In this cohort study based on NHANES data, we analyzed 6887 participants (including 1021 patients with T2DM) and conducted a clinical follow-up over a median duration of 10 years. Our study yielded the following key findings: First off, among those with T2DM, higher MIND diet adherence was substantially linked to a lower risk of death from all causes and CVD. Secondly, the protective effect of the MIND diet on prognosis was also observed in the overall population, but not in the non-DM population. These conclusions remained consistent after performing subgroup and sensitivity analyses.

The MIND diet has showed various protective roles, such as improving cognitive performance [15], enhancing physical function including muscle strength [18], and reducing the risk of breast cancer [19]. In relation to its impact on T2DM, a recent study involving 960 participants with T2DM reported that the MIND diet slowed the decline in global cognition and executive function [16]. Furthermore, scholars found a potential association between a higher MIND score and lower blood glucose levels, although the difference was not statistically significant (participants with MIND scores of 7.5–8.0 versus 6.0–7.5 versus < 6.0: 106 ± 27.8 versus 110 ± 61.2 versus 107 ± 31.5, P-value = 0.47) [20]. The MIND diet shows promise as a potential therapeutic approach to preventing the development of DM. However, to date, no studies made well-elucidations. The MED diet, which forms a significant component of the MIND diet, has been extensively studied in this context. Controlled trials have demonstrated that the MED diet alleviated traditional CV risk factors, including reductions in blood pressure, triglyceride levels, and glucose levels [21, 22]. Long-term reductions in HbA1c levels have also been observed in individuals with DM following adherence to the MED diet [22, 23]. Similar protective effects were also reported in research focusing on the DASH diet [5]. Given that the MIND diet incorporates the MED and DASH diets components and demonstrates several advantages for individuals with DM, it is reasonable to hypothesize that the MIND diet has similar beneficial effects. This study established an inverse association between the MIND diet and the death risk in T2DM patients, suggesting that the MIND diet represents an anti-diabetic dietary pattern.

In addition to its beneficial effects in T2DM patients, the MIND diet has also demonstrated significant value in lingering life expectancy. A recent cohort study included 882 older participants and found an inverse relationship between the MIND score and death risk. The risk of all-cause death was shown to decrease by 12% per unit increase in MIND score during a 12-year follow-up [24]. Furthermore, the CV benefits of adhering to the MIND diet have been highlighted in previous research. In a rigorous prospective cohort study by Mahdieh et al., involving 2863 participants, the impact of the MIND diet on the risk of CV diseases (including coronary heart disease, stroke, and CV mortality) was investigated. The results indicated that a higher MIND score was associated with a reduced risk of CV disease [25]. Additionally, Asma et al. conducted a case-control study with 193 hospitalized stroke cases and 195 hospital-based controls, revealing an inverse relationship between the MIND score and the risk of stroke [26]. Consistent with these previous studies, the present study also identified a significant inverse association between the MIND score and the death risk in the general population, again emphasizing the MIND diet as a healthy dietary pattern.

Subgroup analysis revealed that the benefits of the MIND diet were significantly amplified among older participants (age > 65 years). This finding aligns with a previous study that specifically examined older individuals (mean age 69.5 years) and reported the improved prognosis roles of the MIND diet in this population [24]. Thus, the MIND diet may hold particular therapeutic value for older adults, and further studies are warranted to validate these observations.

Among the components of the MIND diet, it is likely that whole grains, green leafy vegetables, and beans contribute the most to its protective effects. These components have been shown to enhance glycemic tolerance, improve lipid profiles, and reduce inflammation [25]. Additionally, the MIND diet’s restrictions on fast/fried foods, sweets/pastries, and butter/margarine play a role in its protective benefits for individuals with hyperglycemia. These restrictions limit the consumption of substances known to contribute to metabolic disorders, such as added sugar, saturated fatty acids, and trans fatty acids [27]. Further investigation is needed to elucidate this aspect.

