| PAGE | |
| On the Appearance of Symptoms of Old Age in Young Persons | 1 |
| On the Agencies which Govern our External Appearance and the Nutrition of the Tissues | 11 |
| On the Agencies which Govern Immunity Against Infections and Intoxications—The Origin of Fever | 21 |
| On the Agencies that Govern the Condition of the Nervous System and Mentality | 35 |
| On the Influence of the Sexual Glands upon Vitality and Long Life | 45 |
| On Heredity and Longevity | 55 |
| On Means which can Help us to Determine the Probable Duration of Life | 64 |
| On the Causation of Old Age | 90 |
| The Rational Prevention of Premature Old Age and the Treatment of Old Age | 114 |
| The Destruction and Elimination of Toxic Products from the Body and Hygienic Measures for the Improvement of these Functions | 134 |
| On the Destruction of Poisonous Products Through the Thyroid and Parathyroid Glands | 138 |
| Hygiene of the Thyroid Gland | 145 |
| The Destruction of Toxic Products by the Liver and the Improvement of its Protective Functions | 149 |
| The Hygiene of the Liver | 155 |
| On the Destruction of Toxic Products by the Adrenals | 159 |
| Hygiene of the Adrenals and of the Circulatory System—A Few Remarks on the Cause, Prevention, and Treatment of Arteriosclerosis | 164 |
| The Elimination of Toxic Products Through the Intestines and the Improvement of This Function | 170 |
| On the Prevention and Treatment of Habitual Constipation | 175 |
| Hygiene of the Intestines | 182 |
| Hygiene of the Intestines—A Few Remarks on the Cause and Prevention of Appendicitis | 192 |
| On the Elimination of Toxic Products Through the Kidneys | 197 |
| Hygiene of the Kidneys, and the Prevention of Renal Disease | 203 |
| On the Elimination of Toxic Products Through the Skin | 209 |
| The Hygiene of the Skin—Air Baths | 215 |
| On Rational Clothing | 219 |
| Improved Hygiene of the Skin and Kidneys through Bathing—Foot-baths | 231 |
| Hygiene of the Skin and Kidneys by Means of Perspiration | 237 |
| On Exercise, Swedish Gymnastics—Massage—Sport, and Walking and Running Exercise | 244 |
| A Few Remarks on Cold Feet—Their Cause and Treatment | 252 |
| On the Benefits of Sunlight | 255 |
| On the Advantages of an Open Air Life and of Breathing Exercises | 262 |
| On the Dangers of Living in Confined and Ill-Ventilated Quarters | 271 |
| Hygiene of Artificial Heating—the Dangers of Heat by Steam and a Few Hints about their Prevention | 275 |
| Food Hygiene—General Remarks | 280 |
| On Proteid Food, Animal Food, Meat, Fish, Eggs, Milk, etc. | 294 |
| On Carbohydrates and Fats, and the Great Advantages of Vegetables and Fruit | 301 |
| On the Advantages and Disadvantages of a Vegetarian Diet | 309 |
| On the Dangers of a Too Abundant Meat Diet—A Few Hints on the Dietetics of Meat | 317 |
| On the Great Advantages of Much Milk in the Diet for the Prevention and Treatment of Old Age | 325 |
| On Blood as an Article of Food Containing Iron and Animal Extracts—Sausages and Blood Puddings | 333 |
| Some Remarks on the Hygiene of Eating—How to Obtain an Appetite—On Mastication | 339 |
| On the Uses of Small Doses, and the Deleterious Action of Large Quantities of Alcohol | 347 |
| Some Remarks on the Causes and Prevention of the Alcohol Habit | 356 |
| On Other Stimulants—Tea, Coffee, Cocoa, Tobacco: Their Merits and Disadvantages | 362 |
| On Sleep, and Its Importance in Ridding the Body of Toxic Products | 368 |
| On the Causation of Sleep, Sleepiness, and Insomnia | 372 |
| Hygiene of Sleep—Prevention of Insomnia | 377 |
| The Treatment of Sleepiness and Insomnia | 383 |
| Hygiene of the Sexual Glands—the Dangers of Sexual Overactivity and of Total Sexual Abstinence | 389 |
| On Married Life as an Important Means for Prolonging Life | 400 |
| Hygiene of the Mind—Emotions and Worry as Causes of Old Age | 404 |
| Hygiene of the Mind—Religious Belief as a Means of Prolonging Life | 414 |
| Disease Considered as a Self-defence of Nature | 419 |
| Hygiene of the Mind—Advice to Brain Workers | 423 |
| On the Prevention of Premature Old Age, and the Treatment of Old Age, through Certain Drugs: Arsenic, Iron, and Iodides | 426 |
| On the Prevention of Premature Old Age and on the Treatment of Old Age by Animal Extracts | 434 |
| A Few Hints on Youthful Appearance | 449 |
| The “Twelve Commandments” for the Preservation of Youth, and the Attainment of a Green Old Age | 455 |
| Glossary | 459 |
| Index | 467 |
| Footnotes | 494 |