Image copyright Science Photo Library

Too much alcohol and sugar is causing a global "tidal wave" of cancer, says the World Health Organization. It predicts the number of cancer cases will reach 24 million a year by 2035, but half could be prevented. BBC News website readers have been sharing their experience of dealing with cancer.

Simon Bush, ski instructor and pilot, London

I am 53 and have aggressive prostate cancer. I have been extremely active and have never eaten processed foods having always tried to eat a healthy mainly vegetarian diet. I drank wine most days but usually a glass or two. I had no symptoms at all - just one incident of blood. I thought I had a kidney stone. Luckily I had a very quick diagnosis.

Image copyright Simon Bush Image caption Simon Bush says he was lucky to have a quick diagnosis

Everyone was very surprised I have cancer. I can never understand why people don't lead healthy lives as they will feel better but it does not mean you won't get cancer. I've had hormone and chemotherapy, and am undergoing radiotherapy. I was a ski instructor and an airline pilot so cannot work at the moment.

Everywhere I look there is cancer. I feel great at the moment. I ran four miles last week. My brother is doing a half marathon in April. He's raising money for cancer research. I hope to join him but it depends on how I feel during radiation therapy.

Vicky Neeson, Glasgow

During the diagnosis period, clinicians assumed my 19-year-old son smoked and drank and - because he went to the gym - that he was a steroid abuser. They even suggested he may not be telling me the truth about his life style. Yet, he is the most health-conscious person I know.

Image copyright Vicky Neeson Image caption Vicky Neeson says she had to persist to get her teenage son diagnosed

There was scepticism because he was a teenager and therefore they thought his ill-health was due to his own behaviour. It was cruel enough to have a disabled child get such an awful disease. But to have doctors try to find some reason that it was his fault was just truly awful. I had to go through a few clinicians and plead for blood tests. They don't concentrate on people with disabilities having cancer. Eventually he was diagnosed with Hodgkin's disease.

Hugh, Darwin, Australia

I'd always lived a very simple, healthy lifestyle. I have one low-calorie beer every three months. 20 years ago I used to smoke five cigarettes a day but I stopped that a long time ago. I've never used drugs. Then one day, after a routine check-up, I was told by doctors that I was suffering from a rare form of cancer. Only four people have it in the world. I was given only three months to live. I never believed I was sick. I didn't do anything wrong. It was a big shock.

I'm happy with the healthy life I have

An operation was performed and I lost my left kidney, the gall and 30% of my pancreas. Nine hours later I was sent to intensive care. A few weeks after I suffered an infection in the area where my kidney was removed which almost took my life again.

It was six months before doctors released me. Some doctors recommended chemo treatment but in the end, it was not used.

While there's a 50% chance that I'll get the cancer again, I've been diagnosed as "free of cancer" for the last two years. I still maintain a healthy lifestyle. I'm happy with the healthy life I have. Four times a week I swim 31 laps in an Olympic-sized swimming pool. I can do it in 45-50 minutes. People often tell me that I look younger than my 69 years of age. It is thanks to doctors, nurses and my family that I am still alive.

Jun Terasawa, Yokohama, Japan

I do not smoke, I'm not obese, and I've never been a heavy drinker. I do regular exercises every week (that is, walking up to 11 kilometres in the countryside). Yet I've become a cancer patient. Doctors in Tokyo diagnosed my illness as lymphoma in January 2013. I went through treatment in May. It seems that the treatment was successful. I am completely clear now but this report is misleading. In my experience it wasn't smoking or alcohol or obesity that gave me cancer.