The American Institute for Cancer Research recommends that at least two-thirds of your plate be filled with foods that come from plants. (marilyna/iStock)

Everyone knows someone who has been through cancer. My father was diagnosed with colon cancer when I was 14 years old and died when I was 17. It was and still is a devastating loss. Ever since, I’ve been passionate about researching the nutrition and cancer connection.

Data from the Centers for Disease Control and Prevention and the National Cancer Institute suggest that 45 percent of cancer deaths are because of risk factors we can control, including smoking, drinking too much alcohol and eating a poor-quality diet. Rumors are always circulating that certain foods can cure cancer, but the truth is you need to eat a variety of potentially cancer-fighting foods to reduce your risk. And most of these foods are plants.

Choose a plant-based diet

The American Institute for Cancer Research recommends that at least two-thirds of your plate be filled with foods that come from plants, such as vegetables, fruit, pulses and whole grains. The remaining portion can include foods that come from animals such as fish, poultry, meat, eggs and dairy products. Plant-based diets may help prevent cancer for a plethora of reasons. For one, plant-based foods contain fiber, which is needed for a healthy digestive system and promotes a healthy gut microbiota, a key part of your immune system.

Vegetables, fruit and other plants also contain phytochemicals, compounds which protect your cells from damage that can progress to cancer. Just like your investment portfolio, with phytochemicals you want to diversify for the best results. Eat a minimum of 2½ cups of vegetables and fruit every day in a variety of colors and you’ll be on your way to reducing your cancer risk.

There has been some public concern that soy may increase the risk of hormone-related cancers. Soybeans contain isoflavones, compounds that are similar to the hormone estrogen but much weaker. Overall, research suggests that soy doesn’t increase cancer risk and may even reduce the risk of prostate, breast and gastrointestinal cancers. My advice for soy is the same as my advice for all foods: Choose whole foods that are minimally processed. Go for soybeans (edamame) or tofu rather than mock meats made out of heavily processed soy and often loaded with preservatives.

Limit processed and red meats

Red meat contains compounds that can damage intestinal lining and may increase cancer risk. But it’s all about how much you eat, and your overall diet. Eating more than 18 ounces of beef, pork and lamb a week is associated with a higher risk of colorectal cancer, so keep your amounts below that. To help you visualize, three to four ounces of meat is the size of a deck of cards, so you could have that portion five times a week. If you want a larger portion, have red meat less often.

Whether bacon or hot dogs or deli meats, processed meats contain preservatives that, when eaten regularly, increase your risk of stomach and colon cancers. If you enjoy processed meats, have them only on special occasions.

Watch your alcohol intake

Wine — especially red wine — contains a phytochemical called resveratrol that may boost heart health. But drinking any type of alcohol, even in small amounts, is linked to higher breast cancer risk. If you do drink, limit yourself to two drinks a day for men and one drink a day for women. And take a look at how generous your pour is. A standard drink is 1½ ounces of spirits, five ounces of wine or 12 ounces of regular beer.

Choose food over supplements

There always seems to be a new herb or supplement rumored to prevent cancer. The research often isn’t there to back up these claims, and it’s best to try getting your nutrients from food first. That way you’re getting a variety of nutrients that often work better together. Getting too much of certain nutrients can increase your risk of some cancers — for example, smokers who take vitamin A supplements could be increasing their risk of lung cancer. It’s tough to overdose on nutrients in food vs. supplements. Always talk to your doctor and dietitian before adding supplements to your routine.

Trim excess body fat

Excess body fat, especially around the midsection, appears to increase the risk of about a dozen different types of cancer. You might think of fat as an inert substance, but it’s an organ that affects hormone levels and releases substances that can increase inflammation and cell division, creating an ideal environment for cancer to develop. That’s why getting to a healthy weight (and doing it in a way that gives you all of the potential cancer-fighting nutrients you need) is one of the most important things you can do to lower your cancer risk.

You don’t have to be perfect with your diet. Even if you are, that doesn’t guarantee you’ll be cancer-free forever. Eating as healthfully as possible reduces your cancer risk, and occasional indulgences minimize stress and are part of socializing with the people you love. Reducing stress could be cancer-fighting, too.

Christy Brissette is a dietitian, foodie and president of 80TwentyNutrition.com. Follow her on Twitter @80twentyrule.