Charity group Diabetes UK ran the event at Cascades shopping centre offering advice on the condition.
More than 600 leaflets were given out and 110 people had their waists measured to see if they were at risk of the disease.
The charity's 'meas
ure up' campaign aims to raise awareness among people with large waists who are to 12 times more likely to develop the condition.
Jill Steaton, Diabetes UK's south east regional manager, said: 'Diabetes is one of the biggest health challenges facing us today.
'It's frightening there are more than 65,000 people in the south east alone who have Type 2 diabetes but have no idea they do. It's encouraging so many people came to the Portsmouth roadshow.
'Hopefully they learnt about the condition, its risk factors and how a healthy lifestyle encompassing a good diet and regular physical activity can help prevent and manage Type 2 diabetes.'
There are more than 325,000 people diagnosed with diabetes in the South East, and another 65,000 who have the condition but don't know it. If untreated, it can lead to fatal complications including heart disease.
At-risk waist measurements are 37 inches or more for men, except those of South Asian origin who are at risk at 35 inches or more, and 31.5 inches or more for all women.
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