Only one lease of life is granted us; and the inquiry with every one should be, “How can I invest my powers so that they may yield the greatest profit? How can I do most for the glory of God and the benefit of my fellow men?” For life is valuable only as it is used for the attainment of these ends.
Our first duty toward God and our fellow beings is that of self-development. Every faculty with which the Creator has endowed us should be cultivated to the highest degree of perfection, that we may be able to do the greatest amount of good of which we are capable. Hence that time is spent to good account which is used in the establishment and preservation of physical and mental health. We cannot afford to dwarf or cripple any function of body or mind. As surely as we do this, we must suffer the consequences.
Every man has the opportunity, to a great extent, of making himself whatever he chooses to be. The blessings of this life, and also of the immortal state, are within his reach. He may build up a character of solid worth, gaining new strength at every step. He may advance daily in knowledge and wisdom, conscious of new delights as he progresses, adding virtue to virtue, grace to grace. His faculties will improve by use; the more wisdom he gains, the greater will be his capacity for acquiring. His intelligence, knowledge, and virtue will thus develop into greater strength and more perfect symmetry.
On the other hand, he may allow his powers to rust out for want of use, or to be perverted through evil habits, lack of self-control, or moral and religious stamina. His course then tends downward; he is disobedient to the law of God and to the laws of health. Appetite conquers him; inclination carries him away. It is easier for him to allow the powers of evil, which are always active, to drag him backward, than to struggle against them, and go forward. Dissipation, disease, and death follow. This is the history of many lives that might have been useful in the cause of God and humanity.
-Counsels on Diet and Foods p. 15