- Email: [email protected]
Food intake and energy expenditure
the illness. Numerous animal studies support the notion that maintenance of intracellular glutamine promotes conservation of muscle protein. Because of the instability of glutamine during heat sterilization and prolonged storage and limited solubility, provision of adequate amounts of free glutamine to injured or critically ill patients represents a severe burden. Dipep tides with a glutamine residue at the C-terminal position are more soluble in water than glutamine alone (L-alanyl-Lglutamine: 568 g/L; glutamine -30 g/L) and sufficiently stable during heat sterilization and prolonged storage. Ornithine
a-ketoglutamte is a fascinating molecule that is a precursor of glutamine and arginine, but also of other amino acids and keto acids that are important in the control of protein metabolism. Ornithine a-ketoglutamte also has a potent secretagogic effect on hormones such as insulin and growth hormone. The last chapters of the section on ammo acid supply in disease deal with amino acid formulas devoted to specific situations. There is a chapter on amino acid support in catabolic illness such as trauma, surgery, inflammation, or infection. Campos and Meguid discuss the
amino acid requirements cial attention
in cancer. Spe-
is paid to the amino acid
solutions used for acute renal failure. Given the range and breadth text, it is most appropriate scientists,
and clinicians
the different
of this
for fellows, interested
in
aspects of amino acid me-
tabolism. Karl M. Nelson Director, office of Research Baptist Health System Birmingham,
AL 35213,
USA
SSDI 1043-2760(95)00200-6
Chewing and the Fat Food Intake and Energy Expenditure Edited by Margriet S. WesterterpPlanteng, Elisabeth W.H.M. Fredrix, and Anton B. Steffens, with Harry R. Kissileff as Editorial Advisor. Ann Arbor, CRC Press, 1994, $49.55 (408 pages), ISBN O-8493-9228-4. This book addresses the relationship between physiological and neurological responses to food, with the intent of providing a fresh understanding of obesity and misregulation of food intake. Unfortunately, the book is an example of good intentions gone astray. The fault can be placed on inadequacy in understanding and presentation, with the end result being a substandard book. The preface, consistent with the rest of the book, informs the reader that this is a textbook for students and that it has incorporated student feedback. The intended audience is students from a variety of academic disciplines that have a need to integrate concepts from among such areas as physiology, biology, psychology, and nutrition. The preface further informs the reader that the material is suitable for advanced investigators in these disciplines. The result serves neither students nor investigators because the book is poorly presented and edited, contradictory in delivery, superficial in topical coverage, and poorly researched. The material is presented in 23 chap ters, distributed among the subdivisions of (I) Psychobiology of Human Food In-
38
take, in five chapters, (II) Physiology and Endocrinology of Food Intake Regulation, in nine chapters, (III) Energy Expenditure, in seven chapters, and (IV) Food Intake, Energy Expenditure and Evolution, in two chapters. The book was developed to provide a cross-discipline linkage for integrated understanding among topics in biological, behavioral, and nutritional sciences at the Open University of the Netherlands. The underlying focus appears to be a rationale for the misregulation of food intake that leads to obesity. The hypothesis is that the misregulation can be found among the interactions of the neuroendocrine system with food intake, and that understanding neurological and hormonal alterations related to abnormal food intake can lead to a more rational approach to treatment of obesity. Obesity is a perplexing problem that has resisted definitive analysis and probably has many different etiologies. Treatment of obesity has not been very successful. Because obesity remains a major medical problem that has a serious impact on health and quality of life through direct association with hypertension, diabetes, cancer, stroke, and heart attacks, it is a subject worthy of further consideration. In simple terms, obesity develops because of an imbalance between energy intake and expenditure, and understanding the regulation of this balance would go along way toward dealing with obesity and its concomitant health problems. The preface to the book indicates that it contains
01996,
Elsevier Science Inc., 1043-2760/96/$15.00
