If you are having struggling with sleep problems, Central Otago cherries could be just the bedtime remedy, say researchers. They say Cherries grown in sun-rich Central Otago are a natural source of melatonin at levels 30 times higher than their northern hemisphere counterparts. Melatonin is a hormone that is naturally present in the human body and aids sleep. The findings come from research commissioned by Fruision Ltd, a joint venture between Hamilton-based Quantec Ltd, a company specialising in developing health remedies from natural products, and Alexandra-based fruit grower Summerfrui, Stuff.co.nz reported. Previous studies published in the United States have shown northern hemisphere cherries to have levels of melatonin at two to 15 nanograms per gram. The latest study, undertaken by an independent laboratory in Australia, has shown Central Otago cherries have 500 nanograms per gram. When the cherries had been dried, the melatonin levels increased to 3100 nanograms per gram. Fruision senior scientist Dr Judy Bragger said Kiwi plants are exposed to more ultraviolet radiation than those growing at a similar latitude in Europe of North America, and this caused them to produce more secondary metabolites -- organic compounds that are not directly involved in the normal plant growth. \"It is these secondary metabolites that the cherries produce that have such great human health promoting properties when eaten,” Dr Bragger stated. Moanui Laboratories in Hamilton were already backing the science and are the first New Zealand company to distribute a sleep aid derived from cherries in a capsule form.