It is just because of the persistent way in which this mischief acts that it forms one of the deadliest foes against which the human body has to contend. Its malign influence is so continuous and so all-pervading that it becomes one of the most potent factors in predisposing to breakdowns. No sacrifice, either of time or money, is too great that will help to prevent it or keep it in check. CHAPTER IX. HOW MUCH FOOD TO TAKE. Speaking generally, the amount should be sufficient to keep the body well and active, but not to load it up with more than it can get rid of. [Sidenote: Personal requirements.] As to the actual amount, there is no guide save that of personal requirements. Some people need more than others, and without any reference to the size of the individual. A little man may easily require twice as much as a big one. It depends on the rate at which his system burns it up. It is of no use, therefore, to judge of our own needs by those of other people. A noted big game hunter is said to be able to take three full-course dinners in immediate succession, without the slightest inconvenience or any apparent detriment to his health. Such persons can be regarded only as freaks, and any attempt on the part of others to imitate their example would lead to disaster. For we could no more follow his lead in this respect than we could do what he is also capable of, namely to go for three days and nights without food or drink, and feel no worse for so doing. [Sidenote: Appetite.] Appetite will usually be found a sound guide, provided that it is not satisfied to the point of repletion. It is always well to eat steadily and moderately, following the time-worn plan of rising from the table feeling as if you could eat more. Sometimes a man will sit down as hungry as a hunter, attacking his viands with avidity. Two hours later he wishes that he had not. He has taken more than his digestion can cope with, and the result is that for a day or two afterwards he can scarcely eat anything. If there is an excess of appetite, so to speak, left over, it will keep until the next meal. Regularity in amount, as well as in times of feeding, is essential to health. As a rule people eat too much, and need to be reminded of the fact, tactfully of course. It is astonishing to watch the improvement in health and energy which often follows a reduction in the amount of food taken. Many listless, tired patients become bright and vigorous after they have been persuaded to adopt this course. It is not uncommon to see thin people who have been overfed by their anxious relatives, and have become sallow and dyspeptic in consequence. In such cases it is difficult to convince the individual himself, and still harder to convince his friends, that he will not become thinner if he takes less food. Yet practical experience has shown that he not only fails to lose weight, but in many cases even puts it on.