The longitudinal study published in The American Journal of Clinical Nutrition evaluated participants over 24 years and found a potential sex difference for the beneficial effects, highlighting a need for further research.
The findings suggested that linoleic acid (LA) and alpha-linolenic acid (ALA) positively affected markers of cardiometabolic health, including BMI, cholesterol, blood pressure and triglycerides.
“Our findings further support the current guidelines in adults recommending the intake of plant-based fats such as rapeseed and sunflower oil, rich in LA and ALA,” wrote researchers at the Institute of Environmental Medicine in Stockholm and other institutions in Sweden.
PUFAs and weight management
PUFAs are mostly consumed as plant-based fats in vegetable oils and nuts. Although scientists do not know the exact mechanism by which PUFAs may reduce obesity, they believe they may induce thermogenesis and fat oxidation.
A recent review of evidence concluded that PUFAs such as ALA and LA may be more effective than marine-based omega-3 fatty acids in modulating body composition, at least in adults.
“PUFAs may also inhibit de novo lipogenesis, as LA has been found to reduce lipogenic markers, which in turn were closely associated with an LA-induced reduction of liver fat content,” the current study noted.
Study details
Researchers included 688 participants from the prospective birth cohort Barn Allergi Miljö Stockholm Epidemiologi (BAMSE), which followed 4,089 participants who were born between 1994 and 1996 in Stockholm County, Sweden.
All 688 participants chosen had completed the questionnaire, attended the clinical examination at age 24 and had data about fatty acids in plasma phospholipids at age 8 or 16 years.
The researchers used this data, along with recorded measurements of body mass index (BMI), waist circumference, fat mass and blood pressure to evaluate associations between PUFAs and cardiometabolic health outcomes.
The results revealed that in females, LA and ALA at 16 years were inversely associated with BMI and obesity markers at 24 years.
Also in females, higher plasma proportions of LA were associated with lower blood pressure, triglycerides, LDL-cholesterol and total cholesterol. ALA at 16 years was associated with lower LDL cholesterol at 24 years.
“Indeed, females with plasma proportions of LA above the median both at 8 (21.36%) and 16 y (21.86%) had nearly 50% lower odds of being overweight or obese at 24 y compared with those with LA proportions below the median [OR: 0.58 (0.35, 0.97) and OR: 0.54 (0.32, 0.90), respectively,” the researchers wrote.
They found no associations between long-chain omega-3 fatty acids or arachidonic acid (AA) for any of the outcomes they studied. Also, they observed no significant associations in males.
Commenting on the sex differences, the researchers noted that their study included more females, giving them higher statistical power and that there may be “different susceptibility among males and females across the life course.”
Noting the benefits of the population-based longitudinal design of the study, the researchers also acknowledge that plasma proportions of PUFAs can reflect short-term dietary changes and could misclassify some participants’ long-term diets, suggesting a need for further studies.
Source: The American Journal of Clinical Nutrition. doi: 10.1016/j.ajcnut.2024.11.029. “Biomarkers of dietary PUFA intake in childhood and adolescence in relation to cardiometabolic risk factors in young adulthood: a prospective cohort study in Sweden”. Authors: A.M. Igra et al.