For 40 years, the Havering Diabetes Group has been supporting people in the borough who share the same condition.
To mark the special occasion, the group will be holding a special dinner on July 15.
Debbie Broom, chairwoman of the association, attended one of the first meetings four decades ago.
She told the Recorder: "The aims of the association are to improve the lives of people with diabetes and to work towards a future without diabetes.
"Over the years we have helped people who not only have the condition, but also their family and carers.
"You do find that sometimes a parent will have it and their child too, as it just so happened to be the case with myself and my mum."
Debbie has been chairwoman of the association for three years.
"We've always tried to be there for the community and to be a sort of support network," she said.
"The fact that we're still in existence after 40 years is quite an achievement.
"There aren't many groups out there.
"We can't give out medical advice but we do have a table of free literature for people to look at our meetings covering Type 1 and Type 2 diabetes.
"For the last three years, we have tried to have all of our speakers as medical speakers."
The technology around managing diabetes has made significant changes.
Debbie remembers a time going back 40 years when people with Type 1 diabetes used glass syringes to administer insulin.
"Now we have disposable syringes, insulin pens and insulin pumps," she said.
"Things have moved on so much with the research."
Secretary of the Havering group, Ann Prescott, added that she is now able to use a Freestyle Libre device which provides instant glucose readings. This method of testing avoids constant finger pricking to get a blood glucose reading.
"It has advanced greatly as far as the technology is concerned," said Ann.
"More and more people are getting this condition.
"It's quite a shame because the help is out there but it isn't always reaching people."
Havering Diabetes Group has invited the mayor, founder of the Havering group Peter Scott, former president of Diabetes UK Richard Lane and the current chief executive of Diabetes UK Chris Askew, to their celebratory dinner next month.
Contact Ann Prescott on 01708 935779 or visit havering.diabetesukgroup.org.
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