To conduct the present review, we consulted two databases to identify the literature: PubMed and PsycINFO, from inception until December 2023. We used the terms “neuroticism” AND “mindfulness” to identify literature with no restrictions regarding population, date or awareness-based interventions.

Articles for selection were recorded using Rayyan, a web-based data synthesis software program (Ouzzani et al., 2016).

From the search using the terms “neuroticism” AND “mindfulness” the articles were selected according to the following inclusion criteria: (i) to be in English or Spanish and (ii) to contain primary outcome measures that assessed neuroticism and/or mindfulness using validated instruments (e.g., FFMQ, MAAS, NEO-PI, or BFI). Articles were excluded if they were in other languages, described as protocols, dissertations, or validations of instruments, or if the primary outcomes were different from mindfulness and/or neuroticism. No awareness-based interventions were excluded.

To summarize the results, we opted for a scoping review that allowed us to organize and synthesize the main findings. Following the recommendations of Aveyard (2014) and other published reviews (McVeigh et al., 2021), we analyzed our articles’ main findings, identified the themes that would allow us to answer our research questions, and to summarize the results, outline the relationship between the evidence, and draw conclusions. The scoping review was conducted by two independent reviewers using pretested forms.

The 49 studies selected for the present review (see Table 1) took place in different countries (Australia, Canada, China, Iran, Italy, Denmark, Germany, the Netherlands, New Zealand, Norway, Spain, Taiwan, the UK, and the USA), resulting in a total sample drawn from several different cultures. The sample sizes of the studies ranged from 34 to 2,548 participants (n = 17,451), with a mean age of 32.25 years (range from 14.44 to 72.4 years). A percentage of 81.11 of the sample was women, except for one study that included an all-male sample (Lee and Bowen, 2015). The samples comprised students, volunteers from the community, or mixed volunteers from the community with a specific pathology and adolescents. Most of the included studies used a cross-sectional design, while others were randomized controlled trials, longitudinal studies, quasi-experimental studies or other types (the design of each study is indicated in Table 2).

The final 49 studies were grouped and presented over the following sections, starting with the relationship between neuroticism and mindfulness reported in the studies that assessed neuroticism and/or mindfulness using validated instruments. Next, we describe the relationship of these two dimensions and the mindfulness facets with mental health; more specifically with depression, anxiety, posttraumatic stress syndrome and borderline personality disorder. The relationship of mindfulness and neuroticism have been also studied in regard with cognitive impairments; these results are presented in the next section. The last two sections refer to those studies evaluating the effects of Mindfulness-Based Stress Reduction Program (MBSR), and the other mindfulness-based interventions used in the studies included (MBIs, section five).

Although all eight studies (Table 2) used different sets of instruments, similar results reported a significant negative correlation, indicating that high mindfulness was associated with low neuroticism (Quintana et al., 2017). When comparing the neuroticism scores between meditators and non-meditators, even if there were no significant differences between the two groups, more experience on meditation was negatively correlated with neuroticism, and this relationship was mediated by the mindfulness facets “acting with awareness” and “non-judging” (van den Hurk et al., 2011). Accordingly, when assessing neuroticism and mindfulness at 4-time points over a year in a sample of undergraduate students, mindfulness was found to be negatively correlated with neuroticism (Wang et al., 2022).

Mindfulness states, particularly emphasizing facets such as self-awareness (“Acting with Awareness”) and emotional processing (“Non-Judgmental Acceptance”) seem to be linked to negative affect and underscored that personality traits and behavioral inhibition did not affect nor predict changes in emotional affect after the exposure to a negative stimulus. The authors posited that a potential constraint lay in the contextual backdrop of the study, coinciding with the onset of the COVID-19 pandemic. They propose that participants, undergraduate students, may have already experienced elevated initial stress levels, potentially masking the underlying connections between personality traits and negative affect (Karl et al., 2021).

Mather et al. (2019) reported negative correlations of three mindfulness facets, non-judging, non-reactivity, and acting with awareness, with all neuroticism components (anxiety, anger, hostility, depression, impulsiveness, vulnerability, and self-consciousness). Consistently, Hanley (2016) outlined the “self-regulation cluster,” which is composed of self-regulation skills associated with three mindfulness facets (non-judging, non-reactivity and acting with awareness) that are negatively correlated with neuroticism. Another study examining the association of mindfulness facets with specific neuroticism aspects (anxiety, anger, depression, self-consciousness, immoderation, and vulnerability) reported that three mindfulness facets were negatively correlated with anxiety, depression and vulnerability, but not with the other neuroticism components. Moreover, the facets observing and describing showed no relationship with anxiety and depression, which aligns with other work showing no relationship between observing and broad neuroticism (Iani et al., 2017).