new interpretations and a fresh look at factors that govern the lack of balance in developing obesity. Unfortunately, the goals set forth in the preface are not accomplished in the text. The presentation fails to convince the reader that the goals are attainable, and support for the hypothesis is not evident. The opening five chapters probably did not receive much student input because they are nearly verbatim from essays published in the Annals of the New York Academy of Science. The material is presented without the depth or detail necessary for student understanding and use. An example is the statement that “a simple formula yields the traditional measure of a justnoticeable difference (JND) . . . ,” but the formula, parameters, and limits of usefulness are not provided. The formula for a just-tolerable difference is also not provided. The language is discipline specific and aimed at experts in the field, consistent with its original publication. The language was not adapted for use in a textbook with an intended student audience and, consequently, is inadequate for students or investigators from other disciplines. The true shortcomings of these chapters are a failure to connect them with the apparent goals of the book. Part I deals with the psychology of short-term food intake and with estimating the factors that regulate the starting and stopping of meal eating. Yet, neither single-meal nor single-day eating relates to obesity development, as individuals of normal body fat also overeat, but adjust by undereating. Obesity develops from an ex-
TEM Vol. 7, No. 1, 1996
tended period of energy imbalance. Moreover, food intake and energy balance are not minute-to-minute regulatory processes, but are averages over extended durations. Although the discussion of what controls food intake at a single meal, as well as the initiation and termination of eating, is an important topic, it is interesting that the primary example of a regulatory substance is caffeine, which is not even a nutrient!-the same example that was used in the original essays. The second section is weak on style, presentation, and content. The length could have been greatly reduced if the ideas had been expressed in a straightforward manner. A prominent phrase “in other words” was too frequently used to re-explain a thought and, unfortunately, the second explanation did not always clarify the topic. Presentation alone was not the problem; inconsistencies abound, such as in Chapter 7, where the title promised “Feeding, Digestion, Absorption and Thermic Effect of Food” and yet the “them-tic effect of food” was neither mentioned nor discussed. A second example is energy expenditure, which is divided into three major components in Chapter 12 and into four components in Chapter 16. Inaccuracies are also present. On page 114, it is stated that “All absorbed nutrients reach the liver via the portal circuit . ..‘I and that included lipid. In Chapter 16, the reader is told that the “basal metabolic rate is
best predicted
from the fat-free mass as
this represents
the active cell mass....”
Although picky,
they
these
criticisms
are cited
Fat-free mass is a concept that has been
main problems
replaced with lean body mass. Active cell
thors
mass is a concept addressed
with energy expenditure
cell mass,
by the body
be the
with the book. The au-
have tried to link energy
intake
and have used
6
the physiological monitoring of dietary energy as a control point. These theo-
with this book as a guide for
ries, however, most clearly indicate that the authors have not done their home-
which
is not included.
The
number
of misstatements
through
14 is too great to enumerate.
Problems
may
to illustrate
in Chapters
students abound in the remaining
mate-
rial, and these problems will confuse the student and alienate established investigators. Selected examples follow. Hydrostatic weighing
is stated to be the gold
standard for determining
body composi-
tion, but then is stated to lack accuracy for individuals
with a low body-mass
dex. The latter is justified
in-
because values
obtained for fat mass are concluded to be unrealistically high. No justification for this conclusion
is provided. Further,
hydrostatic weighing is stated to overestimate changes in fat mass during weight loss and then is used to discuss in some detail fat mass loss in changing nutritional conditions. Another example is fiber, where the usual intake is shown as 4 to 7 g/day in one place and 10 to 30 g/day elsewhere. Such information should be edited prior to publication or the differences explained. Similarly, we are informed in one place that the usual energy intake cannot be determined, although elsewhere take is discussed.
