Autism Spectrum Disorder and Gut Health: Contributions of Naturopathy for an Integrative Perspective

Journal of Complementary Therapies in Health ISSN 2975-9323 |eISSN 2975-9552 Journal of Complementary Therapies in Health 2025:3(3). doi:10.5281/zenodo.17776899 institutoptc.com/journal-complementary-therapies Review Autism Spectrum Disorder and Gut Health: Contributions of Naturopathy for an Integrative Perspective. Maria Carreira1*, Teresa Esteves1, Rui Afonso2, and Tânia Almeida1. 1 IPN – Portuguese Institute of Naturology, Porto, Portugal; 2 Independent researcher. * Correspondence: [email protected] Abstract Background: Autism Spectrum Disorder (ASD) is a neurodevelopmental condition associated with alterations in social communication, behaviour, and sensory processing. Recent studies indicate that the gut microbiota plays a crucial role in modulating the gut-brain axis, influencing neurological development and behaviour. Objective: This monograph explores the relationship between gut health and ASD, investigating how naturopathic interventions can help manage ASD symptoms. Methodology: The study focused on a review of scientific evidence regarding these interventions and their effectiveness in modulating the gut microbiota, regulating inflammation, and improving gastrointestinal and behavioural symptoms. Scientific articles in Portuguese and English were collected from both national and international sources, published between 2019 and 2025, across various databases. Results: From the literature review, it was found that individuals with ASD often exhibit a dysbiotic gut microbiota profile, associated with altered production of key metabolites such as short-chain fatty acids, tryptophan and choline derivatives, neurotransmitters, and inflammatory compounds, which directly or indirectly influence brain function, behaviour, and the immune system. Conclusion: Although the mechanisms involved in autism are complex and multifactorial, the data presented suggest that modulating the gut microbiota and strengthening the body’s antioxidant defences may contribute to reducing neuroinflammation, improving intestinal permeability, and optimising brain function. Keywords: Autism Spectrum Disorder; Gut-Brain Axis; Gut Microbiota; Dysbiosis; Naturopathy; Nutraceuticals; Neuroinflammation; Oxidative Stress. 1. Background ASD is a neurodevelopmental condition associated with alterations in social communication, behaviour, and sensory processing 1. The relationship between the gut microbiota and ASD has been the subject of several studies, highlighting the importance of individualised approaches in the understanding and treatment of autism. Naturopathy, by considering the individual as unique, aligns with this perspective, especially in recognising the uniqueness of the gut flora in people with ASD. The symptomatology present in ASD is influenced by cerebral alterations and an inflammatory sensitisation of the blood-brain barrier 2. Considering the uniqueness of the gut microbiota in patients with ASD, it is essential to perform personalised evaluations that consider factors such as antibiotic use, eating habits, exposure to toxic substances, and lifestyle. These evaluations can aid in identifying specific imbalances in the microbiota and in developing therapeutic strategies adapted to individual needs. Citation: Carreira M., Esteves T., Afonso R., Almeida T. Autism Spectrum Disorder and Gut Health: Contributions of Naturopathy for an Integrative Perspective. Journal of Complementary Therapies in Health. 2025;3(3) 10.5281/zenodo.17776899 Academic Editor: Jorge Rodrigues Received: 28 August 2025 Reviewed: 16 September 2025 Revised: 29 September 2025 Accepted: 30 September 2025 Published: 2 October 2025 Publisher’s Note: IPTC stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. Copyright: ©2025 by the authors. Submitted for open access publication under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/). Journal of Complementary Therapies in Health 2025: 3(3). 2 of 9 Carreira M., Esteves T., Afonso R., Almeida T. Autism Spectrum Disorder and Gut Health: Contributions of Naturopathy for an Integrative Perspective. doi:10.5281/zenodo.17776899 This study intends to explore the relationship between gut health and ASD symptomatology, through a review of scientific evidence on naturopathic interventions and their effectiveness in modulating the gut microbiota, regulating inflammation, and improving gastrointestinal and behavioural symptoms. 