Sea Food Linked to Healthier Kidneys

Diabetes and hypertension are two of the most common causes of renal pathology. Infection, particularly ascending infection, becomes more common as one gets older, as immune function weakens and concomitant diseases conducive to infection, such as obstructive uropathy, become more prevalent. The majority of pathological alterations in the kidney appear to be caused by oxidative stress, which is then followed by an inflammatory response. The imbalance between free radicals and their elimination by endogenous and external scavengers, including polyunsaturated fatty acids, causes oxidative stress (PUFA). Decades-old research found that PUFA supplementation delayed the rate of renal function loss in patients with IgA nephropathy. Studies on omega-3 supplementation in dialysis patients show that it has a positive effect on triglyceride levels (2^✔ ✔Trusted Source
Omega-3 and renal function in older adults

).

Recent studies have examined the strength of the relationship between omega-3 fatty acids present in seafood and kidney function. Although the relationship was small, the researchers say the findings confirm current clinical guidelines that encourage adequate consumption of seafood and fatty fish as part of healthy dietary patterns.

Chronic kidney disease (CKD) affects over 700 million individuals globally and can lead to renal failure and death; therefore, variables that may prevent its onset and progression must be identified.

Animal studies suggest that omega-3 polyunsaturated fatty acids (n-3 PUFAs) may be advantageous to kidney function; however, human research is sparse and depends primarily on dietary questionnaires, which can be inaccurate.

To investigate further, an international team led by researchers from The George Institute for Global Health and the University of New South Wales pooled the findings of 19 studies from 12 countries that looked at the links between n-3 PUFA biomarkers and the development of CKD in adults up to May 2020.

Eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), docosapentaenoic acid (DPA), and alpha-linolenic acid were among the biomarkers studied (ALA). The main dietary sources of EPA, DHA, and DPA are seafood, while ALA is mostly found in plants (nuts, seeds, and leafy green vegetables).

A glomerular filtration rate (eGFR) of less than 60 ml/min/1.73 m2 was used to diagnose CKD. eGFR is a measurement of how well the kidneys remove waste and excess fluid from the blood. The standard range is 90-120 ml/min/1.73 m2.

The main analysis includes 25,570 participants in total. Their ages ranged from 49 to 77 years, and their eGFR ranged from 76.1 to 99.8 mL/min/1.73 m2.

Sixteen researchers enrolled both men and women, with the majority of participants being white. During an average of 11 years of follow-up, 4,944 participants (19%) developed CKD.
After controlling for age, gender, race, BMI, smoking, alcohol use, physical activity, heart disease, and diabetes, greater levels of total seafood n-3 PUFAs were related to a moderately (8%) decreased risk of developing CKD.

When individuals were divided into five groups based on their n-3 PUFA levels, those in the highest fifth had a 13% lower risk of CKD than those in the lowest fifth.
Higher amounts of total n-3 PUFAs in seafood, particularly DHA, were similarly linked to a slower annual fall in eGFR. Individuals with the highest total seafood n-3 PUFA level, for example, had a 0.07 mL/min/1.73 m2 lower annual fall in eGFR than those with the lowest total seafood n-3 PUFA level.

Plant-Derived ALA Levels were not Linked to Chronic Kidney Diseases

.

These are observational observations, and the researchers admit that differences in study design and techniques could have influenced their findings. Furthermore, they cannot rule out the possibility that some of the observed risks are the result of unmeasured factors.

Nevertheless, following further examination, the results were similar and were constant across age groups (60 or less vs. more than 60 years), eGFR (60-89 vs. 90 or higher mL/min/1.73 m2), high blood pressure, diabetes, and coronary heart disease at baseline, indicating that they held up to scrutiny.

“Although our findings do not prove a causal relationship between seafood n-3 PUFAs and CKD risk, they are supportive and consistent with current clinical guidelines that recommend adequate intake of seafood as part of healthy dietary patterns, particularly when seafood replaces the intake of less healthy foods,” the researchers write.

Thus, it can be concluded that further randomized controlled trials are warranted to assess the potential beneficial role of seafood n-3 PUFAs in preventing and managing CKD.

References :

1. Association of omega 3 polyunsaturated fatty acids with incident chronic kidney disease: pooled analysis of 19 cohorts – (https://www.bmj.com/content/380/bmj-2022-072909)
2. Omega-3 and renal function in older adults – (https://pubmed.ncbi.nlm.nih.gov/20041816/)

Source: Medindia