Technically, white chocolate isn’t even chocolate, although it is made from the cocoa bean. During processing, the fat in cocoa (known as cocoa butter) gets separated from the cocoa solids. When making milk chocolate or dark chocolate, the cocoa solids and cocoa butter get recombined in various proportions. When making white chocolate, the cocoa butter alone is mixed with milk and sugar.
The Fat Profile of Cocoa Butter
Although it’s technically a vegetable fat (and we normally want to avoid vegetable fats) cocoa butter is almost entirely saturated and monounsaturated fats. We prefer these forms of fat because they are much more stable than polyunsaturated forms, which tend to oxidize when exposed to heat and light.
Although it’s a healthy fat, mixing it with milk and sugar takes away much, if not all of the health benefits of consuming the fat. White chocolate is also missing all of the micronutrients that make dark chocolate a health food, including minerals and anti-oxidants. The result is a sweet treat with little to no nutritional value.
Mark Sisson has an excellent post on why all chocolate is not created equal.