Eating at least two portions of oily fish such as sardines or herrings a week is linked to a lower risk of chronic kidney disease and a slower decline in the organ’s function.
Chronic kidney disease affects about 700 million people worldwide. It can lead to kidney failure and death, so there is an urgent need to identify factors that could prevent its onset and progression.
Study has found an association between higher levels of omega 3 fatty acids found in oily fish and other seafood, and a reduced risk of kidney problems. The link was not found with higher levels of plant derived omega 3 fatty acids.
The findings of the international team of researchers, which was led by the George Institute for Global Health and the University of New South Wales, were published in the medical journal the BMJ.
Studies in animals have previously suggested omega 3 fatty acids may help with kidney function, but until now evidence from human research was limited and relied mostly on dietary questionnaires.
The researchers pooled the results of 19 studies from 12 countries examining links between levels of omega 3 fatty acids and the development of chronic kidney disease in adults.
About 25,000 people were included in the main analysis, aged between 49 and 77.
After accounting for a range of factors including age, sex, race, body mass index, smoking, alcohol intake, physical activity, heart disease and diabetes, higher levels of seafood omega 3 fatty acids were associated with an 8% lower risk of developing chronic kidney disease.
When participants were split by levels of seafood omega 3 fatty acids consumed, those in the highest fifth had a 13% lower risk of chronic kidney disease compared with those in the lowest fifth. Higher levels were also associated with a slower annual decline in kidney function.
Nevertheless, results were similar after further analysis, and appeared consistent across age groups.