2.1. Characterisation of Autism Spectrum Disorder ASD is a neurodevelopmental condition characterised by deficits in social communication and interaction, repetitive behaviours, and atypical sensorimotor patterns 1. The growing prevalence of ASD has driven significant advances in research focused on understanding its aetiology, prevention, and mitigation of its impact 3. Scientific literature suggests that early diagnosis and intervention can improve outcomes in individuals with ASD. However, the causes remain complex and unclear, and currently there are no specific clinical biomarkers for this disorder 4. This ongoing effort requires constant updates to the body of knowledge and the identification of factors yet to be explored 3. Although the DSM-5 does not advocate specific interventions, its clinical framework allows naturopathic professionals to understand the symptomatic and functional spectrum of this condition. This understanding is fundamental for developing complementary and personalised approaches that respect the individual characteristics of the person with ASD, particularly regarding diet, gut microbiota, management of oxidative stress, sensory integration, and psychosocial support. 2.2. Naturopathic Interventions in ASD Naturopathy, as an integrative and holistic therapeutic approach 5,6, interprets the symptoms of ASD in a distinct way from conventional medicine. In addition to neuropsychiatric diagnostic criteria, naturopathy seeks to understand the body as an interconnected whole, identifying underlying causes that may contribute to the symptoms. According to Naturopathy, ASD symptoms are influenced by cerebral alterations and an inflammatory sensitisation of the blood-brain barrier. Through enteroendocrine cells, vagal afferent nerve fibres can identify the composition in the intestinal lumen and sensitise the brainstem, allowing for the detection of alterations in individuals with ASD 2. Intestinal dysbiosis and the gut-brain axis Naturopathy supports that alterations in the gut microbiota (imbalances in beneficial and pathogenic bacteria) directly affect the central nervous system 7,8. The gut microbiota plays an essential role in regulating communication between the gut and the nervous system, influencing gastrointestinal balance and higher cognitive functions 7. The brain-gutmicrobiome axis includes the central nervous system, the enteric system, and various neural, metabolic, endocrine, and immunological mediators. It is the communication between these systems that allows the brain and gut to influence each other 9. The gut microbiota is a set of microorganisms that live in the gastrointestinal tract and provides signalling metabolites essential to host physiology. The gut microbiota and the host establish a complex communication that is influenced by environmental conditions, interacting locally and systemically. Due to the diversity of the gut microbiota and intestinal microbial genes, the gut microbiota produces many structurally distinct metabolites. These metabolites transit between intestinal microorganisms and between intestinal microorganisms and hosts, thereby exerting a wide range of bioactivities to modulate the functions of both the gut microbiota and the hosts 10. Emerging evidence indicates that the health-promoting effects of ingested dietary components depend, in part, on their absorption and metabolism in the upper and lower gastrointestinal tracts, as well as on the host's intestinal microbial composition. Various dietary components, such as polyphenols, are poorly absorbed in the upper intestinal compartments and are extensively metabolised by the colonic microbiota, resulting in the production of a variety of metabolites. These microbiota-mediated products possess specific solubility, reactivity, bioavailability, and biological activities. However, identifying Journal of Complementary Therapies in Health 2025: 3(3). 3 of 9 Carreira M., Esteves T., Afonso R., Almeida T. Autism Spectrum Disorder and Gut Health: Contributions of Naturopathy for an Integrative Perspective. doi:10.5281/zenodo.17776899 and characterising a wide range of metabolites is challenging due to the high chemical diversity of dietary components and the inter-individual variability of the gut microbiota 11. In a healthy state, gut microbiota metabolites are useful for maintaining hosts' basic functions, but inefficient production of these metabolites can lead to numerous metabolic, cardiovascular, gastrointestinal, neurodegenerative diseases, and cancer 10. Individuals with ASD frequently present with poor gastrointestinal health, including problems with intestinal motility, autoimmune responses and/or other adverse reactions to certain foods, as well as deficits in the absorption of essential nutrients. These issues may be caused or aggravated by restrictive behavioural patterns (e.g., preference for sweet and salty foods and/or refusal of healthy foods). Individuals with gastrointestinal problems tend to exhibit more behavioural changes (such as irritability, agitation, hyperactivity) and also usually have an imbalance in the overall composition of the gut microbiota, thus corroborating several studies that implicate the gut-brain pathways as potential mediators of behavioural dysfunction 12. In the bibliographic review by Liu et al. 10, the authors summarised the main metabolites of the gut microbiota and their roles in health and diseases (Table 1). Table 1. Key metabolites present in the gut microbiota and their roles in health and disease (adapted from Liu et al. 10). Group Typical Metabolites Typical Targets Specific Functions Associated Diseases Short-chain fatty acids (SCFAs) Acetate, propionate, butyrate, hexanoate, isovalerate, isobutyrate, 2-methylpropionate, valerate GPR41, GPR43, GPR109A, GPR81, GPR91, HDAC1, HDAC3 Regulation of microbiota composition, intestinal barrier integrity, appetite, energy homeostasis, intestinal hormone production, circadian rhythms, immune response Diabetes, obesity, ulcerative colitis, Crohn's disease, colorectal cancer, autism, Parkinson's, asthma, diarrhoea Bile Acids Cholates, deoxycholic, taurocholate, etc. FXR, VDR, PXR, CAR, TGR5, S1PR2, FPR, mAChR Lipid and vitamin absorption, intestinal immunity, motility, lipid and glucose homeostasis Cholangitis, obesity, liver disease, Alzheimer's, stroke Gases H₂S, H₂, CO₂, CH₄, NO Guanylate cyclase, target proteins via sulfidation Intestinal motility, epithelial secretion, inflammation, mucosal blood flow Parkinson's disease, colitis, ulcer Tryptophan and indole derivatives Indole-3-lactic acid, indole acetic acid, serotonin, etc. AhR, PXR Biofilm formation, drug resistance, intestinal barrier, hormone secretion Colitis, stroke, autism, Alzheimer's, migraine Choline Metabolites TMA, dimethylamine, etc. NF-κB, PKC, NLRP3 (no known direct target) Inflammation, mitochondrial dysfunction, thrombosis, cardiac hypertrophy Liver disease, atherosclerosis, diabetes, heart failure Vitamins B2, B3, B5, B6, B9, B12, K Vitamin receptors Cellular metabolism, immunity, cell proliferation Schizophrenia, autism, dementia Neurotransmitters Dopamine, catecholamines, 5-HT, GABA Adrenergic receptors, 5-HT, GABA Motility, memory, stress, immunity Parkinson's, autism Lipids Conjugated fatty acids, cholesterol, lipopolysaccharides TLR4 Systemic inflammation, lipid profiles, immunity Obesity, insulin resistance, chronic hepatitis Others Ethanol, benzoate, polyamines, microbial antibiotics P2X, P2Y Intestinal barrier, immunity, natural antibiotics Liver disease, C. difficile infections, irritable bowel syndrome Journal of Complementary Therapies in Health 2025: 3(3). 4 of 9 Carreira M., Esteves T., Afonso R., Almeida T. Autism Spectrum Disorder and Gut Health: Contributions of Naturopathy for an Integrative Perspective. doi:10.5281/zenodo.17776899 Analysing the bibliographic proposals on the role of microbial metabolites in the progression of neurodegenerative diseases, Missiego-Beltrán et al. 13 concluded that ShortChain Fatty Acids demonstrated a crucial role in modulating neuroinflammation, preserving the integrity of the blood-brain barrier, and influencing neuronal plasticity and protection. Furthermore, amino acids and their derivatives demonstrated a significant influence on central nervous system function. These microbial metabolites impact the health of the central nervous system by regulating intestinal permeability, modulating immune responses, and directly influencing neuroinflammation and oxidative stress, which are integral to neurodegenerative diseases. Therapeutic strategies, including prebiotics, probiotics, dietary modifications, and faecal microbiota transplantation, confirmed the potential to restore microbial balance and increase the production of neuroprotective metabolites 13. Several recent scientific studies indicate that the composition of the gut microbiota and its metabolites are altered in individuals with ASD 14-18. The metabolism of autistic people is naturally more sensitive than normal, being responsible for the development of several health problems, such as digestive, gastric, allergic, intestinal, neurological, motor, inflammatory, mood alterations, concentration, and social interaction 19. The meta-analysis conducted by Iglesias-Vázquez et al. 17 presented a dysbiotic bacterial profile in children with ASD. They observed that children with ASD, when compared to neurotypical children, showed a higher abundance of Bacteroidetes (Bacteroides and Parabacteroides) and some genera of the Firmicutes class (specifically Clostridium, Faecalibacterium, and Phascolarctobacterium), along with a lower abundance of Coprococcus and Bifidobacteria. The study's conclusions reveal that inflammation and immune system dysfunction, mediated by microbiota composition, are key elements in the development of gastrointestinal problems and other extraintestinal diseases, such as autism itself. However, the direction of causality, whether changes in the microbiota lead to inflammation and immune imbalance, or vice versa, is not yet proven. The results of the recent study by Aziz-Zadeh et al. 20 show that faecal levels of specific tryptophan-related metabolites, including kynurenate, were significantly lower in autistic individuals compared to neurotypicals, and were associated with: changes in insular and cingulate cortical activity previously implicated in ASD ; and the severity and symptoms of ASD (e.g., ADOS scores, disgust proneness, and sensory sensitivities). Furthermore, activity in the mid-insula and mid-cingulate regions significantly mediated the relationships between tryptophan microbial metabolites (indole lactate and tryptophan betaine) and ASD severity and disgust sensitivity. Thus, associations were identified between intestinal microbial metabolites of tryptophan, ASD symptoms, and brain activity in humans, particularly in cerebral regions associated with interoceptive processing. High plasma levels of the gut-derived metabolite trimethylamine N-oxide (TMAO) were associated with ASD and symptom severity 15. Liu et al. 21 studied the causality of ten intestinal metabolites (trimethylamine-N-oxide, betaine, carnitine, choline, glutamate, kynurenine, phenylalanine, serotonin, tryptophan, and tyrosine) in the development of ASD and the results revealed that serotonin may increase the risk of ASD, and that choline could decrease the risk of ASD. Individuals with ASD exhibit various altered levels of metabolites in the blood and urine, many of bacterial origin, such as SCFAs, indoles, and lipopolysaccharides. The lower integrity of the gut-blood barrier in individuals with ASD may explain the leakage of bacterial metabolites into the organism, triggering new physiological responses or metabolic alterations, and the use of specific probiotics can restore intestinal homeostasis 16. The active use of biomarkers to monitor the physiological state of patients with ASD is useful for the diagnosis, intervention, and treatment of the disease 15,16. Considering the relationship between alterations in the abnormal gut microbiota and the behavioural symptoms of individuals with ASD, modification of the intestinal microbiome is a potential pathway for improving gastrointestinal and behavioural symptoms in children with ASD. Journal of Complementary Therapies in Health 2025: 3(3). 5 of 9 Carreira M., Esteves T., Afonso R., Almeida T. Autism Spectrum Disorder and Gut Health: Contributions of Naturopathy for an Integrative Perspective. doi:10.5281/zenodo.17776899 Microbiota Transfer Therapy (MTT), which combines antibiotics, an intestinal cleanse, a stomach acid suppressor, and faecal microbiota transplantation, is reflected in significant improvements in gastrointestinal symptoms, autism-related symptoms, and the gut microbiota. Faecal microbiota transplantation could transform the dysbiotic intestinal microbiome into a healthy one through the transfer of a large number of commensal microorganisms from a healthy donor 14,22. Kang et al. 14 followed 18 participants two years after undergoing MTT treatment and verified a maintenance in most improvements in gastrointestinal symptoms and autism-related symptoms. Important changes in the gut microbiota at the end of the treatment remained at follow-up, including significant increases in bacterial diversity and the relative abundances of Bifidobacteria and Prevotella. They concluded the long-term effectiveness of MTT as an intervention with the potential to treat children with ASD who present with gastrointestinal problems. Nutritional deficiencies and deficient metabolism Healthy eating as a form of autism treatment has been the subject of several studies, and there is evidence that the autistic person has a more sensitive immune, digestive, and intestinal system, and that a diet free of casein, lactose, and others helps maintain their health. These substances produce numerous disorders and discomforts in the organism of an autistic person, as their digestive system is unable to process these more complex proteins, causing a kind of disorder, and triggering problems such as food allergies, behaviour changes, among other issues. These reactions happen because these proteins are longer and more complex chains, which hinders digestion and absorption in the intestine, and they end up being released whole into the bloodstream. Consequently, they develop the same function as a drug, such as morphine, which makes the autistic child not have the same perception of pain as a neurotypical child, and justifying some self-mutilation behaviours 23. Hartman et al. 12 analysed several studies on dietary approaches for the management of ASD, including elimination diets for gluten, casein, or complex carbohydrates, the ketogenic diet, and the low-oxalate diet ; and dietary supplements such as fatty acids, probiotics and prebiotics, vitamins, minerals, glutathione, phytochemicals, and hormones. They concluded that some approaches including a glutenand casein-free diet, supplementation with fatty acids, and the use of pre/probiotics, demonstrated improvements in gastrointestinal and behavioural symptoms associated with ASD. Adıgüzel et al. 24 corroborate the premise that the glutenand casein-free diet, the ketogenic diet, the specific carbohydrate diet, the Feingold diet, and the low-oxalate diet are recommended in autism