Omega-6 fatty acids: function, risks & food sources
Omega-6 fatty acids are essential nutrients that our bodies cannot produce on their own.
They must therefore be obtained through the diet. These fatty acids play an important role in many bodily functions, such as maintaining healthy cells and supporting inflammatory responses. Omega-6 and omega-3 fatty acids should be consumed in a balanced ratio. However, in the Western diet, omega-6 is often consumed in significantly higher amounts than omega-3, which can lead to health problems. In this article, you will learn why omega-6 is important, which foods contain it, and what risks are associated with excessive omega-6 intake. High levels of inflammation in the body can be associated with high omega-6 consumption.
Table of Contents
- What are omega-6 fatty acids?
- What functions do omega-6 fatty acids have?
- Are omega-6 fatty acids harmful or healthy?
- How are omega-6 and omega-3 related?
- How do I know if my omega-6 levels are too high?
- How much omega-6 do I need per day?
- Which foods contain omega-6 fatty acids?
- Summary
What are omega-6 fatty acids?
Omega-6 fatty acids belong to the family of polyunsaturated fatty acids and must be obtained from the diet. The omega-6 fatty acids include:
- Linoleic acid (LA): A basic omega-6 fatty acid found in many vegetable oils and serves as a precursor for other omega-6 fatty acids (Fritsche, 2014).
- Arachidonic acid (ARA): Derived from linoleic acid and plays a key role in inflammatory processes (pro-inflammatory) as well as in the function of the brain and nervous system.
- Conjugated linoleic acid (CLA): Structurally different from linoleic acid and found in meat and dairy products.
- Gamma-linolenic acid (GLA): Formed in the body from linoleic acid and found in certain plant oils; it has anti-inflammatory effects (Innes & Calder, 2018).
Source: MedlinePlus, 2022
What functions do omega-6 fatty acids have?
Omega-6 fatty acids are not just simple components of our diet – they fulfill essential functions in our bodies. These include:
- Cell function: Structure and functioning of cells
- Energy production: Provides energy and supports metabolism
- Regulates inflammation: Promotes and regulates inflammatory responses
- Neurological health: Development and function of the brain and nervous system
- Skin and hair health: Promotes healthy skin appearance and strengthens hair structure
Sources: Simopoulus & DiNicolantonio, 2016; Durijic & Calder, 2021
In addition to many important functions of omega-6, the regulation of inflammatory processes is particularly significant: In the human body, omega-6 fatty acids—especially arachidonic acid—play a crucial role in triggering and regulating inflammatory responses. They help the body respond to injury and infection. Inflammatory responses are essential for immune defense and wound healing. In this sense, omega-6 fatty acids—and particularly arachidonic acid—significantly contribute to maintaining the body’s defense mechanisms (Innes & Calder, 2018).
Are omega-6 fatty acids harmful or healthy?
Although omega-6 fatty acids can promote inflammation, they are essential for the body’s immune response and wound healing. Certain types, such as gamma-linolenic acid (GLA), actually have anti-inflammatory effects—similar to omega-3 fatty acids, which are generally considered anti-inflammatory. There is preliminary evidence that gamma-linolenic acid (GLA), a form of omega-6, may help lower high blood pressure. However, more research is needed to understand and confirm the exact role of omega-6 in these processes (Hartley et al., 2015).
Due to their pro-inflammatory properties, excessive intake of omega-6 fatty acids—particularly in relation to omega-3 intake—can contribute to chronic, low-grade inflammation, which may increase oxidative stress in the body. This imbalance is also considered a risk factor for various chronic diseases, such as cardiovascular diseases (e.g., atherosclerosis), autoimmune disorders, asthma, and allergies.
Additionally, studies on the effects of omega-6 fatty acids on blood lipids, such as cholesterol levels, have yielded mixed results. Further research is necessary to better understand the mechanisms of action of omega-6. However, it is clear that a balanced ratio between omega-6 and omega-3 fatty acids is crucial in order to fully benefit from the health-promoting properties of both types of fats.
Sources: Durijic & Calder, 2021; Delgado et al., 2017; Hooper et al., 2018
How are omega-6 and omega-3 related?
The following table highlights the main differences between these two essential nutrients:
| Characteristic | Omega-6 fatty acids | Omega-3 fatty acids |
|---|---|---|
| Major types | Linoleic acid (LA), Arachidonic acid (ARA), Gamma-linolenic acid (GLA) | Alpha-linolenic acid (ALA), Eicosapentaenoic acid (EPA), Docosahexaenoic acid (DHA) |
| Main sources | Vegetable oils such as sunflower oil, corn oil | Fatty fish such as salmon, mackerel |
| Physiological effects | Promotes inflammation, blood clotting, and blood vessel constriction | Inhibits inflammation and blood clotting, dilates blood vessels |
Source: Simopoulus & DiNicolantonio, 2016
For a healthy diet, it is important that the ratio of omega-6 to omega-3 fatty acids lies between 2:1 and 4:1. This helps maintain a healthy balance between pro-inflammatory and anti-inflammatory effects in the body. A balanced intake of these fatty acids can help minimize chronic inflammation and support overall health (DiNicolantonio, 2021).
How do I know if my omega-6 levels are too high?
To check the omega-6 levels in your body, a blood test can be performed. Typically, the concentration of omega-6 fatty acids in red blood cells is measured. These tests are useful for identifying an imbalance in fatty acid levels and for making adjustments to dietary habits if necessary.
How much omega-6 do I need per day?
The daily requirement for omega-6 fatty acids depends on age, sex, and lifestyle. In general, it is recommended that 5–10% of total daily calories come from omega-6. For children, the requirement is about 7g, for male adolescents 16g, female adolescents 11g, adult men 17g, adult women 12g, and for pregnant or breastfeeding women up to 13g (Simopoulus & DiNicolantonio, 2016).
Which foods contain omega-6 fatty acids?
Foods that contain omega-6 fatty acids mainly come from vegetable oils, nuts, seeds, and processed foods. It is advisable to limit the intake of foods with a high omega-6 to omega-3 ratio and to increase the consumption of foods with a more balanced ratio in order to maintain a healthy balance of these essential fatty acids. The omega-6 to omega-3 ratio should not exceed 5:1. The typical Western diet tends to be unbalanced, often resulting in a high intake of omega-6 compared to omega-3 fatty acids, which can increase the risk of health problems (DiNicolantonio & O´Keefe, 2018).
Foods with a favorable omega-6 to omega-3 ratio:
- Chia seeds, hemp seeds, flaxseeds
- Walnuts
- Wild-caught fish (e.g., salmon, mackerel)
- Walnut oil, flaxseed oil, canola oil
Foods with an unfavorable omega-6 to omega-3 ratio:
- Many vegetable oils (sunflower oil, corn oil, soybean oil)
- Many processed foods that contain these oils
- Margarine and other butter-like spreads
- Many dressings and sauces, especially those based on vegetable oils
- Many snacks like chips that are fried or roasted in omega-6-rich oils
- Some types of meat, especially from grain-fed animals, such as conventionally raised poultry
Sources: Mayo Clinic, 2023; Gunnars, 2023
Summary
Omega-6 fatty acids are essential nutrients that play a particularly important role in the regulation of inflammatory processes. While some omega-6 fatty acids, such as gamma-linolenic acid, have anti-inflammatory properties, an excess of omega-6 compared to omega-3 can lead to chronic inflammation and related health problems. A balanced ratio of omega-6 to omega-3—ideally between 2:1 and 4:1—is therefore crucial for health. In the Western diet, this ratio is often skewed in favor of omega-6, primarily due to the high consumption of certain vegetable oils and processed foods.
