Nutrition to Reduce Cancer Risk: Beyond the Headlines
This blog content is re-published with permission from Smart Bytes®, a blog by Karen Collins, an expert on nutrition to reduce cancer risk.
It’s easy to feel overwhelmed by today’s headline hype about nutrition to reduce cancer risk. The good news is that your nutrition and eating habits can help lower your risk of cancer. Instead of feeling like you’ve got to do it all and eat “perfectly”, you can set priorities and focus on choices that are likely to make the most difference.
A plant-focused diet simply means that plant foods are the largest part of your plate — not necessarily your whole plate. This includes vegetables, fruits, whole grains, legumes (dried beans and peas, lentils and soy foods), nuts and seeds. Why are these foods a core part of recommendations to reduce cancer risk?
- Dietary fiber: Some kinds of fiber are prebiotics and may help nurture healthy gut bacteria reduce chronic, low-grade inflammation that can set the stage for cancer development. There are other types of fiber bind harmful substances, reducing the body’s exposure and helping the body eliminate them. Other kinds of fiber may support healthful levels of certain hormones.
- Antioxidant protection: Some nutrients, such as vitamin C, vitamin E, and beta-carotene, are antioxidants that help calm oxidative stress before it can damage DNA and ignite inflammation. Polyphenols, including flavonoids and other natural plant compounds, are not antioxidants themselves (despite what you see in headlines based on studies in isolated cells) – they are metabolized to other compounds that seem to turn on the body’s own antioxidant defense system.
- Cancer-inhibiting cell signaling and gene expression: Natural compounds from plant foods may also affect signals sent between cells that regulate growth cycles and promote self-destruction of abnormal cells. Evidence suggests they can change expression of genes that control activation and de-activation of carcinogens, tumor suppressor genes, and more.
Examples include: allyl sulfur compounds from the garlic-onion family; isothiocyanates from cruciferous vegetables (broccoli, arugula, cauliflower, Brussels sprouts, bok choy, cabbage and more); carotenoids (yes, beta-carotene is part of a whole family – lycopene in tomatoes and watermelon, alpha-carotene in carrots and winter squash, lutein in greens and corn, beta-cryptoxanthin in red pepper and oranges); and polyphenols from berries, citrus fruit, whole grains, and nuts.
- Prebiotic benefits we get from certain types of dietary fiber — nurturing health-supporting gut bacteria — also seem to be provided by some polyphenol compounds.
Limit Red and Processed Meats
Plant-focused eating has room for other foods, too. Just choose them wisely. Limiting red and processed meats helps protect against colorectal cancer, the third most common cancer in the U.S.
- Red meat: Choosing lean cuts of red meat is a good start, especially for heart health. Note that all red meat is higher than poultry or seafood in heme iron, which can lead to free radicals that damage DNA and formation of cancer-linked compounds within the gut. Emerging evidence also ties diets high in red meat to changes in gut bacteria that seem to promote inflammation. If you enjoy beef, lamb and pork, keep it to no more than 12 to 18 ounces a week – which is about 4 to 6 portions the size of a deck of cards.
- Processed meat: Meat that is smoked, cured, salted or has added preservatives seems to increase colorectal cancer risk even more than other red meat. So if choices like bacon, sausage, and hot dogs are frequent parts of your meals, let’s consider other options.
- Swaps for red and processed meats: Chicken or turkey is one option. Heart-health recommendations advise eating fish twice a week; so swapping red meat for fish brings a double-win. Pulses — dried beans, peas and lentils — provide a double-benefit when you swap them for excess meat, too, since they are powerhouse sources of dietary fiber and prebiotic compounds.
Plant-Based Alone Doesn’t Equal Healthy: Although highly processed foods like chips, crackers, and cookies may technically be plant-based, these foods won’t provide the health benefits you get from minimally processed foods. Be aware that excess calories can add up quickly with frequent use of sweets, processed snack foods, or sugar-sweetened drinks (whether sweetened tea”, soft drinks, or syrup-laden coffee drinks).
Aim to be a healthy weight throughout life. If, like most Americans, you’ve been gaining a little weight each year, it makes sense to make a few habit tweaks to stop the gain. And even a small weight loss that is maintained makes a difference in inflammation and hormones that promote cancer development. Plant-focused eating includes substantial portions of foods that are filling without being high in calories, helping you shave calories without going hungry.
Our eating choices can make a difference in cancer risk. There are many approaches to this healthy “plant-focused” eating. Whichever path you choose, the healthfulness of your eating is not based only on what you don’t eat, it’s also about what you do eat. Experiment with some small changes today and find those that are doable for you.
Karen Collins, MS, RDN, CDN, FAND is a consultant, speaker, and writer who specializes in helping people make sense of nutrition news about heart health and reducing cancer risk. You can follow her blog, Smart Bytes®, through her website and follow her on Twitter and Facebook.