Every time a new year kicks off, we use it as an opportunity to refocus on habits. You might resolve to work out more in 2015, eat less sugar, or cook more often at home. Whatever your personal goals are, changing your lifestyle habits for the better can be even more beneficial than just helping you drop a few pounds or feel healthier and more energetic.According to statistics recently released by Cancer Research UK, about 40 percent of cancer cases in the last five years could have been prevented by simple, healthy lifestyle changes. The most obvious habits that are to blame? Smoking and sun exposure. In fact, in the UK, smoking-related lung cancers accounted for a fifth of all cancer cases in the past five years. In the U.S., skin cancer is the most common form of cancer, and more people die from lung cancer than any other type.Some cancers cannot be avoided, no matter how healthy you are; another recent study attributes two-thirds of initiation — not spread — of cancer to bad luck, meaning random DNA mutations that can’t be foreseen or prevented. But when it comes to things like lung cancer, basal cell carcinoma (the most frequently occurring skin cancer), colorectal cancer, and a few other cancer types, research points to lifestyle habits, genetics and environmental factors as key influencers.So what can you do to reduce your risk? Here are the most important lifestyle habits you need to tweak to reduce not only your cancer risk, but also your risk of other diseases like obesity and diabetes:1. Quit SmokingThis is a no-brainer. Smoking not only causes lung cancer and other diseases like emphysema, but also predictably increases aging of your arteries, making you feel and look eight years older. Twin studies prove how much smoking can age you well beyond your years.2. Stop TanningThere’s a reason the Surgeon General stepped up to the plate to denounce UV rays and issue a call to action for Americans to reduce sun exposure: It causes skin cancer. If you tan in a tanning bed, you’re getting up to 15 times more UV radiation than you would outside in the sun — which is why they up your skin cancer risk so much. Always wear SPF when you go outside, even on a cloudy winter day. Wear a cute sun hat to the beach. Walk on the shady side of the street on a blazing hot August day. You don’t have to become nocturnal, just always practice safe sun.3. Eat More Fruits & VeggiesVitamins, polyphenols, and other nutrients like lycopene, found in fruits and vegetables, can help naturally protect skin from skin cancer. It doesn’t do enough to take the place of sunscreen, but it’ll give you an extra little boost of protection. Plus, the phytochemicals found in fruits and vegetables can protect against cell damage in the body, lowering risks for certain cancers, like prostate and breast cancers.4. Follow a Low-Fat, Anti-Inflammatory DietEpigenetics refers to the science of changing your gene’s expression in ways other than literally going into your genes and changing your DNA. One way this is done is through food. Some research shows it might be possible to ward off cancer and other chronic diseases by following an anti-inflammatory diet. Cruciferous vegetables (like broccoli), fruits high in vitamin C (like kiwis or oranges), foods high in omega-3s (like walnuts and salmon), berries, and some herbs (like curry, ginger and garlic), are all essential in a healthy, cancer-fighting diet. Avoid simple sugars or syrups and non 100% whole grains; follow a low-saturated fat diet, with only healthy fats like nuts and fish; and severely limit your intake of red meats and processed meats — studies have connected these to cancer.This year, take your health into your own hands. Let’s all work together to reduce the diagnosis rate of preventable cancers in 2015, and make it your healthiest year yet!