Joe Mercola, the font of much Internet poppycock, thinks that the safety of ice cream is somehow related to the ease with which it melts. He and other bloggers not well versed in science suggest that ice cream that does not melt easily should be avoided. There are ice creams that don't melt as readily as others but that doesn't mean that eating them poses a risk. There are a number of factors that determine how readily an ice cream melts. Basically, the melting rate is determined by the additives used. Ice cream is a mixture of fat globules, water, sugar and air. For a smooth texture the separation of fat and water must be avoided as well as the formation of large ice crystals. Emulsifiers such as mono and diglycerides prevent the fat from separating and guar gum and calcium sulphate add thickness. The thick texture also results in an ice cream that is more difficult to melt.There is no problem with these additives. The glycerides are basically a type of fat that occur naturally in many foods, guar gum is extracted from a bean and calcium sulphate is used in much higher doses in calcium supplements. People who suggest that ice cream is somehow toxic because it stays solid longer need to solidify their knowledge of chemistry.