When we cook, vegetable oils often factor into the equation—sautéed, fried, and other cooking methods often require their use. Yes, they add flavor and ease of cooking to our foods, but are vegetable oils good for us?
Linoleic Acid–‘Friend’ or ‘Foe?’
Some would consider linoleic acid to be a “friend” to our health—a superhero who fights heart disease, raises good cholesterol levels, and helps control blood sugar—a view based on scientific studies. Here are a few examples:- A meta-analysis published in 2019 in the journal Circulation showed that higher circulating and tissue levels of linoleic acid were associated with a lower risk of major cardiovascular issues. These results support the positive role of linoleic acid in cardiovascular disease prevention.
- A 2019 article by Harvard Health Publishing, a division of Harvard Medical School, pointed out that omega-6 fats extracted from vegetable oils are beneficial, reducing harmful LDL cholesterol and raising protective HDL cholesterol. It can also help control blood sugar by increasing the body’s sensitivity to insulin.
- A review study in 2016 pointed out that linoleic acid can have both anti-cancer and cancer-promoting processes. High doses of linoleic acid inhibited the proliferation of colon cancer cell type Caco-2, while high intake of linoleic acid was also shown to offer protection against cancer proliferation.
- Omega-6 has also been shown to promote the in vitro proliferation of breast cancer cell type BT-474 and human lung cancer cell type A549 and can promote the occurrence and growth of colon and prostate tumors in animal models.
Omega-6 to Omega-3 Ratio Is Critical
Fatty acids are divided into “saturated” fatty acids and “unsaturated” fatty acids. Most animal fats are saturated, while most of the fats from plant sources are unsaturated. Both omega-6 and omega-3 contain essential fatty acids that can only be obtained from food, such as linoleic acid (LA), an omega-6 fatty acid, and alpha-linolenic acid (ALA), an omega-3 fatty acid.In modern-day diets, there is a tendency to consume an excess of omega-6 fatty acids while not obtaining enough omega-3 fatty acids. This imbalance in the omega-6 to omega-3 ratio can have negative health implications.
One such mechanism involves the production of eicosanoids derived from arachidonic acid, an omega-6 fatty acid. Eicosanoids have pro-inflammatory properties and can promote adipose tissue growth, insulin resistance, and increased fat storage, all of which can contribute to obesity development.
However, increasing the intake of omega-3 fatty acids, specifically eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), can help rebalance the omega-6 to omega-3 ratio and counteract the negative effects of obesity.
What Oils Are Best for Optimum Health?
Blood tests can detect the ratio of omega-6 to omega-3 in our blood. The ideal ratio of omega-6:omega-3 is 1: 1 to 4:1. If yours exceeds this level, you may need to consider adjusting your diet to balance the ratio.Cooking oils such as soybean, corn, sunflower, peanut, sesame, cottonseed, and rice bran oil are all high in omega-6 fatty acids.
For healthier cooking options select well-sourced, high-quality oils, rich with omega-3 content, such as olive and avocado.
Fast foods and processed foods including granola bars, corn and potato chips, and condiments such as mayonnaise are all high in omega-6 and should be avoided.
Instead, choose foods rich in omega-3 fatty acids such as salmon, mackerel, flaxseeds, avocados, and walnuts to adjust the ratio of omega-6:omega-3 in the body.