Furthermore, an investigation of the relationship between the Five-Factor Model and everyday mindfulness (e.g., being mindful during everyday activities) and mindfulness during meditation (e.g., formal meditation practice) revealed that there were no significant differences between the types of mindfulness (Thompson and Waltz, 2007). Haliwa et al. (2021) assessed mindfulness using multiple questionnaires (FFMQ, CAMS-R, and MAAS) and found that all mindfulness measures were negatively correlated with neuroticism, thus strengthening the evidence for this relationship.

Iani et al. (2017) assessed the dimensions of mindfulness and their relationship with psychological well-being and neuroticism and found that neuroticism had a positive correlation with depression and anxiety, while a negative relationship with all facets of mindfulness (except for the “observe” and “describe” facets) and psychological well-being. In adolescents, acting with awareness and non-judging was negatively correlated with depression, maladaptive schemes, stress, and neuroticism (Calvete et al., 2020). More specifically, the authors identified a profile of adolescents that exhibited the lowest scores in non-judgment and acting with awareness and who experienced higher levels of depressive symptoms, maladaptive schemes, stress, and neuroticism; as a result, their psychobiological adjustment was poorer among older adolescents. Another profile of adolescents displayed higher scores in acting with awareness and non-judging, and lower scores in observing and non-reactivity; as a result, they exhibited better psychobiological adjustment, characterized by fewer maladaptive schemes, less stress, and less neuroticism.

When Gautam et al. (2019) assessed the presence of anxiety and distress, similar results were obtained. Increased anxiety and neuroticism and decreased mindfulness scores were related to increased procrastination among undergraduate students. Furthermore, Drake et al. (2017) found that non-specific psychological distress was positively correlated with neuroticism and a negatively correlated with mindfulness, which predicted the presence of non-specific distress. Likewise, Dixon and Overall (2016) found that university students who were more “mindful” reported less depressed mood scores even on stressful days, and that daily stress seemed to have a greater impact on depressed mood when individuals scored high on neuroticism, depressive symptoms, and emotional regulation difficulties.

Several studies have confirmed a positive correlation between neuroticism and depressive symptoms and a negative correlation between neuroticism and mindfulness (Feltman et al., 2009; Barnhofer et al., 2011). Neuroticism was also a predictor of depressive symptoms in a study of adolescents who had experienced a tornado (An et al., 2019), and a predictor of depression, anxiety, and stress in a sample of university students (Karing, 2021). In contrast, mindfulness predicted an opposite relationship with depression, anxiety, and stress during the first COVID-19 lockdown in a later study (Karing, 2021). Additionally, neuroticism scores assessed 6 years before assessing depressive symptoms correlated with the severity of current depressive symptoms in a longitudinal cohort study (Barnhofer et al., 2011). It should be noted that in this study, the predictive value of neuroticism on depressive scores was significant when participants displayed low and moderate mindfulness scores. Similarly, Feltman et al. (2009) reported that higher levels of depression were present in a sample that displayed higher levels of neuroticism and less mindfulness, while a study assessing more severe depressive symptoms in a sample of university students reported a positive correlation between the appearance of suicidal ideation and neuroticism and a negative correlation between suicidal ideation and mindfulness (Tucker et al., 2014).

In a cross-sectional study of participants with recurrent depression in remission, which assessed the mindfulness dimensions associated with personality domains and implicated in the relapse of depression, Spinhoven et al. (2017a,b) reported that non-judging, non-reactivity, and acting with awareness skills, described as the “self-regulation factor,” correlated with less expression of neuroticism in terms of depression, anxiety, and impulsiveness.

