protein formulations usually contain
  ground-up animal hooves, bones, horns, skin etc.,
  dissolved with the aid of proteases
• often deficient in the essential amino acids and
  vitamins and minerals.
• Harmful effects arise from kidney and liver
  problems, electrolyte imbalance, and dehydration
  among others.

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Lifestyle Vs. Weight Loss

• Prevention of obesity is easier than curing
• Balance energy in(take) with energy out(put)
• Focus on improving food habits
• Focus on increase physical activities

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What It Takes To Lose a Pound

• Body fat contains 3500 kcal per pound
• Fat storage (body fat plus supporting lean
  tissues) contains 2700 kcal per pound
• Must have an energy deficit of 2700-3500 kcal to
  lose a pound per week

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Characteristics of a sound weight loss program

• Nutritional adequacy, Sufficient kcals to
  minimize hunger and fatigue
• Slow weight loss (1-2 lbs/week)
• Plan designed to meet individual needs (food
  preferences etc)
• Plan based on readily obtainable foods, socially
  acceptable
• Eat smaller portions and choose from a variety of
  foods.
• Load up on foods naturally high in fiber Fruits,
  vegetables, legumes, and whole grains.
• Limit portions of foods high in fat dairy
  products like cheese, butter, and whole milk red
  meat cakes and pastries.
• Focus on changing eating habits
• Ample physical activity

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How much to lose?

• Nutritionally adequate diets have at least 1000
  kcals/day. So if we assume a person takes in 1000
  kcals/day we can calculate how much fat they will
  lose.
• Suppose that they are really committed and
  exercise as well as dieting (this is hard because
  on the low calorie diet your body "says" it
  doesn't want to do anything which costs energy).
  So we'll assume the person's energy requirement
  is 2200 kcals/day. This means they will have a
  deficit of 1200 kcals/day, which corresponds to
  approx.1/3 lb of adipose fat. So over a week they
  will lose around 2 lbs of fat!

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Weight cycling - Yo-Yo diets

• This phenomena is observed in animal studies as
  well as with humans.
• Several studies suggest that weight gain occurs
  more readily with repeated cycles of weight loss.

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Why do people who diet rarely succeed in
maintaining a lower weight?

• In addition to the initial weight loss to bring
  the person's weight to the desirable range, the
  biggest problem is then maintaining it there.
  This must involve changes in the person's eating
  habits and exercise patterns. What usually
  happens is weight cycling (or the yo-yo
  syndrome)
• Dieting leads to rapid weight loss, decreased
  BMR, fatigue and decrease in physical activity
  and food craving
• This leads to a return to the former eating
  habits and overeating
• Which leads to rapid weight gain, guilt and shame
• Leading to a new desire to lose weight and the
  restart of the cycle

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Contd

• This cycling leads to effects on the person's fat
  metabolism for example the rate of loss of
  weight on the same diet the second time round is
  lower.
• BMR's appear to remain at a lower level.
• Also body composition changes, during dieting
  both fat and lean tissue are lost, but on regain
  more fat is regained relative to lean tissue.
• Thus repeated cycles actually make the person
  have a higher percent fat!
• In addition some studies indicate an increased
  risk of CVD after weight cycling.

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How some succeed

• Weight-control behaviors of more than 3,000
  American adults who have lost an average of 60
  pounds and have kept it off for an average of six
  years.
• How do they do it?
• These successful losers report four common
  behaviors.
• They eat a low-fat, high-carbohydrate diet,
• They monitor themselves by weighing in
  frequently,
• They are very physically active,
• They eat breakfast. Eating breakfast every day is
  contrary to the typical pattern for the average
  overweight person who is trying to diet.
• Six years after their weight loss, most of the
  registrys successful losers still report eating
  a low-calorie, low-fat diet, with about 24
  percent of calories from fat.
• They also exercise for about an hour or more a
  day, expending about 2,800 calories per week on a
  variety of activities. This is equivalent to
  walking 28 miles a week, or four miles a day.
• More than 70 percent of the registrys weight
  losers became overweight before age 18.