A digestive biscuit, sometimes referred to as a sweetmeal biscuit, is a semi-sweet biscuit or cookie, popular in the United Kingdom, in other Commonwealth countries, and the Republic of Ireland. The name "digestive" derived from the belief that they had antacid properties due to the use of bicarbonate of soda when they were first developed.
The digestive biscuit was invented by McVitie's in Edinburgh in 1799 by Alexander Grant. They were advertised as aiding digestion, and subsequent scientific research has concluded this is true. While rumours exist that consequently it is illegal for them to be sold under that name in the USA, in fact they are widely available in imported food sections of grocery stores and by mail order. The Original Digestive biscuit is still the ninth-biggest biscuit brand in the UK.
A biscuit averages around 70 calories, although this sometimes varies according to the factors involved in its production.
In the UK alone, the annual sales of chocolate digestives total about £35 million. This means that each year, 7 billion packets of these are sold - and each second, 51 biscuits are consumed. Digestives are also popular in cookery for making into bases for cheesecakes and similar desserts.
Chocolate digestive biscuits also are available, coated on the top in plain, milk, or white chocolate. Originally produced by McVitie's in 1925, other recent varieties include the basic biscuit with chocolate shavings throughout, or a layer of caramel, mint chocolate, orange-flavored chocolate or plain chocolate. The US travel writer Bill Bryson described the chocolate digestive as a British masterpiece.