When it comes to fighting cancer, the good news is that many kinds are subject to delay or avoidance by making smart lifestyle choices. Some of the behavioral tweaks recommended by a leading cancer doctor might surprise you.

Of course, the formula for preventing cancer isn't ironclad, nor is it one size fits all. That's according to Dr. David Agus, an oncologist, professor of medicine at the University of Southern California in Los Angeles and author of the new book "The End of Illness," which examines the scientific evidence behind his conclusions. "As a cancer doctor on the front lines, one of the first things you realize is the best way to treat cancer is actually to prevent it," he said.

KEEP A PREDICTABLE SCHEDULE

Try to eat, sleep and exercise at about the same time every day, and don't forget to schedule downtime to unwind without technological intrusions. Getting enough shuteye is important for memory consolidation, mood balance and long-term physical health, he says, but regularity of sleep patterns matters more than total hours slept.

Having trouble adhering to a routine? Get a dog, he suggests. That involves walking and feeding it at regular intervals, forcing people to stick to the clock, get physical activity and take breaks from working.

MOVE FREQUENTLY

Fitness is paramount to your body's overall functioning, and you won't have to sweat the risks of pills or surgery. What's more, sitting for long stretches of time has been linked to a higher risk of early death and many diseases, including colon cancer. Aim for an hour of moderate exercise a day (short bouts count, too), Agus says, and keep a set of free weights nearby so you can sneak in biceps curls.

CONSIDER A DAILY ASPIRIN

If you're over 40, talk with your doctor about the benefits and risks of taking a statin and low-dose daily aspirin if you're not taking them already, he says. These low-cost medications have been shown to reduce the risk of heart attacks, strokes and even some kinds of cancer, but they also have side effects you should weigh carefully.

GET AN ANNUAL FLU SHOT

Having the flu triggers inflammation, which can set the body up for serious problems when it's most vulnerable, he says. The flu vaccine, whose contents change every year according to the dominant viral strains projected to circulate, helps the body tone down its harsh immune response. "I want [people] to think of a flu shot in terms of not just what it means today but a decade from now," Agus said.

DITCH THE VITAMINS

Unless you're addressing a confirmed vitamin deficiency, are considering pregnancy or are already pregnant, steer clear of multivitamins and save money without sacrificing your health, Agus says. Some people believe they need supplements to fight so-called free radicals, but the body already has defenses against such byproducts of metabolism, he says, and the effects of interfering with the body's natural control system aren't well understood. Many studies point to no benefit and sometimes harm from vitamins and supplements. Taking vitamin E, for example, was found to raise the risk of prostate cancer 17 percent in healthy men, according to a study published in the Journal of the American Medical Association.

WEAR COMFORTABLE SHOES

Nix the high heels and other uncomfortable footwear in favor of shoes that don't cause swelling or curtail your movement, Agus says. Picking shoes that won't cause back or joint problems can help you cut your risk of chronic inflammation. "Over weeks, months, years, [wearing comfortable shoes] changes your overall health, and you're also going to move more," he said.

ASSESS YOUR MEDS

Take inventory of your medicine cabinet once a year. Go over your list of drugs with your doctor to see if your needs have changed and if you can lose at least a few of them. "Health is a constantly moving target," Agus said.

CASH IN ON HEALTHY LIVING

Your employer might offer lower insurance premiums in exchange for taking a health-risk assessment or cut you a break on the cost of a gym membership. Your premium dollars might include the services of a health coach, who can help you set and stick to goals around making sustainable lifestyle changes. "How do we make health profitable instead of sickness?" Agus said. "Put in incentives for prevention."

KNOW YOURSELF

Keep records of your medical data. Perhaps Agus' most controversial tip is to store it online, but old-fashioned paper will do. If you jot down dates, symptoms and treatment trial and error, it might allow you to discover patterns that can help you and your doctor catch problems early and customize your care more effectively.

RETHINK YOUR DOCTOR

Think of your doctor as a partner, not a friend. Ask your physician what he or she does to stay current on the latest scientific information, Agus suggests. If you don't feel you can tell your doctor anything, find a new one.