India, June 11 -- On April 17, 1919, a sharp-tongued anonymous letter from a Poona doctor appeared in a Bombay newspaper, offering urgent seasonal advice.

"Were we to pursue the plan of eating the heat-producing breakfasts in summer, which we found beneficial to our well-being in winter, a highly feverish state of blood would be produced, and inflammatory diseases created. Hence, less fats, sweets, and starch, as in fine flour, are needed. Muscle-building foods, such as the darker portions of grains, milk, lean meats, fowl, and fish, should be preferred. Use the early salads and cooling vegetables which succeed each other in this season. The delightful berry and melon should be freely eaten," the letter read.

But the doctor's real targe...