intervention. They add that dietary supplementation is also recommended to prevent vitamin and mineral deficiencies resulting from the diet and to reduce symptoms. They concluded that diet and some nutrients may play an important role in the management of autism. Other substances, such as colouring agents, can increase hyperactivity symptoms, and when removed from the autistic person's diet, they are able to concentrate more, maintain focus, and feel calmer. With the removal of casein, the autistic person can improve their intestinal and mental system, as it acts as a kind of drug in their organism. The total suspension of lactose contributes to the proper functioning of the digestive and intestinal system, such as the decrease in gas and bloating. Acidic foods are a major inducer of problems for the person who has reflux, such as irritations in the oesophagus and stomach 23. Given that gastrointestinal problems appear to be over-represented in the ASD population, and that these problems have been associated with various behavioural and neurological deficits, dietary manipulation can offer an economical and easily implemented approach to improving the quality of life of people with ASD 12. The neuro-immuno-endocrine relationship in the behavioural modulation of individuals with ASD is evident, making it possible to resort to dietary changes as an auxiliary treatment, improving intestinal symptoms and modulating extraintestinal behaviours 2. Journal of Complementary Therapies in Health 2025: 3(3). 6 of 9 Carreira M., Esteves T., Afonso R., Almeida T. Autism Spectrum Disorder and Gut Health: Contributions of Naturopathy for an Integrative Perspective. doi:10.5281/zenodo.17776899 Inflammation and oxidative stress Oxidative stress is a crucial event underlying several paediatric neurological diseases, such as central nervous system tumours, ASD, and Attention Deficit Hyperactivity Disorder (ADHD). Neuroprotective therapy with natural compounds used as antioxidants has the potential to delay, improve, or prevent various paediatric neurological diseases 25. Many studies demonstrate the role of oxidative stress in the pathological process of ASD, as these patients exhibit higher levels of oxidative stress and lower antioxidant capacity 15. With the development of advanced technologies, such as mass spectrometry, more mechanisms and biomarkers associated with autism have been identified. Many recent studies have demonstrated a link between the development of ASD and increased oxidative stress. Oxidative stress contributes to ASD in several ways, including post-translational protein modifications (e.g., carbonylation), abnormal metabolism (such as lipid peroxidation), and the toxic accumulation of reactive oxygen species. To detect increased oxidative stress in individuals with ASD, various biomarkers have been developed and used. The identification of biomarkers can be used for early diagnosis and evaluation of interventions in ASD, as well as to guide targeted pharmacological or nutritional treatments 21. The neuroprotective effects of quercetin against oxidative stress can be used in the intervention of various neurodegenerative disorders, causing an anti-carcinogenic, antiinflammatory, antiviral, anti-obesity, and antimicrobial effect. Therefore, quercetin appears to be a suitable supplement for therapy against paediatric neurological diseases 25. The pine bark extract is composed of bioflavonoids, catechins, proanthocyanidins, and phenolic acids, acting as a powerful antioxidant, stimulating the activities of some enzymes, such as superoxide dismutase and endothelial nitric oxide synthase, and exhibits other biological changes. Although there are no scientific studies on individuals with ASD, the study by Dvorakova et al. 26 with children with ADHD verified a decrease in total antioxidant status levels, concluding that the administration of pine bark extract normalises total antioxidant status in children with ADHD. Pterostilbene, derived from resveratrol, also possesses numerous physiological activities that promise to be a new therapy for central nervous system disorders, involving mechanisms such as antioxidant and anti-inflammatory activity, regulation of lipid metabolism and vascular smooth muscle cell proliferation, improved synaptic function and neurogenesis, induction of glioma cell cycle arrest, and inhibition of glioma cell migration and invasion. Studies have identified possible molecular targets and pathways for the protective actions of pterostilbene in central nervous system disorders, including the AMPK/STAT3, Akt, NF-κB, MAPK, and ERK signalling pathways 27. This evidence provides solid support for exploring its use in ASD, especially in naturopathic approaches aimed at reducing neuroinflammation and protecting the brain. Sunand et al. 28 analysed the therapeutic role of resveratrol and pterostilbene, alone and in combination, in reversing the behavioural, biochemical, and histopathological changes induced by valproic acid, in a postnatal model of autism with oxidative stress and neuronal injury. They found that resveratrol and pterostilbene proved to be good nutraceuticals in reversing the autism-associated deficits induced by valproic acid. They concluded that resveratrol and pterostilbene, both alone and in combination, possess a strong protective capacity against oxidative stress, behavioural deficits, and VPA-induced cellular neurodegeneration, thanks to their antioxidant, cognition-enhancing, and neuroprotective effects, constituting an effective therapeutic approach to intervene in some challenges associated with autism. 