Mars introduced M&M's Peanut Chocolate Candies to the market in 1954, and the candies have been a Halloween staple ever since. Consume these treats in moderation. They have a significant amount of saturated fat.

A regular-size bag of M&M's Peanut Chocolate Candies, weighing approximately 54 g, contains 278 calories.

A bag of M&M's Peanut Chocolate Candies has 32.66 g of carbohydrates, 14.11 g of fat and 5.17 g of protein. The calorie composition is approximately 47 percent carbohydrate, 46 percent fat and 7 percent protein. Almost 5.5 g, or 40 percent, of the total fat content is saturated fat, and the saturated fat content equals 37 percent of the total daily saturated fat intake recommended for healthy adults.

The bag of candy has 11.3 percent of the recommended dietary allowance of niacin, 10.3 percent of the RDA of vitamin E, 9.3 percent of the RDA of magnesium, 8.6 percent of the RDA of phosphorus, 7.5 percent of the RDA of folate, 7 percent of the RDA of vitamin B-12, 6.8 percent of the RDA of pantothenic acid, 6.3 percent of the RDA of zinc and trace amounts of other vitamins and minerals.