The campaign, created by integrated agency Domain, will include a mailing to 150,000 people with diabetes, encouraging them to join the charity.
The mailout, which carries the headline "Peace of mind", explains that for £20, or £9 for those with reduced income, sufferers can receive information, help and advice about their condition.
The activity will be backed by press ads breaking later this month in national daily and Sunday newspapers.
The direct drive will be assessed before forming the basis of a six-figure push in the autumn.
About 1.8m people in the UK have diabetes: however, the figure is expected to grow rapidly with the rise in obesity.
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