By Dr. Richard Beliveau
While we still have a poor understanding of why industrialized countries such as our own have such high rates of breast cancer, many different studies have shown that what we eat is a major risk factor for developing the disease.
One recent study suggests that the kind of fat we include in our diets could play a key part in this increased risk.
Several population studies have also linked high-fat diets to a higher risk of developing breast cancer. The effect is especially apparent in the case of trans fat, the synthetic fat that is produced through hydrogenation and is found at especially high levels in packaged foods. These studies show that women who eat more trans fats double their chances of developing breast cancer.
However, it’s important to keep in mind that not all fats were created equal: some types, especially the monounsaturated fats found in olive oil and the omega-3 polyunsaturated fats in flaxseed, have many positive effects on health.
The increased breast cancer risk associated with a high-fat diet therefore depends not only on quantity, but particularly on the kind of fat you eat.
Spanish researchers examined the impact of different fats on the development of breast cancer by comparing the effect of a diet high in either extra virgin olive oil (a source of monounsaturated fats) or corn oil (a source of omega-6 polyunsaturated fat). The researchers gave animals doses of the powerful carcinogen 7.12-dimethylben(a)anthracene, and looked at the impact of the two kinds of fats on the resulting breast cancer. The team then compared the results to those in a low-fat control diet (2).
The Spanish scientists observed that breast tumours in animals fed a diet high in corn oil were more numerous and developed more quickly. On the other hand, those animals given diets with olive oil had fewer tumours that developed at a much slower rate. These differences seem to be linked to the diametrically-opposed effects of these fats on several processes involved in breast cancer cell function. For example, whereas a diet high in corn oil stimulates certain key proteins that help cancer cells spread uncontrollably, the diet based on olive oil reduces the activity of these proteins and encourages cell destruction through apoptosis.
Scientists are still unsure exactly what cellular mechanisms are responsible for these effects, but the final results are no less impressive: it’s possible to considerably modify the aggressiveness of breast cancer cells by simply using olive oil as a fat.
Monounsaturated fats as well as phenolic compounds (phenols) found in extra virgin olive oil have long been recognized as an essential way of preventing cardiovascular disease. This latest study of breast cancer risk shows us that olive oil does far more than just promote heart health, and actually plays a major role in preventing chronic disease in general.
* * *
Cranberry and Flaxseed Muesli
This is what my breakfast has looked like for the past 30 years. This muesli will keep for a month if it’s kept in an airtight container at room temperature. I recommend taking a few little bags of it on walks. It’s a nutritious mix that will help you shrug off the temptation of fast food.
7 cups (630 g) rolled oats
2 cups (240 g) sunflower seeds
1/2 cup (125 ml) olive oil
3/4 cup (150 g) buckwheat honey
1/2 cup (60 g) sesame seeds
2 cups (240 g) slivered almonds
1 Tbsp. freshly-ground flaxseed per portion
1/4 cup (50 g) dried cranberries per portion
Milk to taste
Preheat the oven to 190 C (375 F). Combine the oats, sunflower seeds, olive oil and honey in a large baking tray. Sprinkle the sesame seeds over the mix.
Bake uncovered in the oven. Mix every five minutes in a convection oven or every 20 minutes in a regular oven. When the contents start to brown evenly, add the almonds and keep baking until everything is well-browned.
Remove the mixture from the oven and let it cool completely before pouring into airtight glass or metal containers. Add the flaxseed, cranberries and milk to each bowl when serving.
Recipe: Dr. Richard Beliveau