Heart disease is the leading cause of death for both men and women in the U.S. It’s undeniably an important topic of health discussion and research, with leaders such as the USDA making the following recommendations for dietary interventions:
- Avoid high-cholesterol foods
- Choose low-fat or no-fat animal products
- Replace butter and lard with plant-based oils such as margarine
Dietitians and medical professionals have been offering these recommendations to hospital and long-term care patients again and again for years. However, recent scientific research has found that this advice may be misguided.
We know that heart disease is the number one cause of death in Americans, however, the correlation between cholesterol and heart disease is unclear. Based on the study above, having high cholesterol above the age of 60 years old does not directly correlate with developing heart disease. In the study, those with high low-density lipoprotein (LDL), previously termed the “bad” cholesterol, lived as long and longer than those with low LDL.
Additional research is showing that a major cause of heart disease is likely to be inflammation rather than blood lipid levels. Inflammation is the body’s response to injury or infection. Without inflammation, cholesterol is left to circulate freely, and unobstructed. While inflammation can have several causes, diet plays a large role.
Understanding Polyunsaturated Fatty Acids (PUFAs)
One of the main dietary culprits behind inflammation is the imbalanced intake of omega-3 and omega-6 polyunsaturated fats (PUFAs).
Both omega-3 (also referred to as n-3) and omega-6 (n-6) PUFAs compete for the same conversion enzymes within your body in order to be metabolized. This means that an excess of one results in less conversion of the other. Omega-6 fatty acids are pro-inflammatory, while omega-3 fatty acids are neutral. An increase in omega-6 fatty acids leads to higher levels of inflammation, while an increase in omega-3 fatty acids leads to a decrease in inflammation due to decreased conversion of omega-6s.
Balancing Omega-6 and Omega-3
Most fats we eat contain both omega-6 and omega-3 fatty acids, though the ratio varies from food to food.
Your prehistoric ancestors ate in a way which provided their overall PUFA intake mostly in a balanced ratio of 1:1. The main source of dietary fat during this time was seafood, which contains almost exclusively omega-3 fatty acids. Omega-6—rich foods, primarily nuts and seeds, were consumed in very small quantities due to the limitations of manually harvesting, peeling, and eating these foods.
Today’s dietary guidelines are somewhat more permissive, with a recommended ratio of omega-6 to omega-3 being anywhere from 2:1 to 4:1. However, the Center of Genetics, Nutrition, and Health reports that the average American eats a PUFA ratio near 15:1—about five times the recommended ratio.
Omega-6 Fatty Acids on the Rise
Two main factors led to the modern-day overconsumption of omega-6s:
- The development of large-scale factory farms. Under this model, animals are fed primarily with n-6-rich cereal grains, rather than grass.
- Industrialization of seed and nut pressing, which led to large-scale production of cheap food-grade oils that are high in omega-6.
Of these two, industrialized oil production is the leading cause of increased n-6 consumption.
In 2007, the USDA published a report observing the following food trends from 1909-2004:
- Overall total fat intake rose by about 49%.
- Surprisingly, fat contribution from red meat actually decreased from one-third of all fat intake to only about one-sixth in 2004.
- Daily cholesterol intake, per person, decreased from an average of 440 mg per person, per day, to 430 mg daily.
These numbers indicate that Americans have largely replaced animal fats with other fat sources—namely processed oils derived from grain and seeds.
Industrialization of Vegetable Oils
Industrialized oils with a highly unfavorable omega-6 content include those derived from:
These oils are typically given a standard label of “vegetable oil.”
While many households have moved away from cooking with these inflammatory oils, the commercial food supply is rife them:
- Restaurant food: Since it is cost-effective, many fast food or casual dining restaurants prepare food using soybean or vegetable oil.
- Factory-farmed meats: Animals on factory farms are fed diets rich in cereal grains that can include n-6. They then accumulate the n-6 fatty acid in their tissues.
- Pre-packaged foods: Most pre-packaged foods are prepared with high levels of n-6 oils, including many salad dressings.
5 Steps to Balance Your Polyunsaturated Fat Ratio
While you may not be able to fully avoid these oils, here are five easy steps to modify your intake of polyunsaturated fats to a more favorable ratio.
1. Avoid the Oil—Eat the Whole Food
Instead of risking the inflammatory effects of industrialized oils, aim to get these fats out of the whole foods themselves as much as possible. Studies have shown that a diet that includes whole nuts and seeds is linked with a lower risk of heart disease and inflammation.
2. Cook at Home
It’s common for fast food and casual dining atmospheres to cook with soybean or vegetable oil because they are cheap options. Unfortunately, they are also some of the most inflammatory oils around. Cook at home, where you can control the amount of oil you add. When you do need to use oil, choose an option with a more balanced profile such as:
3. Choose Grass-Fed Animal Products
If you choose to eat meat, choose animals who have grazed and fed on grass for most of their lives. This also applies to eggs. According to a study conducted by Penn State, eggs from chickens allowed to graze in pastures had more than two times the amount of omega-3 fatty acids than their caged counterparts, which ate a low-quality, commercial diet.
4. Eat Fish Twice Weekly
Fish do not innately contain n-3 fatty acids; they accumulate it from the algae and plankton on which they feed. The American Heart Association recommends two, 3.5-ounce servings of fatty fish weekly to achieve optimal omega-3 intake.
Fatty fish options include:
- Lake Trout
Note: Avoid eating high-mercury containing fish, especially if under the age of 12 or pregnant. This includes:
- King Mackerel
These age groups may safely consume up to 12 ounces weekly of other, low-mercury fish.
5. Consider Omega-3 Supplementation
If twice-weekly seafood consumption is not realistic for you, consider a high-quality omega-3 supplement. Individuals should not exceed 3 grams per day without a physician monitoring, as high intakes may cause excess bleeding. Talk to your doctor about a dose that is right for you.
In regards to added fats, the rapidly changing food supply has confused consumers and medical professionals alike. Despite previous misconceptions, emerging research is clear. By mindfully consuming processed oils and focusing on fish or omega-3 supplementation, you can eat in a way that improves inflammation, ultimately decreasing your risk of cardiovascular disease.
*Editor’s Note: The information in this article is intended for your educational use only; does not necessarily reflect the opinions of the Chopra Center's Mind-Body Medical Group; and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health providers with any questions you may have regarding a medical condition and before undertaking any diet, supplement, fitness, or other health program.