Vanessa Williams's heartbreaking diagnosis after grandmother's ...

American actress and singer Vanessa Williams previously opened up about her struggle with type 1 diabetes. The Desperate Housewives and Broadway star, who is appearing on the Graham Norton Show on Friday night, discussed the heartbreaking effect the condition had had on her family as her grandmother died 'early' from the same condition.

Type 1 diabetes causes the level of glucose (sugar) in your blood to become too high, according to the NHS. It happens when your body cannot produce a hormone called insulin, which controls blood glucose.

Those who have the condition have to take insulin every day to keep their blood glucose levels under control. Vanessa and her mother Helen co-authored a memoir titled You Have No Idea, published in April 2012, discussing her rise to fame and personal struggles, including life with type 1 diabetes.

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Vanessa, who had to renounce her title of Miss America pageant winner after she posed nude in Penthouse magazine before later receiving an apology, actively supports charities that fund diabetes research, notably the Stay Well Foundation for diabetes care in Guam.

Speaking at an event for a charity she spoke about the devastating loss of her grandmother after she stubbed her toe. She said: "I am here first and foremost because I lost my grandmother to complications of diabetes when she was 64. She stubbed her toe, she lost her toe which eventually led to her losing her leg underneath her knee.

"She suffered complications of heart disease which was also exacerbated by her diabetes and we lost her as a young woman. She was there for me when I won Miss America back in 1983 but she was not there when I was nominated for my first Grammy in 1989.

"She never saw any of my broadway performances and she couldnt attend my wedding because of her complicatioons with diabetes and her early death."