3. Final remarks From the literature review, it was found that individuals with ASD frequently exhibit a dysbiotic gut microbiota profile, associated with alterations in the production of key Journal of Complementary Therapies in Health 2025: 3(3). 7 of 9 Carreira M., Esteves T., Afonso R., Almeida T. Autism Spectrum Disorder and Gut Health: Contributions of Naturopathy for an Integrative Perspective. doi:10.5281/zenodo.17776899 metabolites, such as short-chain fatty acids, tryptophan and choline derivatives, neurotransmitters, and inflammatory compounds, which directly or indirectly influence brain function, behaviour, and the immune system 17. Naturopathy, by recognising the individual as a unique being inseparable from their internal and external environment, proposes a personalised and non-reductionist approach, considering the singularity of the gut microbiota, the impact of lifestyle, diet, exposure to toxins, and the inflammatory and oxidative state of the organism. This approach proves to be especially relevant in the monitoring of people with ASD, by offering intervention strategies adapted to their individual needs, such as the correction of intestinal dysbiosis, the rational use of probiotics, prebiotics, and nutraceuticals with neuroprotective properties (such as pterostilbene and pine bark extract), and the adoption of specific diets (free of gluten, casein, or oxalates). The identification of biomarkers can be used for early diagnosis and evaluation of interventions in ASD, as well as to guide targeted pharmacological or nutritional treatments 4,10. Although it is not possible to attribute a defined pattern of microorganisms in individuals with ASD, a decreased diversity and a greater number of alterations in some individuals were evident. This premise should be considered, as it identifies a set of molecules that can be used as biomarkers, essential for diagnosis, evolution, and treatment effectiveness, but also as a therapeutic intervention, through their modulation via probiotics, prebiotics, faecal microbiota transplantation, antibiotics, and diet, with a good contribution to the relief of the symptomatology felt by these patients 29. Although the mechanisms involved in autism are complex and multifactorial, the data presented suggest that modulating the gut microbiota and strengthening the body's antioxidant defences may contribute to the reduction of neuroinflammation, improvement of intestinal permeability, and optimisation of brain function. The correlation between the gut and the brain—the central axis of naturopathic intervention—thus gains a prominent place in the modern understanding of autism, requiring continuous research and increasingly integrated, individualised, and evidence-based clinical interventions. Most studies on ASD and children's gut microbiota were published in internationally influential and cited journals, indicating that this research has received widespread attention. However, some questions remain unanswered, such as the exact function of the gut microbiota and the mechanism of interaction between the gut microbiota and autism in children. Therefore, these issues need more future research 30, through new clinical trials with individuals as homogeneous as possible, both in age, severity, and type of symptomatology, as well as under identical conditions in all groups 29. Thus, it is concluded that naturopathy, by integrating science, nature, and individuality, offers valid and complementary contributions to the approach of autism, and it is essential to encourage more clinical studies that explore the impact of intestinal modulation and antioxidant support on the health outcomes of people with ASD. Credit author statement: Conceptualization: M.C.; Investigation: M.C.; Writing, reviewing and editing: M.C., T.E., R.A., and T.A. All authors have read and agreed to the published version of the manuscript. Funding: This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Conflict of Interest: The authors declare that there are no conflicts of interest. Institutional Review Board Statement: Not applicable. Informed Consent Statement: Not applicable. Journal of Complementary Therapies in Health 2025: 3(3). 8 of 9 Carreira M., Esteves T., Afonso R., Almeida T. 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