Im aware that red meat and processed meat causes cancer. apparently also foods preserved by salting causes cancer. what kind of foods are preserved by salting? is it any food that has salt in the ingredients or specific foods like smoked salmon?

Salt does not cause cancer. You can reduce your risk of cancer by adopting healthy habits: Eat a mostly vegetarian diet, avoid alcohol, tobacco and street drugs, avoid excessive exposure to sun, maintain healthy weight, get HPV vaccine, exercise 30 minutes each day, drink enough water so your urine is mostly colorless. Wish you good health!

Cancer can be caused by many chemicals and infections as well as overweight conditions(excess of body fat is a contributor). As for preservatives, it is not healthy to eat old preserved foods whether these are meats or non-meat foods. So you should eat fresh foods( ample amount of vegetables and fruits. The rest should be fish, grains and proteins from plant nuts and eggs and low fat dairy.

The healthiest diet is the DASH diet. Move to it as it meets the guidelines of the American Cancer Society guidelines likely to prevent cancer. But check with UK Cancer Society guidelines as they may be more appropriate for you. I would also move out of London due to air pollution. And do not smoke or be around those who smoke.