Chapter Twenty UNCONVENTIONAL DIETS Flashcards
What was the initial reaction to a high-fat, high-protein diet unrestricted in calories?
It seemed to oppose the prevailing theory of obesity and principles basic to biological sciences
Alfred Pennington noted the puzzlement it produced, which stimulated thought on the matter.
According to Jane Brody, what helps people lose weight on a high-fat, high-protein diet?
Elimination of many carbohydrate-rich foods, leading to fewer calorie consumption
Foods like bread, pasta, and sugary drinks are typically eliminated.
List the three kinds of writers of news according to A. J. Liebling.
- The reporter, who writes what he sees
- The interpretive reporter, who writes what he sees and its meaning
- The expert, who writes what he construes to be the meaning of what he hasn’t seen
What issue does the conflict between expertise and observational evidence present in the science of obesity?
Experts’ opinions often overshadow eyewitness testimony from those with weight problems
The assumption that obesity is a psychological disorder affects credibility.
What was Blake Donaldson’s conclusion regarding fatty meat in treating obesity?
Fatty meat should be the essential part of any reducing routine
This conclusion was based on discussions with anthropologists about prehistoric diets.
What dietary regimen did Donaldson prescribe to his obese patients?
Half-pound of fatty meat per meal, prohibiting sugar, flour, alcohol, and starches
Allowed a small portion of raw fruit or a potato daily.
What was the average weight loss experienced by patients on Donaldson’s diet?
Two to three pounds a week without experiencing hunger
Donaldson attributed non-weight loss to ‘cheating’ due to addiction to starches.
How did Pennington’s experience with Donaldson’s diet impact his practice?
He began prescribing the diet to his patients after personal success
Pennington had worked for E. I. du Pont de Nemours & Company.
What were the results of Pennington’s diet trial among DuPont executives?
Executives lost between nine and fifty-four pounds, averaging nearly two pounds a week
They reported a lack of hunger and increased energy.
What was JAMA’s stance on Pennington’s high-fat diet?
They claimed calorie restriction was the only legitimate way to induce weight loss
They warned that the high-fat diet could increase weight and health hazards.
What did George Thorpe argue about semi-starvation diets?
They inevitably fail because they lead to wasting of all body tissues
He experienced rapid weight loss without hunger on Pennington’s diet.
What did the first confirmation of Pennington’s diet come from?
Observations by dietitians Margaret Ohlson and Charlotte Young
They published their findings in the Journal of the American Dietetic Association.
Fill in the blank: According to Pennington, patients experienced increased _______ and sense of well-being.
physical energy
True or False: The Lancet initially supported Pennington’s high-fat diet.
False
They initially dismissed it, claiming low-calorie intake was the best way to restore body composition.
What was the calorie limit set by Ohlson’s version of Pennington’s diet?
Fourteen to fifteen hundred calories a day
This diet consisted of 24% protein, 54% fat, and 22% carbohydrates.
What were the results of Ohlson’s initial low-fat diet trial on four overweight young women?
Zero, six, seven, and seventeen pounds lost
Subjects reported a lack of ‘pep’ and were conscious of being hungry.
In Ohlson’s trial, what was the average weight loss for women on the carbohydrate-restricted diet?
Almost three pounds weekly
Compared to a half-pound a week for the low-fat diet.
What did Ohlson’s subjects report regarding their feelings on the high-fat, low-carbohydrate diet?
A feeling of well-being and satisfaction; hunger was not a problem
What did Ohlson observe about the body composition of her subjects on high-fat diets?
They appeared to add muscle or lean-tissue mass
This was contrary to expectations from low-protein and balanced semi-starvation diets.
What was the average weight loss for Charlotte Young’s subjects on Ohlson’s diet?
Nearly two pounds per week
Subjects reported not feeling hungry during the diet.
What significant outcome did Young report from her trial with male students?
Average weight loss of almost three pounds each week
Weight loss exceeded expectations based solely on calorie reduction.
What type of trials were Ohlson’s and Young’s studies lacking?
Randomized, well-controlled trials
Needed to establish diet efficacy in extending life or preventing chronic disease.