the usual energy
in-
work. Dietary energy and energy expenditure are independent processes and are not related via feedback mechanisms. Alteration of food caloric density tends to change the energy intake because volume, rather than nutrient content, controls intake. If dietary energy were monitored, why would people get obese? Why can we overeat and undereat while maintaining body weight? Dr. Flatt has discussed this concept in some detail, and this book does not refer to his work. The authors have put forth a hypothesis based on inadequate knowledge of the relevant literature and have supported the hypothesis with information that is poorly presented. I would not recommend this book. Ronald H. Birkbabn
Departments of Surgery and BiochemistrylMolecular Biology Medical College of Ohio Toledo, OH 43699-0008, USA SSDI
1043.2760(95)00203-O
BOOKS RECEIVED We thank the publishers for sending us the books listed here. Those we deem of interest to our readers will be reviewed. Readers are invited to write book reviews by informing the Book Review Editor of the title and publisher of books you wish to review. Please address all correspondence for book reviews to Lee A. Meserve, PhD, Book Reviews, Trends in Endocrinology and Metabolism, c/o Department of Biological Sciences, Bowling Green State University, Bowling Green, OH 43403-02 12.
TEM Vol.7,No.1,1996
Biochemistry. Fourth Edition. By Lubert Stryer. New York, W.H. Freeman, 1995, $69.95 (xxxiv + 1064 pages), ISBN O-7 167-2009-4. Biochemistry for the Medical Sciences: An Integrated Case Approach. By S.J. Higgins, A.J. Turner, and E.J. Wood. Harlow, Longman, 1994, $14.99, softcover (xiii
+ 201 pages), ISBN o-582-10129-8. Essentials of Biochemistry, second edition. By Dorothy E. Schumm. Bos-
ton, Little, Brown, 1995,$29.95softcover
01996,
Elsevier
Science
Inc.,
1043-2760/96/$15.00
(xiii + 382 pages), ISBN O-316-77531-2. The Pituitary. Edited by Shlomo Melmed. Cambridge, MA, Blackwell,
1995, $150.00 (ix + 729 pages), ISBN O-86542-126-9. Small Group Tea&kg: A TroubleShooting Guide. By Richard G. Tiberius.
Toronto, Ontario Institute for Studies in Education, 1990, Cans26.50, softcover (viii + 216pages), ISBN o-7744-0344-6. SSDI
1043-2760(95)00202-2
39
a-ketoglutamte is a fascinating molecule that is a precursor of glutamine and arginine, but also of other amino acids and keto acids that are important in the control of protein metabolism. Ornithine a-ketoglutamte also has a potent secretagogic effect on hormones such as insulin and growth hormone. The last chapters of the section on ammo acid supply in disease deal with amino acid formulas devoted to specific situations. There is a chapter on amino acid support in catabolic illness such as trauma, surgery, inflammation, or infection. Campos and Meguid discuss the
amino acid requirements cial attention
in cancer. Spe-
is paid to the amino acid
solutions used for acute renal failure. Given the range and breadth text, it is most appropriate scientists,
and clinicians
the different
of this
for fellows, interested
in
aspects of amino acid me-
tabolism. Karl M. Nelson Director, office of Research Baptist Health System Birmingham,
AL 35213,
USA
SSDI 1043-2760(95)00200-6
Chewing and the Fat Food Intake and Energy Expenditure Edited by Margriet S. WesterterpPlanteng, Elisabeth W.H.M. Fredrix, and Anton B. Steffens, with Harry R. Kissileff as Editorial Advisor. Ann Arbor, CRC Press, 1994, $49.55 (408 pages), ISBN O-8493-9228-4. This book addresses the relationship between physiological and neurological responses to food, with the intent of providing a fresh understanding of obesity and misregulation of food intake. Unfortunately, the book is an example of good intentions gone astray. The fault can be placed on inadequacy in understanding and presentation, with the end result being a substandard book. The preface, consistent with the rest of the book, informs the reader that this is a textbook for students and that it has incorporated student feedback. The intended audience is students from a variety of academic disciplines that have a need to integrate concepts from among such areas as physiology, biology, psychology, and nutrition. The preface further informs the reader that the material is suitable for advanced investigators in these disciplines. The result serves neither students nor investigators because the book is poorly presented and edited, contradictory in delivery, superficial in topical coverage, and poorly researched. The material is presented in 23 chap ters, distributed among the subdivisions of (I) Psychobiology of Human Food In-
38