Regarding trauma-related outcomes, neuroticism was a significant predictor of post-traumatic stress disorder (PTSD) in adolescents who had experienced a tornado (An et al., 2019). Boelen and Lenferink (2018) evaluated the association between experiential acceptance, mindfulness and “analog PTS”—understood as post-traumatic stress associated with negative life events (e.g., mental/physical illness of others, relationship break up, serious interpersonal conflict…), but not compliant with formal PTSD criteria—and their relationship with neuroticism in university students. They found positive correlations between neuroticism and analog PTS, worry, and rumination, and a negative correlation with mindfulness.

On the other hand, Polizzi et al. (2023) assessed the impact of a mass traumatic event and the experience of COVID-19-related stress (CS). Their results indicated that neuroticism was a significant factor explaining CS and that certain mindfulness facets, such as acting with awareness and non-judging, may play an important role in reducing or preventing stress responses.

In contrast, Elices et al. (2015), assessed the relationship between mindfulness, neuroticism, and childhood maltreatment in a sample of outpatients from a borderline personality disorder (BPD) unit, and found that neuroticism-anxiety was negatively correlated with acting with awareness, non-judging, and non-reactivity. This negative association indicated that neuroticism and impulsive sensation seeking were predictors of non-judging, and that neuroticism was also predictive of acting with awareness. In the same study, sexual abuse was correlated with mindfulness deficits, with a negative impact on acting with awareness, and difficulties being present-oriented instead of being more judgmental-oriented, which is a characteristic of BPD.

Similarly, Wupperman et al. (2008, 2009) assessed the relationship between mindfulness deficits and BPD features (e.g., difficulties with emotional regulation, interpersonal effectiveness, and impulsivity). First, they evaluated a student sample without BPD and found that mindfulness was positively correlated with interpersonal effectiveness and negatively correlated with impulsivity, emotional regulation, and neuroticism. Subsequently, they evaluated a sample of psychiatric inpatients and found similar results, confirming that mindfulness deficits are predictors of the expression of BPD (Wupperman et al., 2008).

Assessing behavioral regulation, a related outcome, Fetterman et al. (2010), found that in undergraduate students, neuroticism was negatively correlated with behavioral regulation variables such as self-control, and positively correlated with impulsivity, while higher mindfulness predicted less impulsivity and neuroticism, and more self-control. In relation with this, a core component of successful emotional regulation is the ability to identify and describe our feelings, in contrast with the inability to process emotional information and difficulties in emotional regulation which is known as alexithymia. Related to this, Heshmati and Pellerone (2019) found that alexithymia correlated negatively with dispositional mindfulness and positively with neuroticism and that neuroticism predicted the presence of alexithymia. Additional details can be found on Table 3.

Latzman and Masuda (2013) evaluated students to study the relationship between mindfulness and psychological inflexibility, understood as a rigid psychological reaction characterized by experiential avoidance and diminished daily function, and associated with depression, anxiety, and general distress. The results indicated that participants who scored higher on neuroticism displayed greater psychological inflexibility, whereas those with higher mindfulness scores displayed less psychological inflexibility.

Kowalski and Schermer (2019) assessed hardiness, characteristic of individuals who remain healthy under stressful conditions. Hardiness is characterized by the belief that one can influence events, commitment to activities, and a tendency to alter the cognitive appraisal of stressful events from negative to positive, viewing them as challenges to be overcome. The authors found that hardiness was negatively correlated with rumination, worry, anxiety, and neuroticism and positively correlated with mindfulness and health outcomes. However, when neuroticism was controlled for the analyses, the relationship between hardiness, rumination, and health was not significant, and the level of significance of the correlations between hardiness, mindfulness, anxiety, and worry was attenuated.

Additionally, Kondracki et al. (2021) reported in that college students that higher neuroticism scores were associated with lower mindfulness and higher everyday cognitive failures. In line with this, Hou et al. (2022), found that neuroticism was positively correlated with depression and negatively with dispositional mindfulness and cognitive reappraisal in postgraduate students. Chen et al. (2023) found that the level of neuroticism exhibited a positive correlation with negative emotion regulation. Negative cognitive bias served as a mediator in the relationship between neuroticism and emotion regulation, while mindfulness played a mediating role in the relationship with negative cognitive bias, forming a sequential connection.

Pérez-Yus et al. (2020) evaluated the role of mindfulness and its association with negotiation effectiveness in an adult sample and found that negotiation effectiveness was positively correlated with age, emotional intelligence, mindfulness, several personality domains (E, O, and C), motivation, and style of negotiation, whereas it was negatively correlated with neuroticism. Furthermore, the results indicated that people who meditated more displayed increased clarity (emotional intelligence), greater mindfulness, less neuroticism, and greater effectiveness in negotiation. Additional information can be found in Table 4.