What did William Leith find in his clinical experience with Pennington’s diet?
Satisfactory weight loss may be accomplished by a full caloric, low carbohydrate diet
Patients ingested protein and fat as desired.
What was a common belief among nutritionists about weight-reducing diets until recently?
They were not worth testing
Focus was on physiological and psychological abnormalities related to obesity.
What did clinical investigations report about high-fat, carbohydrate-restricted diets?
Weight losses of between one and five pounds a week
Subjects did not report symptoms of semi-starvation.
At what caloric intake did Wilder treat his obese patients?
80–100 calories’ worth of green vegetables along with a very low-calorie diet
Patients reported a remarkable absence of hunger complaints.
What did Bistrian and Blackburn report about their patients on a high-protein, high-fat diet?
Patients lost forty-seven pounds on average over four months
Nearly three pounds a week, with patients loving the diet.
What was the outcome of the study conducted by Peña and colleagues on obese children?
Children on the carbohydrate-restricted diet lost almost twice as much weight
Compared to those on a semi-starved balanced diet.
What hypothesis did Robert Kemp develop regarding carbohydrate tolerance?
The degree of tolerance for carbohydrate varies from patient to patient
This led him to create a carbohydrate-restricted, calorie-unrestricted diet.
How many patients were successfully reduced in Kemp’s practice?
More than seven hundred (49 percent)
Defined as having lost more than 60 percent of their excess weight.
What was the renewed interest in testing carbohydrate-restricted diets attributed to?
Rising obesity levels and questioning of prevailing weight loss wisdom
Led to independent trials comparing low-fat diets with Pennington-type diets.
What was a common result across multiple trials testing low-fat semi-starvation diets?
Weight loss after three months was consistently reported
Specific results varied, but significant weight loss was observed.
What did the six independent teams of investigators set out to test?
Low-fat semi-starvation diets versus ‘eat as much as you like’ Pennington-type diets.
What was the outcome of the trials comparing low-carbohydrate diets to calorie-restricted diets?
Weight loss was two to three times greater on the low-carbohydrate diet.
What conclusion did the 2003 article by seven physicians from Yale and Stanford reach about carbohydrate-restricted diets?
The evidence was insufficient to recommend or condemn these diets.
What average weight loss was reported from lower-carbohydrate diets when carbohydrates were restricted to less than sixty grams a day?
An average of thirty-seven pounds.
What is a common assumption about weight loss that needs to be overturned?
That a calorie is a calorie.
What did Fred Stare claim about calories?
Calories are all alike, regardless of their source.
What happens to weight loss when carbohydrates are restricted, even with high caloric intake?
Significant weight can be lost, independent of calorie consumption.
What did Bistrian and Blackburn find about their patients eating only lean meat, fish, and fowl?
Half of them lost at least forty pounds each.
What is the success rate of a balanced semi-starvation diet according to Bistrian?
One percent.
What is a key reason for the failure of balanced semi-starvation diets?
Hunger.
What did Peña and Leith believe about carbohydrate-restricted diets?
They were more successful because patients could eat whenever hungry.
What was the effect of an 1,800-calorie carbohydrate-restricted diet according to Per Hanssen?
It was likely to make weight maintenance easier than a 900-calorie balanced diet.
What did Bistrian say about the hunger levels at 650 to 800 calorie intake?
They were able to reduce or eliminate hunger.
What is the implication of adding carbohydrates to a diet according to Drenick’s observations?
It leads to overwhelming hunger.
What did Walter Bloom note about starvation therapy for obesity?
Total starvation and carbohydrate restriction have much in common.
According to Keys, what happens to the sensation of hunger during total starvation?
It disappears in a matter of days.
What did Drenick find about the experience of prolonged starvation?
It was tolerated easily by patients.
What critical factor is questioned in weight loss diets?
The presence or absence of carbohydrates.
What did Alfred Pennington describe regarding diets rich in fat and protein?
They provoke paradoxes in weight management.
What was Johanna Dwyer’s explanation for weight loss on low-carb diets?
