HMRI nutrition researchers at the University of Newcastle (UON) have found evidence that women and men respond differently to omega-3 fats when used as preventative measures for type 2 diabetes. Now, the researchers want to know why.

PhD candidate Kylie Abbott from the Nutraceuticals Research Program is recruiting for a clinical trial called O3FA-IR. She will examine ‘sexual dimorphism’ in the effect of omega-3 fats on insulin resistance.

“We found in a cross-sectional study that type 2 diabetes was inversely associated with omega-3 status in females, but not males,” Ms Abbott explained. “In other words, omega-3s seem to improve levels of insulin resistance in women only, which might be because they’re better able to metabolise them.”

Ms Abbott said type 2 diabetes occurs when the body’s own insulin level is unable to overcome insulin resistance, which is often a consequence of obesity. This causes sugars to remain in the blood stream rather than transfer to cells and tissues.

“By targeting insulin resistance we might be able to prevent type 2 diabetes from developing in the first place” Ms Abbott added. “But we also need to have a better understanding of the differences between men and women, so that we can target our nutrition interventions to where they are going to have the greatest effect.”

Researchers say that fat distribution differs between the genders, while sex hormones also affect diabetes risk differently – for example, testosterone protects males whereas it predisposes women to diabetes.

Because of the resulting confusion, some health professionals are hesitating to recommend fish oil tablets with omega-3 fats for type 2 diabetes prevention.

“We want to eliminate any doubts arising from the literature and also design strategies to change dietary guidelines,” Ms Abbott said. “Our trial aims to determine how omega-3 fats and sexual hormones interact so we can work out why the two genders respond differently.

“While we continue to make efforts to reduce body weight to combat chronic disease, we are also hoping to create a more metabolically healthy obese phenotype, where people may be overweight but still not at risk of developing metabolic disease such as type 2 diabetes.”

To be eligible for the O3FA-IR trial, participants must be aged 18-70 with a Body Mass Index (BMI) of 25-45kg/m2 and no previous diagnosis of diabetes. Those currently taking fish oil supplements or eating more than two serves of oily fish per week are not eligible.

Email kylie.abbott@uon.edu.au or phone 4921 5638.

News article courtesy of HMRI