Which food has less impact on blood sugar?

WHOLE WHEAT BUN (STONE GROUND WHOLE WHEAT FLOUR, WATER, HONEY, WHEAT BRAN, WHEAT GLUTEN, DOUGH CONDITIONER [GUM ARABIC AND/OR GUAR GUM, WHEAT FLOUR, SOYBEAN OIL, ENZYMES], CANOLA OIL, SALT, YEAST, VINEGAR, ASCORBIC ACID), PLAIN BUN (ENRICHED UNBLEACHED FLOUR [WHEAT FLOUR, NIACIN, REDUCED IRON, THIAMIN MONONITRATE, RIBOFLAVIN, FOLIC ACID], WATER, SUGAR, CONTAINS 2% OR LESS OF THE FOLLOWING: DOUGH CONDITIONERS [{WHEAT FLOUR, MALTED BARLEY FLOUR, ASCORBIC ACID, ENZYMES}, {GUM ARABIC AND/OR GUAR GUM, WHEAT FLOUR, SOYBEAN OIL}], SEA SALT, YEAST, SYRUP [CORN SYRUP, MALT SYRUP, CARAMEL COLOR], WHITE DISTILLED VINEGAR, RAISIN JUICE CONCENTRATE, OLIVE OIL), HAM CURED WITH WATER, HONEY SUGAR, SALT, SODIUM PHOSPHATE, SODIUM ERYTHORBATE, SODIUM NITRITE. TURKEY BREAST (TURKEY BREAST MEAT, TURKEY BROTH, HONEY, SUGAR, SALT, SODIUM PHOSPHATE, SODIUM ERYTHORBATE, SODIUM NITRITE), MILD CHEDDAR CHEESE (PASTEURIZED MILK, CHEESE CULTURES, SALT, MICROBIAL ENZYMES, ANNATTO [FOR COLOR], NATAMYCIN), SWISS CHEESE (PASTEURIZED MILK, CHEESE CULTURES, SALT, MICROBIAL ENZYMES), LETTUCE