Groundbreaking research suggests that a common dietary supplement could play a significant role in preventing two of the world's most prevalent chronic diseases. A series of clinical studies indicates that omega-3 fatty acids, primarily found in fish oil, may help modulate the risk of developing type 2 diabetes (T2D) and cardiovascular disease.
The Global Burden of Type 2 Diabetes
In 2021, approximately 529 million people globally were living with diabetes, the majority with type 2. This complex metabolic disease, which develops when the body cannot produce or use insulin effectively, was linked to 1.6 million deaths that same year. T2D significantly elevates the risk of serious conditions like heart disease and stroke, making it a leading cause of disability and mortality worldwide.
Professor May Faraj, a nutrition researcher at the Université de Montréal and scientist at the Institut de recherches cliniques de Montréal (IRCM), has been investigating nutritional strategies to prevent cardiometabolic diseases. Her work has focused on a key protein marker: apolipoprotein B (apoB).
Unravelling the ApoB and Inflammation Link
Historically, high levels of apoB—a protein found in low-density lipoprotein (LDL) or 'bad cholesterol' particles—were considered a consequence of T2D. However, clinical data from Professor Faraj's unit, corroborated by large population studies, shows that high blood apoB is both a cause and a consequence of the disease. The precise mechanisms and potential nutritional interventions remained unclear.
To explore this, Professor Faraj's team conducted a clinical study between 2013 and 2019 involving 40 healthy volunteers not taking medication. The participants took a daily supplement of 2.7 grams of the omega-3 fatty acids EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) for 12 weeks while maintaining their usual diet.
The researchers measured the participants' carbohydrate and fat metabolism, along with inflammatory responses in their adipose (fat) tissue, before and after the supplementation. Chronic inflammation, which persists without infection, is a known driver of diseases like T2D and cardiovascular disease.
Promising Findings from the Clinical Trial
The study yielded significant results, published in the journal Scientific Reports in 2023 and 2024. Before taking omega-3s, subjects with high blood apoB exhibited greater adipose tissue inflammation, which was linked to metabolic abnormalities that raise T2D and cardiovascular risk.
After three months of EPA and DHA supplementation, the ability of the participants' LDL to induce inflammation in their own fat tissue was reduced. Furthermore, the link between this inflammation and numerous T2D and heart disease risk factors was eliminated.
The supplements also improved the body's ability to secrete insulin in response to blood sugar and to clear fat from the blood after a high-fat meal. The research indicated that higher levels of DHA, in particular, were associated with a greater reduction in risk factors.
How to Get Enough Omega-3s
EPA and DHA are essential fats that must be obtained through diet, as the body cannot produce them in sufficient quantities. The Heart and Stroke Foundation of Canada recommends eating two portions of fish per week, especially oily varieties like salmon, mackerel, and herring. This can provide roughly three grams of EPA and DHA weekly.
While plant-based sources like flaxseed contain omega-3s, the human body is inefficient at converting them into EPA and DHA. Therefore, fish oil supplements are a practical alternative. Health Canada states that an intake of up to five grams of EPA and DHA daily can support cardiovascular and cognitive health, reduce blood fats, and ease rheumatoid arthritis pain.
Professor Faraj advises consumers to look for supplements with the Internationally Verified Omega-3 (IVO) certification or similar third-party verification to ensure purity and potency.
These findings propose that targeting individuals with high apoB levels with EPA and DHA supplementation could be a powerful strategy to lower their risk of two debilitating global diseases. Professor Faraj's team is now investigating why lowering LDL cholesterol in some people might increase T2D risk while decreasing cardiovascular risk, and the role omega-3s may play in this paradox.
