Higher salt intake associated with increased risk for type 2 diabetes

Key takeaways:

• This is the first study to show that managing salt intake can prevent type 2 diabetes, an expert said.
• The association was mediated by BMI, waist to hip ratio and C-reactive protein.

Greater salt consumption was linked to an increased risk for type 2 diabetes, according to a study published in Mayo Clinic Proceedings.

“We already know that limiting salt can reduce the risk for cardiovascular diseases and hypertension, but this study shows for the first time that taking the saltshaker off the table can help prevent type 2 diabetes as well,” Lu Qi, MD, PhD, a professor at the Tulane University School of Public Health and Tropical Medicine, said in a press release.

For their study, Qi and colleagues evaluated 402,982 participants aged 37 to 73 years from the U.K. Biobank. The cohort was given a questionnaire at baseline asking how often they added salt to foods, with the options being “never or rarely,” “sometimes,” “usually” and “always.”

Overall, there were 13,120 incidents of type 2 diabetes documented over a median follow-up of 11.9 years.

Compared with those who never or rarely added salt to food, the adjusted HRs were:

• 1.11 (95% CI, 1.06-1.15) for those who sometimes added salt;
• 1.18 (95% CI, 1.12-1.24) for those who usually added salt; and
• 1.28 (95% CI, 1.2-1.37) for those who always added salt.

Qi and colleagues did not find any significant links between salt frequency and hypertension or other risk factors for type 2 diabetes.

However, BMI, waist to hip ratio and C-reactive protein mediated the observed association by 33.8% (95% CI, 24.6-43), 39.9% (95% CI, 29.1-50.8) and 8.6% (95% CI, 5.6-11.5), respectively.

The mediated effect from BMI was driven by body fat mass rather than body fat-free mass, the researchers wrote.

They added that there were several limitations to the study. For example, they could not rule out that high frequencies of salt intake are possible markers of an unhealthy lifestyle, and self-reports of salt frequency may have been vulnerable to bias.

Qi said in the release that future research is still needed to determine causations behind the association, but salt consumption may lead people to eat larger portions of food, thus increasing the risk for factors like inflammation and obesity.

Ultimately, switching to low-sodium seasoning is “not a difficult change to make, but it could have a tremendous impact on your health,” Qi said.

References:

• New research links high salt consumption to risk of type 2 diabetes. https://news.tulane.edu/pr/new-research-links-high-salt-consumption-risk-type-2-diabetes. Published Nov. 1, 2023. Accessed Nov. 6, 2023.
• Wang X, et al. Mayo Clin Proc. 2023;doi:10.1016/j.mayocp.2023.02.029.