Let us assume that you get the biggest plain, enriched bagel analyzed by the U.S. Department of Agriculture, 4 inches in diameter, weighing 110 grams, about 3.8 ounces.
The ingredients flour, water, salt, yeast, and malt, but no sugar, if it is a classic bagel —are boiled and then baked. They add up to 302.5 calories, the USDA says.
On a standard nutrition facts label, the bagel would boast 1.76 grams of fat, no cholesterol, 587.4 milligrams of sodium, 111.1 milligrams of potassium, 58.74 grams of carbohydrate, and 11.55 grams of protein.
Vitamins and minerals include a significant amount of folate, 96.8 micrograms, from the enriched flour, but most others are present in trace amounts. A bagel preserved with calcium propionate has more calcium than one without it: 81.4 milligrams, compared with 19.8 milligrams.
Oddly, the USDA does not differentiate among plain, onion, poppy seed, and sesame bagels. Poppy seed, which the department considers a spice, not a food, would probably not add enough calories to make a weight watcher feel guilty.
There are only about 15 calories in a teaspoonful, fewer calories than would be in a spoon of sugar. Sesame seeds have perhaps 26 calories in a teaspoonful, figured at a sixth of an ounce, by volume.