Omega-3s are healthy fats that support many important functions in the body. They are classified as essential, meaning the body cannot produce them and must obtain them through the diet. Omega-3s are best known for supporting heart and brain health, but they also play a role in maintaining vision, joint health, and the body’s normal inflammatory response. Omega-3 fats and CKD are also important.
There are three main types of omega-3s: ALA, EPA, and DHA. EPA and DHA are primarily found in seafood and are especially important for brain and heart function. ALA comes from plant foods and can be partially converted by the body into EPA and DHA.
Omega-3 and CKD versus Omega-6
Like omega-3 fatty acids, omega-6 fats are also necessary for good health. However, when consumed in large amounts, omega-6 fats tend to promote inflammatory pathways, whereas omega-3s are associated with anti-inflammatory effects. This does not mean that omega-6s are harmful. Omega-6 fats are essential for initiating the appropriate inflammatory responses needed for immune defence and tissue repair. They are commonly found in vegetable oils, including corn, soybean, sunflower, and safflower oils, as well as in many processed and packaged foods.
In North America, diets are typically high in omega-6 fats and relatively low in omega-3s. This imbalance may contribute to chronic low-grade inflammation in the body. For individuals with chronic kidney disease, inflammation is already a concern, as it is associated with disease progression and increased cardiovascular risk. The ideal ratio of omega-6 to omega-3 consumption is 4:1 but the Western diet provides a 40:1 ratio. As a result, a consistently high intake of omega-6 fats combined with low omega-3 intake may be less supportive of kidney health and overall well-being.
Omega-3 and CKD
Higher levels of omega-3 intake is associated with a lower risk of developing CKD. For those who have already become diagnosed with CKD, omega-3 helps to lower the production of pro-inflammatory molecules and reduce inflammation. CKD patients are also at a higher risk for cardiovascular disease and omega-3 helps to reduce this risk by playing a part in regulating triglyceride (fat) levels, improving blood vessel function, and contributing to blood pressure regulation.
Overall, omega-3s should be highlighted in all diets, especially for those who have CKD. Intake should always be discussed with a healthcare provider, particularly for individuals with advanced CKD or specific dietary restrictions.
Animal-based sources of Omega-3 and CKD
Animal-based foods are the primary sources of the omega-3 fatty acids EPA and DHA, the forms that are most readily used by the body. These omega-3s are absorbed efficiently and do not require conversion, making animal sources especially valuable for meeting omega-3 needs through diet.
Fatty fish are the richest dietary sources of EPA and DHA. Salmon, sardines, mackerel, anchovies, herring, and trout consistently provide high amounts per serving. Shellfish such as oysters, mussels, and crab also contain omega-3s, though typically in smaller quantities. For individuals who eat animal products but not fish, eggs enriched with omega-3s can contribute modest amounts.
When choosing animal-based omega-3 sources, preparation matters. Baking, grilling, or steaming fish and shellfish helps preserve omega-3 content without adding excess saturated fat or sodium. Fried or heavily processed fish products generally provide fewer benefits.
Processed fish products, smoked fish, and canned fish with added salt can be high in sodium, which may contribute to fluid retention and blood pressure concerns. Some seafood also contains higher phosphorus levels, which may be a concern for individuals with reduced kidney function. When choosing omega-3 foods and CKD such as fresh or frozen fish without added ingredients and preparing it using simple cooking methods can help limit excess sodium and additives.
Plant-based Omega-3 foods
Plant-based omega-3s come primarily from alpha-linolenic acid (ALA), a form of omega-3 found in certain seeds, nuts, and plant oils. ALA serves as a building block that the body can partially convert into the longer-chain omega-3s used for various physiological processes. While this conversion is limited, plant-based sources still contribute to overall omega-3 intake, especially for individuals who eat little or no fish.
Common plant-based sources of omega-3s include flaxseeds and flaxseed oil, beans, edamame, avocado, chia seeds, hemp seeds, walnuts, and oils such as canola and soybean oil. Ground flaxseed and chia seeds are particularly versatile and can be added to foods like oatmeal, yogurt, or baked goods. Walnuts provide omega-3s along with healthy fats and can be used as snacks or incorporated into meals.
When considering plant-based omega-3 foods and CKD, portion sizes and mineral content should be considered when adding plant-based sources of omega-3 into one’s diet just like when including animal-based sources. This is as some foods contain potassium or phosphorus.
Omega-3 and CKD
Including omega-3 foods and CKD may help to minimize inflammation and support heart health with CKD. Working with a dietitian who supports those with kidney disease can help you plan a balanced diet.
This article was written by Kimia Oshagi, Nutrition Student Volunteer.
This article was reviewed by Emily Campbell, RD CDE MScFN.