MBSR is the most used intervention. In university samples, the results indicated positive effects; MBSR lowered mental distress and study stress and improved subjective well-being as baseline neuroticism increased (de Vibe et al., 2015). Similarly, Halland et al. (2015) reported that following a MBSR intervention, students used more problem-focused coping, and those displaying higher neuroticism scores reduced avoidance coping and increased seeking social support. Moreover, mindfulness training decreased neuroticism and psychological distress during the 6-year follow-up period, and this decrease was associated with reduced psychological distress at the 6-year follow-up (Hanley et al., 2019). Finally, Van Dijk et al. (2015) assessed the interest in participating in a MBSR training and found that interested participants reported higher levels of psychological distress and neuroticism. Furthermore, those who participated displayed lower baseline mindfulness skills compared to non-participants in the training, which could be explained by sampling bias.

The effects of training were also tested in volunteers from the community, and the results were similar. Nyklíček and Irrmischer (2017) assessed the effect of personality on mood changes after MBSR training and found that neuroticism was associated with benefits3 in the reduction of anxiety and depressed mood. Similarly, Smith et al. (2008) compared MBSR with an intervention based on cognitive behavioral stress reduction and found that those participants in the MBSR group displayed higher scores on mindfulness and well-being, and a reduction in perceived stress, depression, and neuroticism than those in the other group. A similar pattern was reported by Jagielski et al. (2020) in a sample of women with breast cancer; the results after the MBSR training indicated that women displaying low conscientiousness (e.g., being relaxed, adaptable, spontaneous) and high neuroticism, reported less distress at 12-month follow-up.

Finally, Elliot et al. (2019), who reported baseline scores before the intervention—found that higher scores of mindfulness were associated with fewer depressive symptoms, negative affect, physical symptoms, and better sleep quality; however, the association of higher mindfulness with fewer depressive symptoms was only significant when the participants displayed higher levels of neuroticism, and neuroticism did not interact with the rest of the outcomes. Additional details have been summarized in Table 5.

Armstrong and Rimes (2016) used MBCT to compare its efficacy with an online self-help intervention in a sample of university students and staff with high neuroticism. Participants in the MBCT group reported significantly lower levels of neuroticism and rumination, as well as higher levels of self-compassion and decentering (the ability to observe thoughts and feelings as passing mental events) than participants in the online self-help group. There were no changes in levels of depression or anxiety. Another study examining the long-term effects of MBCT compared to internet-based MBCT in a sample of distressed cancer patients indicated that less psychological distress, rumination, and neuroticism at baseline predicted less psychological distress at follow-up in both interventions. The intervention also improved the mental health-related quality of life and positive mental health (Cillessen et al., 2018). Finally, Spinhoven et al. (2017b) analyzed whether MBCT predicted long-term changes in personality and found a significant reduction in neuroticism scores. Additionally, improvements in mindfulness skills predicted changes in neuroticism, and acting with awareness was associated with these changes.

Other nonstandard mindfulness-based interventions. The impact of a single session of mindfulness meditation, regardless of its duration, enhanced state mindfulness. Surprisingly, neuroticism does not mediate these effects (Palmer et al., 2023).

Another study explored the effects of adapted mindfulness training on the well-being of graduate students and reported that the intervention caused a significant reduction in neuroticism, while the effect on mindfulness facets was found only in a subsample (Crone et al., 2023).

Participants trained in mindfulness-oriented meditation (MOM) (based on MBSR, sessions included a 30 min discussion followed by 30 min MOM meditation) reported higher mindfulness scores and decreased neuroticism scores and burnout levels vs. participants on a waiting list in an all-female sample of teachers (Fabbro et al., 2020). By contrast, Lee and Bowen (2015) tested a mindfulness-based training program in an all-male sample of incarcerated men receiving drug abuse treatment. The treatment content included the core components of mindfulness, relapse prevention, and a balanced lifestyle. However, contrary to their own hypothesis, the post-intervention results indicated lower levels of curiosity and decentering and revealed an unexpected positive correlation between mindfulness and neuroticism.

