Dark red beauty. Tart cherries originated from northern India and Iran, and it is likely that it was the Persians and Romans, who regularly enjoyed their tart, refreshing flavour that introduced this fruit to the rest of the world. They are characterised by their dark red colour, provided by the pigment anthocyanin. Tart cherries are low in fat and calories (100 g have just 50 calories), but are rich in vitamin C. A study published in the journal Experimental Biology in 2014 showed that a glass of tart cherry juice in the morning and evening improved sleep quality in comparison to a placebo. The authors claimed that the 'sleepy' effect of tart cherry juice is do to the hormone melatonin, naturally found in tart cherries, and which plays a key role in the sleep cycle. *Liu AG, Tipton RC, Pan W, Finley JW, Prudente A, Karki N, Losso JN, Greenway FL. Tart cherry juice increases sleep time in older adults with insomnia. Experimental Biology 2014. San Diego, CA. April 28, 2014.