The expression "you are what you eat" takes on new meaning when it comes to preventing breast and other cancers. Earlier this year, the American Institute of Cancer Research announced that about one third of the most common cancers in the United States are preventable through proper diet, physical activity and weight management. More specifically, 38 percent of breast cancers are preventable with healthy lifestyle choices.

Although genetics do influence your risk for breast cancer, only about five percent of all breast cancer cases occur in people who inherited the altered gene. So, the lifestyle choices you make can really make a difference in reducing your own cancer risk.

What to eat

Mom was right when she told you to eat your veggies. Experts recommend that your diet consist of about two-thirds plant-based foods, including fresh fruits and vegetables, whole grains, nuts and beans. Mother Nature has made it easy for us to consume a wide variety of essential vitamins and minerals: she presents us with fruits and vegetables in a veritable rainbow of colors. Each color contains specific super nutrients so try to eat as many different colors as you can.

The amount of fruits and vegetables you should eat depends on your age, gender and activity level. A 30-year old, moderately active woman (exercises 30 to 60 minutes per day) should strive for two cups of fruits and 2.5 cups of vegetables daily.

A healthy cancer-prevention diet also includes small quantities of lean meats, poultry, fish, eggs and low-fat dairy products.

Fruits and vegetables are packed with vitamins, minerals and phytochemicals (biologically active compounds) that interact together to provide extra cancer protection. These foods are also low calorie and fiber dense, so you feel full after eating and are more likely to maintain a healthy weight. Excessive body fat increases your risk for several types of cancer, including breast cancer.

Here are a few standout foods experts recognize for their cancer prevention properties.

  • Berries (especially blueberries, which are packed with antioxidants)
  • Cruciferous vegetables such as broccoli, cauliflower and cabbage
  • Dark green leafy vegetables
  • Flaxseed
  • Garlic
  • Grapes and grape juice
  • Green tea
  • Soy
  • Tomatoes

What NOT to eat

Try to avoid anything processed-food products with ingredients you never heard of or can't pronounce-and foods that are high in sugar, salt, cholesterol and saturated fats. They all work against you in preventing cancer. Limit your consumption of red meat and alcohol raises, which raises your estrogen levels and increases your risk of breast cancer.