Oken et al. (2017) assessed the effects of mindfulness meditation (MM) vs. a waitlist control in a sample of mildly stressed adults. The intervention lasted 6 weeks and was carried out one-on-one, in contrast to the typical group setting. The results indicated no change in cognitive measures, sleep, positive affect, physiological outcomes (e.g., salivary cortisol, health rate), or, surprisingly, mindfulness measures. However, MM improved negative affect, stress, mental health component, and self-efficacy.

Finally, Jacobs et al. (2011) conducted an experiment that compared a 3-month meditation retreat with a waitlist control to test its effects on telomerase activity, stress, and neuroticism. The intervention was intense and was conducted in an isolated retreat setting; it included two daily group-guided meditations followed by a mean of 6 h solitary meditation during the day and had a weekly individual meeting with an experienced practitioner. The authors reported a significant increase in mindfulness, perceived control, and telomerase activity (measured after treatment), and a decrease in neuroticism in the retreat group compared to the waitlist control group. Additionally, participants who reported less favorable psychological functioning at baseline showed greater improvements post-intervention. Complementary information can be found in Table 6.

Consistent findings across various studies indicate that when neuroticism scores are high, mindfulness scores tend to be low, and vice versa. This relationship has been corroborated across different populations of all ages and in several countries. Neuroticism and mindfulness are related to diverse mental health outcomes. Neuroticism shares core characteristics with anxiety and depressive symptoms (Jylhä and Isometsä, 2006) and is a predictor of mental health symptomatology (Newton-Howes et al., 2015). Studies related to emotional and behavioral regulation and psychological inflexibility, once again common characteristics of neuroticism and core components of several mental health problems, are also supported by previous evidence (Paulus et al., 2016).

Giluk (2009) reported that neuroticism is the personality trait most strongly related with mindfulness. Subsequent studies have identified a common pattern of high scores in facets such as “acting with awareness,” “non-judging,” and “non-reactivity,” which have been identified as the “self-regulation cluster” (Hanley, 2016) or “unbiased awareness” (Elices et al., 2015; Spinhoven et al., 2017a,b; Mather et al., 2019; Calvete et al., 2020). These “clusters” have been linked to improved physical and psychological health and coping strategies (Beaulieu et al., 2022; Zhu et al., 2020). However, the possibility that this negative relationship may in all circumstances cannot be ruled out. Since some authors have reported an unexpected positive correlation between mindfulness and neuroticism, further work needs to be done in larger samples to improve understanding of these relationships, both in broad terms and specifically between the mindfulness dimensions and neuroticism components.

Most characteristics of neuroticism correlate with the expression of, predict, or worsen diverse mental and physical health problems. MBIs have shown that training core components can help alleviate or improve symptoms; if not, they can help people suffering from these conditions to manage them or cope with them more adaptively.

Additionally, we assessed the impact of MBIs on other health outcomes (e.g., depression, anxiety, cognitive outcomes). Despite the heterogeneity, the results were mainly consistent across the outcomes.

MBIs were useful for improving symptom management and stress-related disease outcomes in different patient populations, suggesting that these benefits can come from increasing stress resilience pathways in the brain and regulating stress reactivity (hypothalamic pituitary adrenal and sympathetic adrenal medullary axis) (Creswell et al., 2019). Both dispositional and trained mindfulness, can improve patient-reported symptoms across different diagnoses. It is becoming clear that the benefit of mindfulness training comes from the acquisition of coping abilities to deal with ailments, including making conscious healthy decisions and reducing habitual reactions (Greeson and Chin, 2019).

Studies have demonstrated that MBIs significantly affect alexithymia, enhancing awareness of emotions, curiosity about inner experiences, and connection with one’s thoughts and feelings (Norman et al., 2019). Evidence, although limited, indicates that MBIs are promising for treating trauma-related outcomes, such as PTSD, helping individuals tolerate their physical and emotional distress and reduce their hyperarousal symptoms (Niles et al., 2018). Similarly, MBI have proven effective in reducing depression and anxiety among individuals diagnosed with anxiety disorders (Sevilla-Llewellyn-Jones et al., 2018). A Meta-Analytic review with 998 participants examined the effects of MBIs on biomarkers in psychiatric illness, results showed low but significant effects on health status related to biomarkers of low-grade inflammation (Sanada et al., 2020).

