An excess of red meat might harm kidneys, study suggests
In the survey carried out on 63,257 Chinese adults, scientists strongly associated red meat intake with an increased risk of end-stage renal disease (ESRD).
Subjects eating the highest amounts of red meat had a 40% increased risk of developing ESRD compared with people consuming the lowest amounts.
Replacing one serving of red meat with alternative sources of protein lowered the risk by up to 62%.
The findings are in keeping with other observations about diets heavy in red meat. One US study found that women with higher intake of red and processed meats had a higher risk of decline in kidney function.
A dietary pattern of largely processed and fried foods has also been linked with an increased risk of mortality in patients with chronic kidney disease (CKD).
Study partnership
The collaboration between Duke-NUS Medical School and the National University of Singapore saw the team assess data collected from 63,257 adults that made up the Singapore Chinese Health Study cohort group.
This population proved suitable as 97% of red meat intake consisted of pork.
Poultry, fish and shellfish, eggs, dairy products, soy and legumes are also good sources of protein.
These subjects, aged 45–74 years were asked about their dietary habits from 1993 to 1998. A follow-up after 15.5 years recorded 951 cases of ESRD.
Red meat intake was strongly associated with ESRD risk in a dose-dependent manner with individuals in the top 25% of red meat consumption having a 40% increased risk of developing ESRD vs. the lowest 25% of meat consumption.
Further analysis revealed that replacing one serving of red meat with other food sources of protein associated with a maximum relative risk reduction of 62.4%. Finally, intake of poultry, fish, eggs or dairy products did not associate with risk of ESRD.
No firm conclusions
Although the health implications of red meat consumption have been discussed, firm conclusions have been hard to come by.
The decreased risk of CKD incidence or progression and death with a healthier dietary pattern was also observed.
Subjects who consumed a high intake of healthy foods such as vegetables and lower intake of unhealthy foods such as fried foods had lower risks of developing CKD.
However, they also found a higher intake of meat decreased CKD incidence or progression, which contrasts with the results of this latest study.
The team pointed to red meat’s ability to produce more acid that other protein-rich foods, and could explain the observed association between red meat and ESRD risk in the study population.
Other explanations include the roles of nitrites, nitrates, heme iron, advanced glycation endproducts (AGEs) and advanced lipoxidation endproducts (ALEs) found in red meat.
"We embarked on our study to see what advice should be given to CKD patients or to the general population worried about their kidney health regarding types or sources of protein intake," said Woon-Puay Koh, study author from the Duke-NUS Medical School.
"Our findings suggest that these individuals can still maintain protein intake but consider switching to plant-based sources; however, if they still choose to eat meat, fish/shellfish and poultry are better alternatives to red meat."
Source: Journal of the American Society of Nephrology
Published online ahead of print, doi: 10.1681/ASN.2016030248
“Red Meat Intake and Risk of ESRD.”
Authors: Woon-Puay Koh et al.