take, in five chapters, (II) Physiology and Endocrinology of Food Intake Regulation, in nine chapters, (III) Energy Expenditure, in seven chapters, and (IV) Food Intake, Energy Expenditure and Evolution, in two chapters. The book was developed to provide a cross-discipline linkage for integrated understanding among topics in biological, behavioral, and nutritional sciences at the Open University of the Netherlands. The underlying focus appears to be a rationale for the misregulation of food intake that leads to obesity. The hypothesis is that the misregulation can be found among the interactions of the neuroendocrine system with food intake, and that understanding neurological and hormonal alterations related to abnormal food intake can lead to a more rational approach to treatment of obesity. Obesity is a perplexing problem that has resisted definitive analysis and probably has many different etiologies. Treatment of obesity has not been very successful. Because obesity remains a major medical problem that has a serious impact on health and quality of life through direct association with hypertension, diabetes, cancer, stroke, and heart attacks, it is a subject worthy of further consideration. In simple terms, obesity develops because of an imbalance between energy intake and expenditure, and understanding the regulation of this balance would go along way toward dealing with obesity and its concomitant health problems. The preface to the book indicates that it contains
01996,
Elsevier Science Inc., 1043-2760/96/$15.00
new interpretations and a fresh look at factors that govern the lack of balance in developing obesity. Unfortunately, the goals set forth in the preface are not accomplished in the text. The presentation fails to convince the reader that the goals are attainable, and support for the hypothesis is not evident. The opening five chapters probably did not receive much student input because they are nearly verbatim from essays published in the Annals of the New York Academy of Science. The material is presented without the depth or detail necessary for student understanding and use. An example is the statement that “a simple formula yields the traditional measure of a justnoticeable difference (JND) . . . ,” but the formula, parameters, and limits of usefulness are not provided. The formula for a just-tolerable difference is also not provided. The language is discipline specific and aimed at experts in the field, consistent with its original publication. The language was not adapted for use in a textbook with an intended student audience and, consequently, is inadequate for students or investigators from other disciplines. The true shortcomings of these chapters are a failure to connect them with the apparent goals of the book. Part I deals with the psychology of short-term food intake and with estimating the factors that regulate the starting and stopping of meal eating. Yet, neither single-meal nor single-day eating relates to obesity development, as individuals of normal body fat also overeat, but adjust by undereating. Obesity develops from an ex-
TEM Vol. 7, No. 1, 1996
tended period of energy imbalance. Moreover, food intake and energy balance are not minute-to-minute regulatory processes, but are averages over extended durations. Although the discussion of what controls food intake at a single meal, as well as the initiation and termination of eating, is an important topic, it is interesting that the primary example of a regulatory substance is caffeine, which is not even a nutrient!-the same example that was used in the original essays. The second section is weak on style, presentation, and content. The length could have been greatly reduced if the ideas had been expressed in a straightforward manner. A prominent phrase “in other words” was too frequently used to re-explain a thought and, unfortunately, the second explanation did not always clarify the topic. Presentation alone was not the problem; inconsistencies abound, such as in Chapter 7, where the title promised “Feeding, Digestion, Absorption and Thermic Effect of Food” and yet the “them-tic effect of food” was neither mentioned nor discussed. A second example is energy expenditure, which is divided into three major components in Chapter 12 and into four components in Chapter 16. Inaccuracies are also present. On page 114, it is stated that “All absorbed nutrients reach the liver via the portal circuit . ..‘I and that included lipid. In Chapter 16, the reader is told that the “basal metabolic rate is
best predicted
from the fat-free mass as
this represents
the active cell mass....”