Recent studies have explored the long-term effects of mindfulness on mental health, revealing outcomes in areas such as depression, anxiety, and stress management. For instance, a study evaluated the -short, −medium and long-term efficacy of a combined mindfulness intervention (face-to-face intervention plus app), a face-to-face mindfulness intervention alone, and a mindfulness app alone, compared with an active control group (communication training) during the COVID-19 pandemic. The results indicated improvements in mindfulness, emotional regulation and attentional skills up to 12 months after the intervention. In contrast, no significant differences were found between the groups on measures of stress or mental health (anxiety or depression) in the long term. But both the intervention groups and the active control group improved in anxiety in the short and medium term. For depression, only a significant time effect was observed4 months after the intervention. In addition, it was observed that greater use of the mindfulness app could negatively affect stress (Karing, 2024). Another study indicates that a short-term MBI and active control group (relaxation training) improved trait mindfulness and psychological well-being compared with an inactive wait-list group. However, no group differences were found on any of the other variables like decentering depression, anxiety, executive attention, and coping style (Josefsson et al., 2014). A systematic review suggests that MBI’s was effective in reducing stress in the short term, but not in the medium or long term, showing a small effect on stress reduction over a 3-month period. Nevertheless, no significant evidence was found for stress reduction from 3 months onwards (Sosa-Cordobés et al., 2022). This indicates that other strategies, such as ongoing booster sessions, are needed to maintain improvements in the long term.

Research supports the benefits of MBIs not only on emotional and behavioral regulation and psychological inflexibility, common features of neuroticism, but also that mindfulness emerges as a significant moderator in the relationship between self-control and psychological symptoms. This suggests that a mindful approach complements self-discipline in improving mental health (Bowlin and Baer, 2012).

In this respect, greater degree of mindful awareness may buffer the effects of psychological inflexibility on distress variables, particularly somatization and anxiety (Masuda et al., 2022). For example, a brief-MBI integrated into a school curriculum enhanced children’s socio-emotional and academic development. Positive changes in dispositional mindfulness led to reductions anxiety and psychological inflexibility. The authors discuss that dispositional mindfulness and emotion regulation work as processes of change that underlie the intervention’s impact (García-Rubio et al., 2023). A longer intervention improved executive functioning measures related to susceptibility to cognitive interference and working memory in high school students (Frank et al., 2021).

Both MBIs and CBT, along with Acceptance and Commitment Therapy (ACT), emphasize that people should focus on the way they relate to their symptoms or thoughts instead of trying to eliminate them, without identifying with them and in a kind manner. They are thus grouped under what are known as third-wave cognitive-behavioral therapies (Hayes, 2004). These combined therapies can help patients observe their thoughts from a more distanced and less reactive perspective, without getting caught up in them. Similarly, accepting thoughts and emotions without judging or trying to change them immediately helps individuals with neuroticism avoid internal struggles against their emotional experiences. Identifying levels of neuroticism and adjusting interventions accordingly—such as allowing them to choose between guided or silent meditation, or different types of practices like walking meditation or mindful yoga - can be beneficial. Introducing mindfulness practices gradually, starting with short sessions and increasing the duration as participants become more comfortable, can make MBIs more effective. Dialectical Behavior Therapy (DBT), the gold-standard treatment for Borderline Personality Disorder (BPD), integrates behavioral and mindfulness practices (focusing on the ability to manage emotions, tolerate distress, and improve interpersonal relationships), putting a particular focus on acceptance (Stiglmayr et al., 2014). Similarly, mindfulness-based cognitive therapy (MBCT) and mindfulness-integrated cognitive behavior therapy (MiCBT) are transdiagnostic approaches that focus on reducing avoidance and addressing interoceptive deficits and emotional reactivity. Accordingly, focusing on shared factors across psychological disorders and using transdiagnostic treatment protocols instead of multiple single disorder protocols can be a more resource-efficient approach for addressing comorbidity (Francis et al., 2024).

A systematic review examined the long-term effects and durability of mindfulness-based interventions (MBCT and MBSR) on mental health and well-being, using mediation analysis methods. Evidence was identified that mindfulness, rumination, and worry are significant mediators of the effects of MBIs on mental health outcomes, supporting the key theoretical premises underlying MBSR and MBCT. These findings suggest that cultivating mindfulness skills leads to understanding and acceptance of one’s own experience (Gu et al., 2015).