Individuals reduce their energy intakes by as much as 30%.
What did the AMA Council on Food and Nutrition concede about low-carbohydrate diets?
Weight loss on these diets does not refute calorie restriction as the only way to lose weight.
What is the argument regarding the effectiveness of carbohydrate-restricted diets?
They are explained as calorie-restricted diets in disguise.
What did Jean Mayer note about bread in a low-fat reducing diet?
Bread has about sixty calories a slice.
What did John Yudkin propose about carbohydrate-restricted diets?
Removing carbohydrates will also reduce fat calories.
What conclusion did Yudkin reach in his 1960 Lancet article about high-fat diets?
High-fat diets lead to weight loss despite unrestricted fat and protein allowances.
What did Yudkin confuse in his conclusions about weight loss?
Association with cause and effect.
What was Yudkin’s conclusion about high-fat diets?
High-fat diets lead to weight loss because they are low-calorie diets despite unrestricted fat and protein intake.
Yudkin suggested that weight loss was associated with calorie restriction, not necessarily caused by it.
What common finding occurs in studies of carbohydrate-restricted diets?
Subjects often reduce their calorie consumption on carbohydrate-restricted diets.
This does not imply that the calorie reduction is the cause of weight loss.
What did Weldon Walker and Sidney Werner report about weight loss?
Subjects lost significant weight while consuming 2700-2800 calories a day.
This indicates that weight loss can occur even with higher calorie intake.
What calorie intake is often believed necessary for significant weight loss in obese patients?
Typically 1200-1500 calories, or even 800 calories or less.
Clinicians traditionally use these low-calorie diets to achieve weight loss.
What is the paradox regarding appetite and carbohydrate-restricted diets?
Individuals on carbohydrate-restricted diets often experience less hunger despite potentially consuming fewer calories.
This raises questions about the mechanisms behind appetite suppression.
According to Ancel Keys, how does hunger manifest in a carbohydrate-rich diet?
Subjects experience a persistent clamor of hunger on carbohydrate-rich diets.
This contrasts with the expectations for those on a high-protein, high-fat diet.
What did Richard Spark suggest about ketone bodies?
Ketone bodies produced during carbohydrate restriction can suppress appetite.
However, this explanation is questioned due to inconsistent evidence.
What did Ernst Drenick find regarding hunger sensations and ketone bodies?
Hunger sensations often disappeared before ketone bodies could be detected in subjects’ blood.
This suggests that appetite suppression may not be directly related to ketosis.
What is a common explanation for reduced hunger on high-fat, high-protein diets?
Fat and protein digest slowly, making individuals feel satisfied longer.
This leads to less frequent hunger compared to carbohydrate-rich diets.
What fundamental premise did Alfred Pennington adopt from homeostasis research?
The relationship between fuel supply and demand at the cellular level determines hunger and energy expenditure.
This perspective shifts focus from calorie counting to metabolic needs.
What observation did Hugo Rony make about obese individuals?
Obese individuals often spend much of their life in energy balance, similar to those of normal weight.
Their caloric intake is regulated by their body’s energy needs.
What happens to metabolism when obese individuals consciously try to eat less?
Their metabolism and energy expenditure decrease.
This response is similar to that of lean individuals under calorie restriction.
What did DeWitt Stetten suggest about fat release in obese mice?
The rate of fatty acid release from fat deposits is significantly slower in congenitally obese mice compared to lean mice.
This could explain why obese individuals do not lose weight even with adequate caloric intake.
True or False: The American Medical Association claimed that weight loss cannot occur with high-caloric intake.
True.
This reflects the conventional belief in calorie restriction as essential for weight loss.
Fill in the blank: The argument that carbohydrate-restricted diets work by the same mechanism as _______ diets is debated.
calorie-restricted.
This highlights the complexity of understanding appetite and weight loss mechanisms.
What did Pennington propose causes obesity in humans?
A metabolic defect that slows down the release of fat from adipose tissue.
According to Pennington, how does adipose tissue contribute to obesity?
It accumulates fat calories after meals but doesn’t release them quickly enough to meet cellular needs.
