Polyunsaturated fats are essential fatty acids. The human body needs them for many functions, from building healthy cells to maintaining brain and nerve function. Our bodies can’t produce them, therefore our only source is food. These polyunsaturated fats are important, as they help lower the risk of heart disease. Some studies suggest these fats may also protect against type 2 diabetes, Alzheimer’s disease, depression and age-related brain decline.
Polyunsaturated fats are broken up into sub-categories. The two discussed in this article are:
- Omega-3 fatty acids are polyunsaturated fatty acids that are essential nutrients for health. We need omega-3 fatty acids are needed for numerous normal body functions, such as controlling blood clotting and building cell membranes in the brain. Since our bodies cannot produce omega-3 fats, we must obtain them from food.
- Omega-6 fatty acids are also polyunsaturated fatty acids that are essential nutrients, meaning that our bodies cannot produce them, and again we must obtain them from food. They are abundant in the western diet. Common sources include safflower, corn, cotton seed, and soy bean oils.
A healthy diet contains a balance of omega-3 and omega-6 fatty acids. Omega-3 fatty acids help reduce inflammation, and some omega-6 fatty acids tend to promote inflammation. The typical Australian diet tends to contain 10 times more omega-6 fatty acids than omega-3 fatty acids.
It is suggested that human beings evolved on a diet with a ratio of omega-6 to omega-3 essential fatty acids of approximately 1:1. Whereas in western diets, the ratio is up to 15:1. Western diets as a whole, are deficient in omega-3 fatty acids, and have excessive amounts of omega-6 fatty acids. Excessive amounts of omega-6 polyunsaturated fatty acids and a very high omega-6/omega-3 ratio, promote the pathogenesis of many diseases, including cardiovascular disease, cancer, inflammatory and auto-immune diseases, whereas increased levels of omega-3 PUFA exert suppressive effects.
In the secondary prevention of cardiovascular disease, a ratio of 4:1 is associated with a 70% decrease in total mortality. A ratio of 2.5:1 reduced rectal cell proliferation in patients with colorectal cancer, whereas a ratio of 4:1 with the same amount of omega-3 PUFA had no effect. The lower omega-6 to omega-3 ratio in women with breast cancer is associated with decreased risk. A ratio of 2-3:1 suppressed inflammation in patients with rheumatoid arthritis. A ratio of 5:1 had a beneficial effect on patients with asthma, whereas a ratio of 10:1 had adverse consequences. A lower ratio of omega-6 to omega-3 fatty acids is more desirable in reducing the risk of many of the chronic diseases of high prevalence in western societies.
Here are some tips to help adjust your omega-6 to omega 3 ratio to become closer to 4:1.
Avoid using oils high in omega- 6 fatty acids, such as sunflower oil, corn oil, and soy bean oil. Olive oil is the perfect alternative, with only 9% omega 6 fatty acids.
Eat animal based foods that are higher in omega-3 fatty acids, such as pasture fed beef, lamb, chicken (including pastured eggs) and oily fish.