As World Cancer Day rolls around again, it’s striking – and frankly, more than a little dispiriting for us cancer educators – to see how little people know about the disease. Not about the actual disease – for cancer is a complex condition that baffles even researchers and oncologists – but about the risk factors that influence whether we get cancer or not.
A survey commissioned by American Institute for Cancer Research (AICR), published today, revealed that too many Americans still cling to the myth that they are powerless before cancer. The full details of the survey can be found here, but the section of the survey I’d like to examine more closely here concerns diet.
Asked whether “diet affects people’s risk of getting cancer,” just over half of Americans surveyed (58%) knew that they can indeed cut cancer risk with a healthy diet, but far too many either disagreed (11%) or could not make up their minds (31%).
Meanwhile, when asked whether “body weight affects people’s risk of getting cancer,” the answer was “alarmingly low,” according to the AICR: less than half (41%) of those surveyed knew that body weight has an impact on cancer risk. One in 5 (20%) disagreed, while 38% could not make up their mind.
UK respondents surveyed by the World Cancer Research Fund International were even less informed: 49% of people polled said they didn’t know that diet can affects people’s risk of getting cancer. Two thirds of the 2,000 British adults polled did not know about the links between cancer and physical activity and 59% were unaware of the correlation between cancer and body weight. Lastly, more than a third of Brits polled (34%) believe that the chances of getting cancer are mainly due to a family history of the disease, even though only 5-10% of cancers are linked to genes.
“On World Cancer Day 2014 it’s very alarming to see that such a large number of people don’t know that there’s a lot they can do to significantly reduce their risk of getting cancer, said Amanda McLean, the World Cancer Research Fund’s General Manager.
In fact, approximately 374,000 cases of the most common cancers could be prevented each year in the US by eating a healthy diet, being physically active and staying a healthy weight, the AICR estimated. That means an estimated one of three cancers would never have to happen.
Excess body fat is a cause of seven cancers, including post-menopausal breast, endometrial and esophageal. Carrying excess body fat causes an estimated 117,000 U.S. cancer cases each year, the AICR estimates. Meanwhile, research has shown that 30 minutes of daily moderate activity can help reduce cancer risk independent of weight.
Mediterranean diet to the rescue
You don’t have to become a cancer specialist to lower your risk of developing the disease. At the risk of sounding like a broken record, all you need to do is to adopt a Mediterranean diet and a moderate exercise routine, and you will lower not only your chances of developing cancer, but also heart disease, diabetes, Alzheimer’s disease, osteoporosis and various other diseases of “civilization.”
Again and again studies show that the Mediterranean diet lowers the risk of cancer. There are various ways in which this way of eating works against the development and spread of cancer cells.
1. Antioxidant, anti-inflammatory and anti-angiogenic compounds: The Mediterranean diet brims with foods that have antioxidant and anti-inflammatory properties, such as vegetables, oily fish, legumes, fruits, spices, herbs, nuts, seeds and or course olive oil. Antioxidants protect our cells, and the genetic information inside them, from free-radical attacks that could otherwise lead to cancerous cell change.
Inflammation, meanwhile, is another factor that can promote the development and growth of cancer (read more about inflammation and cancer in this excellent article by Dr. Lawenda).
Lastly, angiogenesis – the growth of new blood vessels that tumors need in order to grow – can be slowed or halted by eating foods that abound in the Mediterranean diet, such as berries, citrus fruit, grapes, kale, artichokes, squash, parsley, garlic, tomato and olive oil (find out more about antiangiogenic foods in this brilliant TED talk by William Li M.D. of the Angiogenesis Foundation).
Red wine – the favorite dinnertime beverage in the Mediterranean region – contains powerful antioxidants too, but since alcohol is thought to promote cancer, I recommend abstinence or, at best, extremely moderate red wine consumption to anyone wishing to lower their cancer risk – at the very most, 1 glass per day for women and 2 glasses for men, the AICR’s recommendation.
2. Low glycemic impact: As is increasingly understood, carbohydrates that push our blood glucose levels sharply higher also increase our risk of developing cancer and can fuel the growth of tumors that are already present. This is not only because sugar is a favorite source of energy for cancer cells, but also because every time our blood-sugar levels rises, our body produces insulin and insulin-like growth factor (IGF-1), which both fuel the growth and spread of tumors.
This doesn’t mean you can’t ever eat carbohydrates; however, it’s best to choose those that are converted into blood glucose slowly, such as whole grains and low-glycemic fruits and vegetables – and to avoid those that are released rapidly into the blood stream, such as candy and sweetened drinks, and anything made with refined flours, such as cookies, cakes, and convenience snacks.
To further lower the glymemic impact of the carbohydrates you eat, it’s important to eat protein and fat with any starchy food. The presence of fiber and acidity – for instance, a salad dressing containing lemon or red wine vinegar – further reduces the glycemic impact of starchy foods.
The Mediterranean diet has a moderate glycemic impact: it is rich in slowly digested whole grains, vegetable fibers, healthy fats, proteins and blood-sugar-balancing micronutrients, all of which work together to produce steady blood sugar and insulin levels.
3. Healthy fats: While the “standard American diet” (SAD) is dominated by omega-6 fats that fuel weight gain, inflammation and cancer cell growth, the Mediterranean diet contains relatively more anti-inflammatory, anti-cancer omega-3 fatty acids (found in oily fish, walnuts, flax seeds, green leafy vegetables and the eggs, dairy and meat of grass-fed animals) and comparatively fewer omega-6 fats. Moreover, the olive oil consumed around the Mediterranean basin provides healthy monounsaturated fatty acids as well as antioxidant and anti-inflammatory polyphenols thought to have significant anti-cancer effects.
4. Stress-free and life-affirming: Unlike other health-food regimes – for instance, vegan, low-fat, raw-food, low-carb or Paleo diets – the Mediterranean diet does not require you to cut out entire food groups or spend hours preparing complicated dishes. This makes it a simple, stress-free and guilt-free way of eating that’s easy to maintain over the long term.
It does require a modest investment of time into shopping and cooking, but if you can learn to see this as a creative outlet, rather than a dreaded chore, preparing meals and sharing these with people you love can become a source of joy and positivity in your life. Indeed, for some of my clients, cooking the daily meal has become a form of mindfulness practice they find refreshing and life-affirming.