...does it increase cardiac events and cancer? Does the low-fat Japanese diet protect against cancer? The answers to these questions is not cut and dried. When discussing the so called "American" high fat diet we need to be very careful in categorizing which fats and when discussing the Japanese diet we need to be specific about which cancers. A friend's sister asked a question on her Facebook page regarding traditional diets with traditional fats and I ended up debating (politely) with a friend of hers whom I don't know. However, the talking points she brought up were very familiar, in fact, they are the same ones I hear about all the time. Because they are so common, I thought that I should cover them here.
1. "When we export our high fat American diet to other countries, the rates of cardiac events and cancers sky rocket."
If you mean the standard American diet rife with rancid vegetable oils, oxidized cholesterol, trans-fatty acids, and hydrogenated oils then, yes, of course it does. But then that is because the term "fat" is not monolithic. There are many important fats needed for our metabolism which are known as "essential fatty acids" which we need to consume because we cannot make them in our bodies. A deficiency in these fats can lead to cognitive failures as well as an increased risk of various diseases including diabetes (see HERE). We also need fats in order to absorb some of the vitamins in the foods we eat (see HERE). While it is true that vegetable oils are fats and as such can help with the absorption of vitamins, these can be risky. The consumption of hydrogenated vegetable oil has been demonstrated to be associated with the increased occurrence of cancers such as those in prostate (see HERE). These levels were found by measuring the amounts of trans-fatty acids in our tissues, which always comes from consumption since we cannot produce it in our own bodies. Trans-fatty acids are also found to increase our risk of cardiac events and do so more than saturated fatty acid from any source (see HERE). It is also important to note that saturated fat may not be as bad as you were lead to believe. Coconut oil, which is 90% saturated (compared with lard at 40%), has actually been shown to decrease bad cholestrol (LDL) and increase good cholesterol (HDL) (see HERE). This might not be what you were expecting. While it is true that currently the American diet is full of the dangerous fats, there are many healthful fats available to Americans now. So, while I admit it is the American-ness of the diet, I heartily disagree that it is the fattiness of it.
2. The Japanese have a low-fat diet high in soy and have lower rates of cancer than Americans.
This is is tricky because they do have lower rates of some cancer, specifically cancer of the breast, which seem not to be a matter of genetics. When genetically Japanese move to the United States and indulge in the standard American diet they have they same rates of breast cancer as American while at the same time there has been no findings as to what elements of the diet increases the risk (see HERE). What is more is that cancer is the leading cause of death for the Japanese overall, while there are a few types of cancer for which they have lower rates than Americans (see HERE). This statement always makes me upset because people take it as a given without really looking into the figures. Cancer supersedes all other causes of death in Japan, period. It is ridiculous to claim that they have lower rates than Americans. What can you eat which will reduce your risk of cancer? A wide variety of minerals and vitamins, with the fat that allows you to absorb them, coming from a variety of foods including properly raised animal foods. See a complete list of nutrients and their sources HERE.
To read more about cardiovascular health and traditional diets see my following posts:
Linking up to Fat Tuesday!