Football legend Sir Alex Ferguson has spoken of the "devastating impact" of lung cancer at the start of a campaign to improve early detection of the disease.

The former Manchester United manager, who lost both his parents to the cancer, appears in a new advert telling people how an early diagnosis can give people extra time to spend with their loved ones.

The campaign is part of the Scottish Government's £30 million programme designed to increase the number of cancers that are diagnosed early.

Sir Alex said: "I wanted to be involved in this campaign as I lost both my parents to lung cancer. I know the devastating impact cancer can have on families."

His father Alexander died from lung cancer in 1979 and his mother Elizabeth died from the disease in 1986. Both were in their 60s.

Sir Alex said: "Cancer's not what it used to be and there are now treatments that can save or extend your life. So rather than doing nothing about it, I urge anyone who is worried to get checked as early as they can."

Lung cancer kills more people than any other cancer and Scotland is said to have one of the highest rates of the disease in the world, with fewer than 9% of patients still alive five years after diagnosis.

Figures released earlier this year show that 5,069 people were diagnosed with the disease in 2011, which is 17% of all cancer diagnoses for that year.

The campaign adverts are being screened on television from today, with Health Secretary Alex Neil saying he believes they will encourage more people to come forward and be checked.

"Lung cancer is the most common cancer in Scotland and this new advert encourages people to get checked early if they have a persistent cough or cough that has changed, or any concerns," he said as he met with three lung cancer survivors.

"Lung cancer is much more treatable than it used to be. The earlier lung cancer is detected, the easier it is to treat and the better the chance of a successful outcome.

"More lives can be saved in Scotland through earlier detection. It is great to have such a recognisable face to front the campaign, and I'm sure Sir Alex Ferguson's story will help to encourage people to get themselves checked early.

"This advert is part of our £30 million Detect Cancer Early plan which is initially focusing on breast, bowel and lung cancer and aims to increase the early detection of cancer by 25% by the end of 2015."

Lung cancer survivors echoed the message that people should contact their doctor if they have any concerns about the disease.

Jennifer Chapman, 55, from Aberdeen, was diagnosed with the disease, which killed her father, 13 years ago. She went to her GP because she had a persistent cough on holiday.

The primary school teacher has endured chemotherapy, an operation to remove part of her lung and radiotherapy for a secondary brain tumour that developed later as a result of the lung cancer.

"I'm still here, 13 years after being initially diagnosed. I shouldn't have been here six months after being diagnosed but I am. And I live a very happy, fit life. It's so important to go to your doctor with any concerns about your chest; the earlier the better as it could save your life," she said.

Bill Cubard, 70, from Dunblane, was also diagnosed with the disease this year after going to see his GP because he was experiencing a bad wheeze at night.

He said that inoperable lung cancer was diagnosed soon afterwards, recalling: "When I heard that it was cancer the bottom fell out of my world. My dad died of lung cancer when he was just 39 years old so I automatically feared the worst. Breaking the news to my family and friends was particularly difficult."

But in February 2001, after undergoing chemotherapy and radiotherapy, Mr Cubard was told the cancer had gone.

"Being diagnosed with cancer will always be a big deal and a huge worry but if it's caught early enough, you stand a much better chance of survival," he said.

"It's normal to be frightened of cancer but early detection really does make a difference to your options and outcome. Whether it's a lump or a persistent cough, you should always get it checked by your doctor. In most cases, it's nothing to worry about, but it could save your life."

John Hughes, 64, from Blantyre, has been clear of lung cancer for almost seven years.

The former smoker was found to have the disease after coughing up blood.

"I was totally distraught when I found out as my father had died of lung cancer. And back then, knowing you had a lung cancer was a death sentence. It really plays havoc with your mind. And the worry you feel when you hear; you think your shot at life is over. My wife and son were devastated."

Mr Hughes underwent chemotherapy to shrink his tumour and had his lung removed and radiotherapy treatment to ensure the cancer did not spread.

"Cancer is a different disease and you shouldn't lose hope if you're diagnosed with lung cancer. If doctors can't cure you, they'll be able to help in some way," he said.

Health campaigners also backed the new campaign.

Lorraine Dallas, director of information and support at the Roy Castle Lung Cancer Foundation, said the chances of survival are "sadly very poor" for people with lung cancer if it is not caught early.

Three-fifths of people are diagnosed when the disease is so advanced that there are few treatment options left, she said.

"This is why the Detect Cancer Early campaign is so important because the earlier people are diagnosed, the more chance they have of surviving," she said.

Dr James Cant, head of the British Lung Foundation in Scotland, said: "Lung cancer is a disease which can develop slowly over a number of years. Often it causes no pain so it's important to be aware of other warning signs and act quickly to have them checked.

"A persistent cough or coughing up blood could be symptoms of lung cancer or another lung condition. If you experience any of these symptoms contact your GP. Whatever you do, don't ignore them. Don't get scared, get checked."

Gregor McNie, Cancer Research UK's public affairs manager in Scotland, said: "People are often put off from going to the doctor by the fear of what might be found. But if it is lung cancer, getting it diagnosed and treated early could make a real difference. When cancer is diagnosed at an early stage, treatment is often simpler and more likely to be successful.

"Sir Alex Ferguson is a hugely influential figure and we hope that his involvement in the Scottish Government's Detect Cancer Early programme will encourage people to take a positive step and make what could be a life-saving appointment with their doctor."

The new adverts with Sir Alex come after actress and comedian Elaine C Smith starred in a successful breast cancer awareness campaign, while Still Game star Ford Kiernan provided the voice for an advert encouraging people to get tested for bowel cancer.