How and Why We Age

by HAYFLICK, LEONARD PHD

• ISBN13: 9780345401557
• ISBN10: 0345401557
• Edition: 1st
• Format: Trade Paper
• Copyright: 1996-01-01
• Publisher: Ballantine Books

Summary

"How long can humans live? Is immortality possible? Just what is the aging process? The aging and inevitable death of the human body have inspired more myths and outrageous quackery than anything else subject to scientific inquiry. . . . Now comes a most fascinating book, insightful and scholarly, to provide what answers have emerged so far." --San Francisco Chronicle Here, at last, preeminent cell biologist Leonard Hayflick presents the truth about human aging. Based on more than thirty years of pioneering research in the field, How and Why We Age explores not only how our major biological systems change as we grow older, but also examines the intangible alterations in our modes of thinking and feeling, our moods and sexual desires, our personality traits and our memories. With the immediacy of the latest scientific discoveries, Dr. Hayflick explains how aging affects every part of the body, and dispels many of the most persistent aging myths, to show that: * Hearts do not naturally get weaker with age. * Regular exercise and a low-fat diet won't slow aging. * Curing cancer would only add two years to the average sixty-five-year-old American life. Curing heart disease, however would add fourteen years. * Only five percent of people over the age of sixty-five are in nursing homes * No human has lived--or probably can live--past 120 years. Gracefully written, clearly organized, and packed with essential facts and statistics, How and Why We Age is a landmark study of the aging process for readers of all ages. "Written in clear, nontechnical language, it is an excellent introduction to the scientific and demographic literature on this multifaceted subject." --Nature

