Ayahuasca and Public Health II: Health Status in a Large Sample of Ayahuasca-Ceremony Participants in the Netherlands

Ayahuasca is a traditional Amazonian plant decoction typically combining a β-carboline–containing vine (Banisteriopsis caapi) with DMT-containing plants, and its ritual use has spread internationally. Previous clinical, experimental and observational work indicates a generally favourable acute safety and tolerability profile in controlled settings, low risk of abuse, and potential benefits for mood, substance-related disorders and overall well-being, but globalisation of ceremonial use raises public‑health and policy questions. In Europe, and specifically in the Netherlands, legal controversy around sacral use (for example the Santo Daime church case) has created a policy environment at odds with some scientific evidence, and no large-scale evaluation of regular ceremony participants' health had been conducted in the Netherlands prior to this study. Kohek and colleagues set out to assess the health status of regular ayahuasca‑ceremony participants in the Netherlands using a broad questionnaire of validated and standardised health indicators. The study aimed to compare participants' general and lifestyle‑related health measures with normative Dutch data and to explore coping strategies and value engagement among attendees, with the stated goal of providing data useful for evidence‑based public policy decisions.

The study recruited participants via an existing network of ayahuasca facilitators in the Netherlands; facilitators were asked to invite members of their networks to take part. Inclusion criteria were age 18 or older and first participation in an ayahuasca ceremony at least six months before assessment. The extracted text reports a final sample of 377 participants. Data collection was conducted online (approximately 30 minutes per respondent), and procedures were approved by the Leiden University research ethics committee. The authors developed a questionnaire from standard instruments and national surveys. Core domains included general health (self‑rated health, chronic disease, health‑service contacts, blood pressure, cholesterol, diabetes), mental health screening items, medication use, tobacco/alcohol/other substance use, physical activity (work, transport, leisure), dietary habits (items from the Dutch National Food Consumption Survey), social support, demographic and socioeconomic data, COVID‑19 impact questions, and ayahuasca‑specific items (e.g. number and setting of ceremonies, brew type, subjective effects). Height and weight were self‑reported for BMI calculation. The Engaged Living Scale (ELS; valued living and life fulfilment subscales) and the COPEeasy coping questionnaire (active problem‑focused, avoidant, support‑seeking and several subdomains) were included. Statistical analysis began with descriptive statistics. A multivariate general linear model (GLM) tested associations between the number of ceremonies attended (factor) and 17 dependent variables, with Bonferroni post‑hoc tests; analyses adjusted for age, gender, urban/rural environment, marital status and education. A linear regression identified predictors of subjective health status from 14 candidate variables. One‑way ANCOVA assessed differences in coping, ELS subscales, health status and related variables across ceremony types (religious, Indigenous, neoshamanic) and across experience levels, with age adjustment where noted. The authors applied multiple‑comparison corrections and report that they treated p < .001 as the threshold in many comparisons; Cohen's d effect sizes are reported where possible. IBM SPSS v22 was used.

