Cacao tree belongs to the family Malvaceae, native to the deep tropical regions of Mesoamerica. Its seeds and beans are used to make chocolate liquor, cocoa solids, cocoa butter and chocolate.

Yes, you heard me right. Cocoa are Cacao are different from one another. Though they start their journey from the same station i.e. the cacao plant, yet they end up to different final destinations with major differences in their nutritional values.
Theobroma cacao or the cacao tree, also known as the ‘food of the Gods’ produced many cocoa pods. These pods include beans (which are later converted into cocoa or cacao) and a white fleshy pulp called Baba (which is used in making white chocolate).

Cocoa starts its journey from cacao. Cacao seeds are raw beans from the cacao plant. They undergo fermentation process that develops their distinct chocolate flavour and aroma. The dried, roasted and crushed beans then form nibs that are used to make cocoa.

It is the roasting process that converts cacao to cocoa. Cacao is made from fermented, dried, unroasted cacao beans. Being unprocessed they contain a higher amount of nutritional values that the cocoa looses to the heat. The roasted beans are further treated with alkaline to reduce its bitterness. This makes them loose 60% of their flavanol.

Cacao contains flavanols, which have various antioxidant, heart-protective and anti-cancer properties. They are a good source of several minerals, including selenium, magnesium, chromium and manganese. They are rich in tryptophan, an amino acid our body uses to make serotonin (a brain chemical that helps the mind relax).
The polyphenols in cacao is linked to numerous health benefits, including reduced inflammation, better blood flow, lower blood pressure and improved cholesterol and blood sugar levels

Bottom line : Higher bitterness indicates higher content of cacao, and hence provides more nutritional benefits.