Although picky,
they
these
criticisms
are cited
Fat-free mass is a concept that has been
main problems
replaced with lean body mass. Active cell
thors
mass is a concept addressed
with energy expenditure
cell mass,
by the body
be the
with the book. The au-
have tried to link energy
intake
and have used
6
the physiological monitoring of dietary energy as a control point. These theo-
with this book as a guide for
ries, however, most clearly indicate that the authors have not done their home-
which
is not included.
The
number
of misstatements
through
14 is too great to enumerate.
Problems
may
to illustrate
in Chapters
students abound in the remaining
mate-
rial, and these problems will confuse the student and alienate established investigators. Selected examples follow. Hydrostatic weighing
is stated to be the gold
standard for determining
body composi-
tion, but then is stated to lack accuracy for individuals
with a low body-mass
dex. The latter is justified
in-
because values
obtained for fat mass are concluded to be unrealistically high. No justification for this conclusion
is provided. Further,
hydrostatic weighing is stated to overestimate changes in fat mass during weight loss and then is used to discuss in some detail fat mass loss in changing nutritional conditions. Another example is fiber, where the usual intake is shown as 4 to 7 g/day in one place and 10 to 30 g/day elsewhere. Such information should be edited prior to publication or the differences explained. Similarly, we are informed in one place that the usual energy intake cannot be determined, although elsewhere take is discussed.
the usual energy
in-
work. Dietary energy and energy expenditure are independent processes and are not related via feedback mechanisms. Alteration of food caloric density tends to change the energy intake because volume, rather than nutrient content, controls intake. If dietary energy were monitored, why would people get obese? Why can we overeat and undereat while maintaining body weight? Dr. Flatt has discussed this concept in some detail, and this book does not refer to his work. The authors have put forth a hypothesis based on inadequate knowledge of the relevant literature and have supported the hypothesis with information that is poorly presented. I would not recommend this book. Ronald H. Birkbabn
Departments of Surgery and BiochemistrylMolecular Biology Medical College of Ohio Toledo, OH 43699-0008, USA SSDI
1043.2760(95)00203-O
BOOKS RECEIVED We thank the publishers for sending us the books listed here. Those we deem of interest to our readers will be reviewed. Readers are invited to write book reviews by informing the Book Review Editor of the title and publisher of books you wish to review. Please address all correspondence for book reviews to Lee A. Meserve, PhD, Book Reviews, Trends in Endocrinology and Metabolism, c/o Department of Biological Sciences, Bowling Green State University, Bowling Green, OH 43403-02 12.
TEM Vol.7,No.1,1996
Biochemistry. Fourth Edition. By Lubert Stryer. New York, W.H. Freeman, 1995, $69.95 (xxxiv + 1064 pages), ISBN O-7 167-2009-4. Biochemistry for the Medical Sciences: An Integrated Case Approach. By S.J. Higgins, A.J. Turner, and E.J. Wood. Harlow, Longman, 1994, $14.99, softcover (xiii
+ 201 pages), ISBN o-582-10129-8. Essentials of Biochemistry, second edition. By Dorothy E. Schumm. Bos-
ton, Little, Brown, 1995,$29.95softcover
01996,
Elsevier
Science
Inc.,
1043-2760/96/$15.00
(xiii + 382 pages), ISBN O-316-77531-2. The Pituitary. Edited by Shlomo Melmed. Cambridge, MA, Blackwell,
1995, $150.00 (ix + 729 pages), ISBN O-86542-126-9. Small Group Tea&kg: A TroubleShooting Guide. By Richard G. Tiberius.
Toronto, Ontario Institute for Studies in Education, 1990, Cans26.50, softcover (viii + 216pages), ISBN o-7744-0344-6. SSDI
1043-2760(95)00202-2
39