IHD is widely recognized as a potential contributor to poor prognosis, and its connection to glucose metabolism and endothelial function has been extensively studied. Recent observational research has confirmed the role of insulin resistance in the progression of IHD across all stages in individuals with normal glucose tolerance, highlighting the significance of glucose metabolism in IHD development [28]. Furthermore, endothelial function has been shown to impact the prognosis of IHD patients. A rigorous randomized controlled trial demonstrated that reducing coronary endothelial dysfunction through metformin therapy was associated with a decreased CV risk in IHD patients [29]. Overall, significant interactions between IHD and glucose metabolism have been well-documented. To mitigate the impact of IHD on prognosis, we performed a sensitivity analysis excluding participants with IHD including MI. The results consistently aligned with the main conclusions, further reinforcing the association between adherence to the MIND diet and reduced risk of mortality. It is important to note that the NHANES dataset used in this study did not provide detailed information on the specific type of MI. Therefore, the current analysis was unable to examine the association of the MIND diet with the prognosis in patients with different types of MI. Future studies are encouraged to investigate this relationship and explore the potential impact of the MIND diet on the prognosis of patients with various types of MI.

Diabetes can lead to inflammation and oxidative stress, which can adversely affect coronary plaques, leading to CV events and death [30]. Hypoglycemic treatments have been reported to reduce CV risk in diabetic patients. In a multi-center study, scholars reported that hypoglycemic therapy like sodium/glucose cotransporter 2 inhibitors (SGLT2-I) was significantly associated with the reduced risk of major adverse cardiac events [31]. Besides, a recent rigorous study also showed that SGLT2i treatment in T2DM is associated with a reduced incidence of in-stent restenosis (ISR) in patients undergoing percutaneous coronary intervention [32]. To minimize the potential impact of hypoglycemic treatment on the prognosis of individuals with diabetes, we conducted a sensitivity analysis excluding participants receiving such therapy. The results demonstrated a significant and robust association between adherence to the MIND diet and a reduced risk of CV mortality. It is important to note that the specific hypoglycemic drugs used and the atherosclerotic plaque stability were not reported due to data limitations in the NHANES dataset. Considering the widely reported CV benefits of SGLT2-I therapy, it would be valuable to investigate the association between the MIND diet and CV mortality by taking into account the potential involvement of SGLT2-I therapies in future studies. Besides, the effect of the MIND diet on atherosclerotic plaque stability was also another interest to be focused on in the future study.

In addition to the hypoglycemic treatment, DAPT and statin therapy were also associated with improved prognosis in diabetic patients [33, 34]. These therapies exert their effects through mechanisms such as anti-thrombotic effects and reduced inflammation in atherosclerotic plaques, leading to plaque stabilization characterized by thickened fibrous caps and macrocalcification [35, 36]. To minimize the potential influence of statins or DAPT treatment on long-term mortality risk, we performed a sensitivity analysis excluding subjects receiving these treatments. The results remained consistent, further reinforcing the robustness of our findings.

Firstly, the diagnosis of T2DM and assessment of MIND scores were based on self-reported questionnaires without verification by specialists, which introduces the possibility of bias. Secondly, the calculation of the MIND score relied solely on food data from an FFQ, and the 24 h recall food data from NHANES could not be used due to differences in units of measurement. This limitation may have affected the accuracy of the MIND scores. Thirdly, the association between the MIND diet score and T2DM was examined using cross-sectional analysis, which does not establish a robust causal relationship. Further studies using longitudinal designs are necessary to address this limitation. Fourthly, this study was limited by the unavailability of data on cardiac function and echocardiogram indices, as these measures were not included in the NHANES dataset. The absence of these variables may have introduced bias in the analysis of CV death risk. At last, the lack of randomized performance limits the strength of the conclusions. Therefore, future exploration of the MIND diet in T2DM should be performed in randomized clinical trials.

Generally, the findings of this study provide valuable insights into the potential protective effects of the MIND diet on the prognosis of T2DM patients. Further research is warranted to confirm and expand upon these findings, reinforcing the importance of exploring the role of the MIND diet in improving outcomes for individuals with T2DM.