Sample characteristics: 377 respondents met inclusion criteria. The mean age was 48.8 years (SD = 11.6), 50.1% were women, and 84.6% were Dutch nationals. More than half lived in urban areas (52.3%); 58.9% owned their home and 54.1% were partnered or married. Educational attainment was high (75.9% had a university degree) and 82.7% were employed or self‑employed. Patterns of ayahuasca use: 57.8% began using ayahuasca more than five years earlier. Fifty‑five per cent had participated in a ceremony within six months before the survey. Thirty per cent reported participating more than 100 times. Ceremony context was mainly Santo Daime (40.3%) or neoshamanic local practitioners (40.6%). The most commonly reported brew was Banisteriopsis caapi plus Psychotria viridis (63.9%); 6.4% drank ayahuasca analogues and 5% drank both. When asked about effects on life, 99.8% indicated a positive influence. Sixty‑four per cent reported physical benefits (for example improved general health, pain management or increased energy). Twenty‑four per cent reported prior substance‑related problems, 2.4% a current substance problem, and 53% reported decreased substance use following ayahuasca exposure. Adverse events were uncommon (8.5% reported experiencing or witnessing events), most often acute panic/anxiety, fainting or difficult journeys; prolonged effects were rare. General health and lifestyle: A large majority (94.7%) reported good or very good perceived health. Normal BMI (18.5–25 kg/m2) was observed in 72.6% of participants versus 48.8% in normative Dutch data. The sample had lower prevalence of chronic diseases, hypertension, high cholesterol and diabetes compared with national norms. Participants reported fewer contacts with medical specialists in the prior year but more visits to physiotherapists, psychologists and psychiatrists. Mental‑health screening items showed most respondents felt happy (71.3%), calm (75.3%) and energetic (67.4%), while small percentages reported feeling down (9%), nervous (8.5%) or depressed (5.8%). Prescribed medicine use was lower than population norms, whereas use of herbal and other non‑prescription remedies was higher. Substance use: Compared with normative Dutch data, the sample did not differ for tobacco, alcohol, laughing gas, or heroin but reported higher use of cannabis, psilocybin mushrooms/truffles, MDMA/ecstasy and LSD. The questionnaire captured smoked tobacco only; the authors note rapé (tobacco snuff) use in ceremonies may have been under‑detected. The health indicators did not reveal increased drug‑related harms in this sample. Predictors of subjective health: In a linear regression, greater presence of long‑term diseases, higher prescribed medicine use and greater feelings of loneliness predicted poorer self‑reported health (reported F statistic F(14)=9.59 with associated p values: long‑term diseases p < .001; prescribed medicines p = .01; loneliness p < .001). Higher scores on the ELS life fulfilment subscale predicted better subjective health (p = .003). Physical activity and diet: Seventy‑four per cent met Dutch exercise guidelines (≥150 minutes moderate exercise per week). Dietary patterns showed higher consumption of vegetables, legumes and fruits (including nuts and seeds) and lower consumption of grains and meat compared with national averages. Coping and values: After applying Bonferroni correction (authors emphasise p < .001 as the threshold), several non‑significant tendencies emerged: those with >100 ceremonies tended to report more active problem‑focused coping than 3–10 or 10–20 attendance groups, and less avoidant coping than the 3–10 group. Significant differences at the corrected threshold included higher ELS valued living scores and higher total ELS scores for participants with >100 ceremonies compared with those with 3–10 ceremonies (p < .001; Cohen's d ≈ .60–.62). Ceremony context comparisons showed a tendency for religious ceremony attendees to use more active problem‑solving than Indigenous‑ceremony attendees (p = .009), but this did not meet the stricter corrected threshold in all reported comparisons. COVID‑19 impact: Seventy per cent reported little or no pandemic influence; among the 29.2% reporting moderate to extreme impact, 82.4% reported negative effects. Since the pandemic began, 30.5% reported more stress, 22.5% more anxiety and 33.7% more sadness. Most participants reported no major changes in tobacco, alcohol or other substance use. A GLM found one difference in alcohol use: those with >100 ceremonies reported less alcohol use since the pandemic compared with those with 3–10 ceremonies (F(4)=2.48; p = .04), while no other pandemic‑related differences were observed.

Kohek and colleagues interpret the results as showing that long‑term participants in ayahuasca ceremonies report better general well‑being, fewer chronic and lifestyle‑related diseases, higher physical activity and a diet more aligned with national guidelines, relative to Dutch normative data. They note these findings are consistent with prior studies of ceremony participants and with broader hypotheses that classic hallucinogens may encourage healthful behaviours and lower odds of some lifestyle diseases. The authors also discuss substance use patterns: although the sample reported higher use of certain illicit drugs typical of psychedelic‑using populations (cannabis, psilocybin, MDMA, LSD), the survey did not show elevated drug‑related harms compared with the general population. Regression results linking life fulfilment with better subjective health and loneliness with poorer health are highlighted; the authors situate loneliness as an important risk factor for mental and physical health. Experience‑related differences—more experienced participants scoring higher on value engagement and more active coping—are reported, with adjustment for age noted and the possibility that either repeated ceremony participation shapes values or pre‑existing traits select for continued attendance. The authors acknowledge several limitations. The sample consisted of volunteers with generally positive attitudes to ayahuasca, potentially excluding people who discontinued use because of adverse outcomes. The cross‑sectional, retrospective and observational design prevents causal inference and dose‑ or brew‑specific effects could not be assessed. Religion and other confounders may explain some associations. The investigators caution that while biological, neurocognitive and psychological mechanisms have been proposed to account for beneficial effects, the present data cannot establish causation. Finally, they raise a policy concern: the Dutch court ruling restricting sacramental ayahuasca use may push ceremonies underground, which could be detrimental to public health. The authors recommend policymakers rely on scientific evidence when forming public‑health decisions regarding ayahuasca.