Table of Contents

FOREWORD	xiii	(4)
Robert N. Butler, M.D.
PREFACE	xvii	(4)
PROLOGUE TO THE PAPERBACK EDITION	xxi	(10)
ACKNOWLEDGMENTS	xxxi
Introduction	1	(10)
PART ONE: What Is Aging?	11	(42)
1. Defining Aging	11	(8)
Chronological versus Biological Age	12	(3)
Longevity, Aging, and Death	15	(1)
How Old Are You--Really?	16	(3)
2. Some Animals Age, Some Do Not	19	(15)
Animals That Do Not Age	21	(2)
Aging by Wear and Tear	23	(1)
Animals That Regenerate	24	(1)
"Big Bang" Reproduction and Aging	24	(3)
How Long Do Animals Live?	27	(7)
3. Redwood Trees Are Not Old	34	(9)
Aging and Cell Lineages	35	(1)
Grafts and Aging	36	(1)
Roots, Shoots, and Aging	36	(1)
Programmed Aging	37	(2)
The Longevity of Seeds	39	(4)
4. Aging Is Not a Disease	43	(10)
Normal Age Changes	44	(1)
Causes of Death	45	(2)
Age-related Illnesses	47	(1)
Population versus Individual Aging	48	(5)
PART TWO: Aging by the Numbers	53	(58)
5. The Demographic Facts of Life	53	(10)
The Graying of America	54	(3)
The Statistics Today	57	(2)
The Statistics Tomorrow	59	(1)
Some Geographical Facts	59	(4)
6. Actuarial Aging	63	(26)
The Likelihood of Death	64	(2)
Are We Living Longer?	66	(1)
How Many Years Are Left?	67	(1)
The Tables of Life	68	(9)
Life Tables for Animals	77	(1)
The Curves of Life	77	(6)
Rectangularizing the Survival Curve	83	(1)
Yes, We Are Living Longer	84	(5)
7. A Long and Healthy Life	89	(22)
What Is Your Active Life Expectation?	90	(2)
Extending Health and Compressing Illness	92	(1)
Is Life Span Fixed or Changing?	93	(1)
Do Some Occupations Favor Longevity?	94	(2)
What Will Happen When All Diseases Are Cured?	96	(5)
Why Do Women Live Longer than Men?	101	(3)
Is There a Weaker Sex?	104	(3)
Accelerated Aging in Humans	107	(1)
Why Are We Old at Age Sixty-five?	108	(3)
PART THREE: How Do We Age?	111	(78)
8. Aging under Glass	111	(26)
Aging in a Bottle	112	(4)
An Old Dogma Dies	116	(8)
Transplanting Normal Cells	124	(2)
Aging Adult Cells	126	(1)
Accelerated Aging in a Bottle	126	(1)
Carrel's Mistake	127	(3)
Life in the Cold	130	(1)
Cellular Memory	130	(1)
A Practical Use	131	(1)
Cell Aging and Cell Longevity	132	(4)
The Latent Period	136	(1)
9. The Baltimore Longitudinal Study of Aging	137	(13)
The BLSA	139	(3)
Separating Facts from Myths	142	(1)
Changes in Appearance	143	(1)
Dental Changes	143	(1)
Weight and Metabolic Changes	143	(1)
Changes in the Cardiovascular System	144	(1)
Changes in Reaction Time	144	(1)
Cognitive Changes	144	(1)
Personality Changes	145	(1)
Changes in Sexual Activity	145	(1)
Changes in the Senses	146	(1)
Physiological Changes	146	(1)
Changes in Strength	147	(1)
Gender Differences in Aging	147	(1)
General Conclusions from the BLSA	148	(2)
10. How We Change with Age	150	(16)
The Cardiovascular System	151	(2)
The Immune System	153	(2)
The Endocrine System	155	(2)
The Female Reproductive System	157	(2)
The Male Reproductive System	159	(1)
The Skeletal System	160	(1)
The Nervous System	161	(1)
The Brain	161	(5)
11. Aging from Head to Foot	166	(23)
Height	166	(1)
Weight	167	(1)
Chest Size	168	(1)
Arm Span	168	(1)
Face	168	(1)
Skull	168	(1)
Skeleton	169	(1)
Body Composition	169	(1)
Body Water	169	(1)
Skin	170	(4)
WRINKLES
SWEAT GLANDS
TEMPERATURE CONTROL
HEALING CAPACITY
Fingernails	174	(1)
Hair	175	(1)
Hearing	176	(1)
Taste	177	(1)
Smell	178	(1)
Sight	179	(1)
Sleep	179	(2)
Nutrition	181	(1)
Metabolism	182	(2)
Capacity for Exercise	184	(1)
Chronic Diseases	185	(1)
Aging Has Its Compensations	185	(4)
PART FOUR: Why Do We Age?	189	(76)
12. Centenarians and Supercentenarians	189	(19)
Superlongevity throughout the Ages	190	(6)
LUIGI CORNARO AND THE SPARTAN LIFE
DESCARTES AND BACON
EARLY BLOOD TRANSFUSIONS
SUPERLONGEVOUS INDIVIDUALS
MODERN SKEPTICISM
Are There Superlongevous People?	196	(6)
What about Centenarians?	202	(1)
The Increased Likelihood of Reaching Age One Hundred	203	(3)
Some Statistical Characteristics of Centenarians	206	(2)
13. Determining Life Span	208	(14)
How Life Span Relates to Brain Weight and Body Weight	208	(4)
Body Temperature and Metabolic Rate	212	(1)
Lengthening Life Spans	213	(2)
Did Aging Evolve?	215	(1)
The Importance of Redundancy	216	(6)
14. Theories of Aging Based on Purposeful Events	222	(14)
Early Ideas about Aging	223	(3)
THE "VITAL SUBSTANCE" THEORY
THE GENETIC MUTATION THEORY
THE REPRODUCTIVE EXHAUSTION THEORY
Why Modern Theories of Aging Are Still Speculative	226	(2)
Rules of the Game	228	(1)
Is Aging Accidental or Programmed?	229	(1)
Aging by Design	229	(2)
The Neuroendocrine Theory	231	(2)
Down the Brain-cell Drain	233	(3)
15. Theories of Aging Based on Random Events	236	(29)
The Wear and Tear Theory	236	(3)
The Rate of Living Theory	239	(2)
The Waste Product Accumulation Theory	241	(1)
The Cross-linking Theory	242	(2)
The Free Radical Theory	244	(4)
The Immune System Theory	248	(2)
Theories of Errors and Repairs	250	(7)
The Order to Disorder Theory	257	(1)
So Why Do We Age?	258	(1)
A Personal View	259	(6)
PART FIVE: Slowing Aging and Increasing Life Span	265	(48)
16. Early Attempts to Control Aging	265	(12)
Should We Try to Cheat Death?	265	(2)
Should We Try to Control Aging?	267	(2)
Rejuvenating Substances	269	(1)
Alchemy	269	(2)
Cavorting	271	(1)
Scrotum Hokum and Other Nonsense	272	(2)
Cell Therapy	274	(1)
Yogurt	274	(1)
Sterilization	275	(1)
Procaine	276	(1)
17. How Exercise, Nutrition, and Weight Affect Longevity	277	(19)
The Effect of Exercise on Aging and Life Span	278	(2)
The Longevity of College Athletes	280	(2)
The Longevity of Baseball Players	282	(1)
The Longevity of Old Athletes	282	(1)
Is There an Antiaging Diet?	283	(4)
How Does Caloric Restriction Work?	287	(2)
Can Humans Increase Their Longevity by Caloric Restriction?	289	(3)
Ideal Weight and Longevity	292	(4)
18. How Temperature, Light, Transfusions, and Suspended Animation Affect Longevity	296	(7)
Temperature and Aging	296	(2)
Suspended Animation	298	(2)
Cryonics	300	(1)
Aging in the Dark	301	(1)
Can Transfusions Affect Longevity?	302	(1)
19. The Clocks That Time Us	303	(10)
Our Perception of the Passage of Time	304	(1)
Circadian Rhythm	305	(2)
Where Is the Clock?	307	(1)
Aging Clocks	308	(1)
A Sure Way to Slow Aging	308	(2)
An Easy Way to Increase Your Longevity	310	(3)
PART SIX: The Future of Human Aging and Longevity	313	(30)
20. Life Extension and Antiaging Therapies	313	(5)
Antiaging Therapies and Profits	314	(1)
How Do We Test What Cannot Be Measured?	315	(1)
What Would Happen if We Learned How to Manipulate Longevity?	315	(1)
At What Age Are We Most Productive?	316	(2)
21. Aging and Longevity in the Twenty-first Century	318	(25)
The Effect of Genetics on Future Longevity	319	(2)
The Effect of Nurture on Future Longevity	321	(1)
Twenty-first century Demographics	322	(3)
Our Future Selves	325	(5)
Living the Rectangular Life	330	(1)
Can We Extend Our Life Span?	331	(1)
Research on Longevity and Aging Today	332	(2)
What Should Our Goals Be?	334	(2)
No More Aging: Blessing or Nightmare?	336	(2)
Immortality	338	(1)
The Population Bomb	339	(2)
How to Increase Life Expectation	341	(2)
FURTHER READING	343	(18)
INDEX	361