Despite all the promising and positive findings, several limitations must be considered, and this review must be interpreted with these limitations in mind. Owing to the design of our review, we did not conduct a strict quality assessment of the studies, but there are some concerns that need to be discussed.

Currently, there is still debate about the conceptual and operational definitions of what “mindfulness” is and is not. MBI’s designed in one practice context may not be applicable in other contexts, because meaning is not transferred between settings. A scoping review identified four themes central to the concept of mindfulness, corresponding to the four domains of mindfulness research: mental health, behavioral change, cognitive neuroscience, and ethical mindfulness. However, operational definitions of mindfulness are not clearly articulated within these domains. Authors suggest greater attention should be given to developing operational definitions specific to each research domain, to avoid differing practices and definitions resulting in varied outcomes and benefits (Phan-Le et al., 2022).

Several methodological concerns were identified despite many of them not being new and having already been addressed (Davidson and Kaszniak, 2015). More than half of the included studies had an observational design, preventing causal inferences. Experimental studies often lacked follow-up assessments, had selection biases, or did not include active control groups. Moreover, most studies relied on self-reported measures, which introduced potential biases (e.g., social desirability and lack of objectivity). Along the same line, the heterogeneity of the instruments might complicate the task of comparing the results reported in the selected studies and once again reduce the generalizability of the findings. Several studies (Lee and Bowen, 2015; Iani et al., 2017; Heshmati and Pellerone, 2019; Kowalski and Schermer, 2019; Calvete et al., 2020) have also reported some concerns regarding the use of mindfulness instruments, as they were not certain that the instruments were assessing their desired outcome or were valid (Latzman and Masuda, 2013). As is the case with the FFMQ which gives a multifaceted view of mindfulness, compared with the MAAS that focus on a more general assessment of mindful attention, this fact may be contributing to inconsistent results (Hanley and Garland, 2017).

Sample characteristics also posed limitations. Participants were mostly young, educated, Caucasian females, limiting the generalizability of the findings. Future research should aim for more diverse samples and consider recruiting more male participants and individuals from various cultural backgrounds in mindfulness research (Bodenlos et al., 2017). It would be helpful to carry out interventions in areas traditionally dominated by men or male-oriented cultures, to recruit more male participants. An example is the study of the effects of an MBI on physiological and psychological criteria in a non-selective sample of police officers, where the results showed that participants with higher neuroticism and openness benefited more, and the effectiveness was greater for those who perceived a favorable social norm toward MBIs (Krick and Felfe, 2020). Furthermore, adapting MBIs for racial and ethnic minoritized communities could potentially make them more relevant and acceptable (Morales and Burnett-Zeigler, 2024). Low adherence to interventions among young people might be improved by incorporating technological supplements to the IMB, making the implementation more attractive and better suited for other study populations (Lucas-Thompson et al., 2020).

We believe it is crucial to focus mindfulness-based interventions on young adulthood (typically defined as mind-20 s), once brain maturation is largely complete. The prefrontal cortex, which plays a key role in emotional regulation and the modulation of personality traits like neuroticism, reaches full development during this period. Neuroticism predisposes individuals to depression by increasing the likelihood of ruminative responses to low mood (Barnhofer et al., 2011). Research indicates that mindfulness training can foster emotional regulation skills, reducing emotional reactivity and rumination, which are hallmark features of neuroticism (Kuehner et al., 2023). Introducing these interventions at this stage of life can be an effective preventive strategy to mitigate the manifestation of neuroticism throughout life.

Therefore, we recommend that mental health policies and professional practices incorporate mindfulness programs into educational and healthcare settings, specifically targeting young adults. This approach can help reduce the negative impact of neuroticism on mental health across the lifespan.

In the general adult population, facilitating the formation of practice groups where participants can share their experiences and support each other can be beneficial for improving adherence and overall well-being. Additionally, sampling methods were a limitation and likely a source of bias, as most studies used convenience samples. In the case of students, participation was compensated with academic credits. When sampling for experimental studies, there was a self-selection concern, as some studies recruited participants from populations that already had an interest in MBI interventions.

Future research should focus on developing high-quality, including randomized controlled trials, long-term follow-ups, recruiting larger and diverse samples, and exploring objective measures, to address these limitations.