The authors examine the results of the National Survey on Treatment Effectiveness for Autism focusing on nutraceuticals. They investigate the overall benefits and adverse effects of the main vitamins, minerals and other nutritional supplements used in subjects with ASD through the answers in a survey mainly administered to parents of subjects with ASD. I think this topic is relevant within ASD research because complementary and alternative medicine is often overused in subjects with ASD without evidence of efficacy. However, in my opinion, the authors should address some critical issues before the publication.

General comment: in my opinion, it is more appropriate to talk about “perceived benefit” rather than benefit/effective change because each product was evaluated through a survey without a clinical trial or medical examination of the subject after the period of administration. Moreover, in most cases, the surveys were completed by the caregivers of subjects with ASD. Therefore the use of nutraceuticals was evaluated from an external point of view. For example, the sentence “this study suggests that nutraceuticals have clinical benefits and favorable effect profiles” should be changed in that way.

Introduction: the authors provide a detailed background with a broad overview of the literature on this topic. Lines 44-54 I think this paragraph should be shortened since the feeding problems are marginal within the treated topic. Lines 63-67, the authors should better specify what they mean with “some CAM were potentially helpful for treating seizures” based on the cited paper.

Materials and Methods: line 104 what does it mean that “no current diagnosis but was previously on the autism spectrum”? Is it based on a clinical judgment? What was the tool used for assessing autism and autism type? I think it should be specified. Lines 121-123 Why the 20% and 15% thresholds were chosen? It should be specified. Line 126 “for each symptom” is repeated. Lines 129-132, the authors state that “The current ASD severity was subtracted from the severity at baseline (3 years of age) such that a decrease in severity would indicate an improvement” and “it was determined whether the use of the nutraceutical was associated with improvements in ASD symptoms by comparing those who used the nutraceutical to those who did not”. The authors do not consider the subjects' age and how long the subject has taken the specific nutraceutical. These points should be addressed in the study limitations. Lines 138-139 why the used model comprise “number of antibiotic treatments in the first 3 years of life”? This should be specified. Lines 142-144, the authors examined if the use of the nutraceutical was associated with improvements in ASD symptoms by comparing those who used the nutraceutical to those who did not. Did they a preliminary analysis between the two groups to compare the diagnoses at three years? A significantly higher percentage of less severe diagnoses at T0 could be present in one of the groups, possibly representing a bias. In general, a comparison between the characteristics of the two groups (subjects who have used nutraceuticals and subjects who did not) could limit the risk of bias arising from baseline differences between intervention groups.

Results: I think that tables are too much. Please summarize. Alternatively, I suggest inserting some tables in the supplementary materials. Even if table 11 is quite long, it is fascinating for an overview of nutraceuticals. I recommend keeping it in the main text. It can help to guide researchers in choosing the most promising nutritional supplements in future clinical trials.

Discussion: Although the discussion is well structured and convincing, I think it can be summarized, and some parts are more properly to be included in the introduction (for example, lines 380-384). Further considerations on the findings related to adverse events could be useful for clinicians and researchers. The main limitation, as mentioned above, is that adverse events and benefits were assessed through a survey without the support of a clinician/medical examination. In my opinion, this should be clearly stated within the limits of the study.