Type 2 diabetes, cardiovascular disease and liver disease are the biggest conditions that kill us, and in May this year, the largest ever screening was held when more than 400 people were tested to see if they were at risk from them.
Some famous faces got involved too, as Benidorm star Crissy Rock, ex-EastEnder Ricky Groves and West End singer Jodie Prenger were all tested.
The results are pretty shocking and Dr Phil has to help Ricky understand what his liver must go through to process fatty food. He shows Jodie what happens if the body can't absorb sugar from the blood stream and teaches Crissy about cholesterol.
Long Live Britain, BBC1, 9pm & 10.35pm
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