Widespread omega-3 deficiency harms health

Omega-3 fatty acids, which we primarily get from oily fish, play a crucial role in brain function and numerous metabolic processes. However, deficiencies have become a global issue, while many people simultaneously consume excessive amounts of omega-6 fatty acids from vegetable oils and industrially processed foods. A review article in AJPM Focus reveals that this imbalance increases the risk of a wide range of diseases linked to chronic inflammation - including cardiovascular disease, cancer, arthritis, PMS, fatty liver, depression, other neurological disorders, and premature birth. The researchers emphasize the need to restore the historical balance by reducing omega-6 intake and increasing omega-3 consumption. This could help prevent and treat many serious conditions more effectively.

Omega-3 and omega-6 fatty acids are embedded in cell membranes, where they regulate a variety of metabolic functions. Omega-3s are particularly vital for the brain, nervous system, and eyes. There should be a balance between these two types of fatty acids to support normal metabolic activity.
However, 86 percent of the global population does not get enough dietary omega-3. Throughout history, oily fish have been the primary and most effective source of omega-3s, as they contain the biologically active forms EPA and DHA, which are also found in cell membranes. Plant-based sources such as flaxseed oil, walnuts, and rapeseed oil also contain omega-3s, but in the form of ALA, which many people struggle to convert into EPA and DHA.
Meanwhile, omega-6 intake has increased dramatically due to the widespread use of inexpensive vegetable oils, margarine, salad dressings, processed spreads, French fries, chips, ready-made meals, and other industrially processed foods.
Animal feed and farmed fish diets are also often rich in omega-6, which affects the final food products.
As a result, the omega-3 to omega-6 ratio in the modern diet is often 1:20, whereas historically it was closer to 1:4. This imbalance contributes to a significantly higher risk of numerous chronic inflammation-related diseases.
Researchers from Case Western Reserve University in Ohio, USA, have explored this issue in depth. According to their recent review, widespread omega-3 deficiency is associated with an increased risk of reduced quality of life and the following conditions:

• Cognitive decline and dementia
• Depression and anxiety
• Cardiovascular disease
• Breathing difficulties
• PMS and menstrual pain
• Joint pain and arthritis
• Various cancers (breast/prostate/colon)
• Non-alcoholic fatty liver disease
• Premature birth

There is also evidence suggesting that adequate omega-3 intake through diet may reduce the risk of these conditions. At the same time, many individuals should lower their intake of omega-6 fatty acids.

Practical recommendations

As mentioned, oily fish is the best dietary source of omega-3 fatty acids because it provides the biologically active forms EPA and DHA. However, the review highlights the issue of fish contamination with heavy metals and other environmental toxins. Therefore, it is recommended to prioritize fish lower on the food chain - such as herring, anchovies, mackerel, and wild salmon - and avoid predatory fish like tuna and halibut, as well as whale meat.
In general, it is advised to consume 350 grams of fish per week, most of which should be oily fish. For heart health, a daily intake of 250 mg of combined EPA and DHA is recommended. In the context of preventing and managing chronic inflammation, higher daily doses are often necessary -especially of EPA - with several researchers recommending 900 - 1,200 mg per day.
For those who dislike fish or consume too little, supplements can be a good alternative, provided they are documented for purity and quality. The product label should clearly state the amount of EPA and DHA per capsule or daily dose.

References

Timothy H Ciesielski. Global Access to Uncontaminated Omega-3 Polyunsaturated Fatty Acids Requires Attention. AJPM Focus. 2025

Case Western Reserve University. Global shortage of essential nutrient poses health concern. ScienceDaily 2025

Anne-Marie Chalmers. How Much Omega-3 Per Day Should I Take? Omega-3 Innovations. 2020