Meat preservatives implicated in New Zealand's diabetes crisis

• Auckland University research points the finger at nitrates and nitrites as a potential cause of some child-onset diabetes.
• They are used to preserve meats such as salami and ham and nitrates occur naturally in vegetables.
• Around 15,000 people in New Zealand have type 1 diabetes and the incidence has doubled in the past 20 years.
• This trigger has not been found, despite researchers considering viruses and a huge range of potential dietary causes.
• Auckland University scientist Dr Shiva Reddy said his research on mice strongly supported the theory that nitrates caused some type 1 diabetes.
• He gave tiny doses of a drug called streptozotocin to mice who were genetically prone to developing type 1 diabetes and to another group who were not prone.
• The chemical is involved in a similar cellular pathway to nitrates and is known to destroy insulin- producing cells when given in large doses.
• Diabetes researcher Professor Bob Elliott, of the biotech company Living Cell Technologies, said Dr Reddy was doing pioneering work on the disease which backed the nitrates theory.
• Dr Reddy was the first to do laboratory experiments underpinning overseas survey work that had suggested a link between the disease and nitrates.
• Scientists in Melbourne had found a substance like streptozotocin on the skins of potatoes.
• A study by the Institute of Environmental Science & Research said more than 97 per cent of exposure to nitrates from 24 vegetables and processed foods it checked was from the vegetables, especially lettuce and potato.
• But the levels in New Zealand lettuce and potato were not high compared with European results.
• The population's average exposure to nitrates and nitrites were well within the acceptable daily intakes, the study said.