Scientists Uncover Surprising Benefits of Omega-6
By Fatty Acid Research Institute
Public concern over seed oils has been growing, largely
because many of these oils are rich in linoleic acid (LA), an
essential omega-6 fatty acid. Critics argue that Western diets are overloaded
with LA, suggesting this shift is a key contributor to many modern health
issues.
According to this view, elevated levels of LA are believed
to drive chronic inflammation. But is there solid evidence that consuming more
LA — and having higher levels of it in the bloodstream — actually leads to
increased inflammation?
Investigators relied on data from the Framingham Offspring Study, a well-known research cohort from the Boston area. The Framingham Offspring Study is a landmark longitudinal research initiative that follows the children of participants in the original Framingham Heart Study to investigate genetic and lifestyle factors influencing cardiovascular and metabolic health.
Launched in 1971, it has provided decades of valuable insights into chronic
disease risk and prevention. The cohort’s rigor and continuity make it one of
the most trusted sources for understanding long-term health trajectories.
Study Design and Biomarker Analysis
This was a cross-sectional study, meaning that the LA and
arachidonic acid (AA) levels were measured in the same blood samples as the 10
inflammation-related biomarkers in 2700 individuals. The relationships between
the levels of these two omega-6 fatty acids and 10 separate blood/urine
biomarkers of inflammation and oxidative stress were statistically evaluated.
After adjusting (controlling statistically) for multiple
other potentially confounding factors (age, race, sex, smoking, blood lipid
levels, blood pressure, body weight, etc.), the researchers found that higher
LA levels were associated with statistically significantly lower levels
of five of the 10 biomarkers, and in no case was higher LA related to higher
levels of any biomarker. For AA, higher levels were linked with lower
concentrations of four markers, and, like LA, there were no statistically
significant associations with higher levels of inflammation/oxidation.
Implications for Dietary Recommendations
“These new data show clearly that people who have the
highest levels of LA (and AA) in their blood are in a less inflammatory state
than people with lower levels. This finding is exactly the opposite of what one
would expect if omega-6 fatty acids were ‘proinflammatory’ – in fact, they
appear to be anti-inflammatory,” explained study investigator William S.
Harris, PhD; President Fatty Acid Research Institute; Founder, OmegaQuant
Analytics, LLC; and Professor, Department of Internal Medicine, Sanford School
of Medicine, University of South Dakota, Sioux Falls, SD.
“In the flurry of news stories about the harms of seed oils – the primary sources of LA in the diet – many voices are calling for reducing Americans’ intakes of LA. This is not a science-based recommendation, and this study – in addition to many more – point in precisely the opposite direction: instead of lowering LA intakes, raising intakes appears to be a healthier recommendation,” Dr. Harris continued.
“These findings contradict a narrative,
not previous research findings. There are many studies in the medical
literature that are consistent with our findings here.”
Reference: “Red Blood Cell Omega-6 Fatty Acids and
Biomarkers of Inflammation in the Framingham Offspring Study” by Heidi T. M.
Lai, Nathan A. Ryder, Nathan L. Tintle, Kristina H. Jackson, Penny M.
Kris-Etherton and William S. Harris, 21 June 2025, Nutrients.
DOI: 10.3390/nu17132076
