above normal, has fixed in every one's mind the interchangeableness
of these two foods. Potatoes are one-fifth starch--almost the same
quantity as in cooked breakfast cereals. Because of this starch, they
give as satisfactory a fuel as wheat or corn or any other cereal. One
medium-sized potato supplies the same number of calories as a large
slice of bread, and contains more mineral salts than white bread.
Europe has learned to eat potatoes instead of wheat. When bread has
been short potatoes have been the mainstay in every country. They are
to-day the largest single element, in terms of energy, in the German
war ration.

Sweet potatoes are also first-class wheat-savers. So to a lesser
extent are most vegetables and fruits. Very few except white and
sweet potatoes contain much starch, but many of them have considerable
sugar, which serves as fuel just as starch does--carrots, beets,
onions, parsnips, and practically all fruits such as bananas, oranges,
and grapes.

_To Save Sugar_. We want sugar, of course, both for fuel and flavor.
The vegetables and some fruits have their sugar so covered up by
other tastes that it does not help to make the food sweet. It does, of
course, serve for fuel. Bananas especially are fuel foods, containing
much starch when green, which changes to sugar as the fruit ripens.
The sweetest fruits are the dried ones--dates, figs, raisins, prunes.
They have so much sugar that they can well be used in place of candy.

_To Save Fat_, Although few common fruits and vegetables contain
fat, jam is a real fat-saver. It is of high fuel value, and has the
advantage of being a "spreading material" so that it can replace
butter with bread and cereals. Jam is of great importance in Europe