What is the law of energy conservation as it relates to obesity?
If energy enters fat tissue faster than it exits, fat storage increases.
How does Pennington explain the relationship between appetite and fat accumulation?
Fat calories not available to cells lead to increased hunger and decreased energy expenditure.
What is the compensatory mechanism that occurs in obesity according to Pennington?
Adipose tissue expands to release fat more effectively, creating a new energy balance.
What happens to energy expenditure when calorie intake is restricted in obese individuals?
Energy expenditure decreases due to the body conserving energy.
Fill in the blank: Pennington believed that removing _______ from the diet could correct obesity.
carbohydrates
What did Pennington suggest as a more rational form of treatment for obesity?
Increasing mobilization and utilization of fuel by the muscles and organs.
What is the expected effect of a high-protein, high-fat, carbohydrate-restricted diet on fat metabolism?
It would correct the metabolic fault and lead to a decrease in adipose tissue.
True or False: Pennington believed that calorie restriction is necessary for weight loss on a carbohydrate-restricted diet.
False
What effect does Pennington theorize carbohydrate restriction has on metabolic rate?
It increases metabolic rate and physical activity.
According to Pennington, how do laboratory animals adjust their food intake?
In response to available calories, they increase or decrease their food intake.
Fill in the blank: Pennington speculated that obesity was caused by an inability to metabolize _______.
pyruvic acid
What observation did Du Bois and his colleagues make regarding metabolism on a meat diet?
Participants increased their basal metabolic rate while losing weight.
What was the main observation about obese patients’ caloric intake according to Pennington?
Some can maintain weight on a surprisingly low caloric intake due to metabolic defects.
What did Pennington conclude about the relationship between fat calorie mobilization and appetite?
Increased fat mobilization leads to a decrease in appetite.
What did Pennington’s hypothesis of obesity help explain about sedentary behavior?
It explains why obese individuals tend to be less active due to energy conservation.
True or False: Pennington’s theories were widely accepted and tested during his time.
False
What did Pennington believe about the flow of fat from adipose tissue?
It should be increased to maintain a healthy equilibrium between fat storage and release.
What dietary approach did Ohlson modify in her version?
Ohlson included more milk, cheese, and eggs than Pennington had recommended
Ohlson aimed to meet the recommended daily allowances for essential vitamins.
What did Ohlson expand in her diet?
The choice of fruits and vegetables
Ohlson worried about the monotony of large servings of meat.
What issue did the AMA’s 1973 critique overlook regarding weight-loss diets?
The issue of hunger
The critique included ‘anorexia’ as a side effect, which is a technical term for loss of appetite.
What was reported about the diet by William Dietz in 1989?
It was ‘especially successful’ on obese patients with Prader-Willi syndrome
This syndrome is characterized by ravenous appetites that appeared to be suppressed by the diet.
What was the average weight loss for carbohydrate-restricted diets compared to higher-carbohydrate diets?
Eight pounds for carbohydrate-restricted diets and four for higher-carbohydrate diets
This was based on randomized control trials.
What critical assumption did Yudkin make in his conclusions?
He assumed three-day dietary records could be extrapolated to the entire two weeks of the study
Three-day dietary records are notoriously inaccurate.
Fill in the blank: Drug studies were encouraged by the relative ease of obtaining money and resources from the _______.
[pharmaceutical industry]
Who noted that the diet was particularly effective for patients with a specific genetic disorder?
William Dietz
He serves as director of the Division of Nutrition and Physical Activity at the CDC.
What did Ted Van Itallie say about Jean Mayer’s attention to prewar German literature on obesity?
Mayer hated the Germans
Van Itallie mentioned that Mayer shot a few Germans in World War II.
What was a concern Ohlson had regarding the original diet recommendations?
The diet did not meet the recommended daily allowances for essential vitamins
This led her to adjust the diet by adding more dairy and expanding fruit and vegetable options.
True or False: The average weight loss for higher-carbohydrate diets was greater than for carbohydrate-restricted diets.
False
The average weight loss was greater for carbohydrate-restricted diets.
