This section is from the book "The Hygienic System: Fasting And Sun Bathing", by Herbert M. Shelton. Also available from Amazon: The Hygienic System Vol III Fasting and Sun Bathing.
The thin and weak individual, knowing little or nothing of fasting, may be excused for his fear of fasting, but the plethoric and overweight individual certainly cannot be excused. The bear eats heartily of nuts, honey, fruits, flesh, etc., while these are plentiful, and puts on a great store of fat with which to sustain his body during the winter season. The frog also stores up considerable fat for this occasion. There are hundreds of thousands of men and women who carry greater stores of fat than the bear or frog, who imagine that if they miss so much as a single meal they will begin to grow weak. They carry sufficient fat and other food reserves to last them for weeks and even months. They could fast for prolonged periods, not only without harm to themselves, but with positive benefit. Thin people also carry a reserve supply and may safely fast for considerable periods if they are properly supervised.