ADHD: Evidence-Based Supplement Guide

Eleven of the 72 people in Avelor with a saved stack hold something taken for attention or focus. Before anything else: **nothing in this guide is a reason to change, reduce, or stop an ADHD medicine.** That decision belongs to the clinician who prescribes it, and a supplement appearing to help is not evidence that a medicine can be lowered. The guide exists to describe what the research supports alongside treatment, not instead of it. The single most useful finding in this literature is about who does the rating, not about any compound. A systematic review pooled randomised trials of dietary and psychological treatments for ADHD and analysed them twice (PMID 23360949). When outcomes came from raters closest to the treatment, every dietary and psychological approach produced a statistically significant effect. When the best probably-blinded assessment was used instead, only free fatty acid supplementation and artificial food colour exclusion stayed significant, and the rest fell away. That gap is the reason this category is full of confident claims. It also tells you where you are standing: you are the rater closest to your own treatment, which is the position the effects came from and the position they did not survive. What survives blinded assessment is modest and narrow. Free fatty acid supplementation kept a small significant effect in that analysis (PMID 23360949), consistent with an earlier meta-analysis of omega-3 supplementation for ADHD symptoms (PMID 21961774). Artificial food colour exclusion kept a larger effect, but often in participants selected for food sensitivities, which is a narrower group than the label implies (PMID 23360949). Broader reviews of diet interventions reach compatible conclusions (PMID 32513046, 37505402). A placebo-controlled trial of a broad micronutrient formula in children met one of its two primary outcomes and missed the other. Blinded clinician rating favoured micronutrients. The parent-rated symptom composite did not separate from placebo (PMID 34303786). A companion analysis examined gut microbiome changes in the same study (PMID 39963956). A clinician guideline for nutraceuticals in psychiatry covers this territory formally (PMID 35311615). Three commonly taken things deserve a specific correction. Iron supplementation in non-anaemic people has a meta-analysis reporting improvements in anxiety, fatigue, cognition and short-term memory, and **no improvement in attention**, with the effects absent once iron-deficient participants were excluded (PMID 40945632). A separate systematic review covers iron and zinc trials in ADHD specifically (PMID 34836314). Magnesium's meta-analysis is about **status, not treatment**. It pooled observational studies comparing serum magnesium between people with and without ADHD, with very high heterogeneity. It does not test whether supplementing changes symptoms (PMID 30807974). For comparison, the interventions with the strongest evidence in ADHD are the medicines and the psychological treatments. Systematic reviews cover them in children and adolescents (PMID 38523592), in adults (PMID 39701638), and for quality of life specifically (PMID 38823477). Exercise has its own network meta-analysis (PMID 37033046).

1. **Keep taking your medicine as prescribed.** Nothing below changes that, and any change is a conversation with your prescriber. 2. **Know which rater you are.** You sit in the position closest to the treatment, where every approach looked significant before blinding removed most of it (PMID 23360949). 3. **Treat sleep and exercise as part of the plan, not as alternatives to it.** Exercise has a network meta-analysis in ADHD (PMID 37033046) and a broader umbrella review for executive function (PMID 40049759). 4. **If you are considering a supplement, omega-3 has the most survivable evidence** (PMID 23360949, 21961774). It is a small effect, and the guide says so rather than rounding it up. 5. **Ask about iron only if there is a reason to**, such as heavy periods or a known low result, and ask the person who can order the test rather than guessing (PMID 40945632).

Where the research supports a timeframe, the micronutrient trial ran over **eight weeks** (PMID 34303786). The dietary trials pooled in the blinded-assessment review varied widely and the review does not report a single duration, which is part of why its pooled estimates carry wide uncertainty (PMID 23360949). The exercise network meta-analysis compared programmes rather than establishing how long any one of them takes to work (PMID 37033046).

- **Most of this evidence is in children, and most people using Avelor are adults.** The blinded-assessment review, the micronutrient trial, and the iron and zinc review are all paediatric or largely paediatric (PMID 23360949, 34303786, 34836314). The adult evidence base is mostly about medicines and psychological treatment (PMID 39701638). - **A status finding is not a treatment finding.** The magnesium meta-analysis compares blood levels between groups and does not test supplementation (PMID 30807974). A difference in average level does not establish that raising it helps. - **Iron improved several things and did not improve attention** (PMID 40945632). That is a specific negative on the exact outcome people take it for, and it is stated rather than softened. - **Artificial food colour exclusion worked best in people selected for sensitivity to them** (PMID 23360949). Generalising that to everyone is the error the review's own wording guards against. - **The micronutrient trial split its primary outcomes** (PMID 34303786). Reporting only the favourable one would be the easiest way to misrepresent this guide's strongest supplement trial. - **My searches repeatedly returned autism literature for ADHD queries.** Those papers were excluded rather than cited, because a paper about autism is not evidence about ADHD even when both appear in the same review.

- **Do not change, reduce, skip, or stop an ADHD medicine because a supplement seems to be helping.** If you want to change anything about your medication, that is a conversation with **the clinician who prescribes it**. This guide takes no position on any medicine's dose or schedule. - **Stimulant medicines and caffeine act on overlapping systems.** A randomised trial compared methylphenidate, modafinil and caffeine as cognitive enhancers (PMID 33201262). If you drink coffee or take a caffeinated pre-workout alongside a stimulant medicine, mention it to **your prescriber**, because it is relevant to how you feel and to what gets attributed to the medicine. - **Urinary pH affects how amphetamine is eliminated** (PMID 25157). Products that change urine acidity, including some vitamin C preparations, are therefore worth mentioning to **the clinician who prescribes an amphetamine-based medicine**. Raise it with them rather than adjusting anything yourself. - **Atomoxetine and several other ADHD medicines are metabolised by pathways that herbal products can change.** Anyone adding a herbal supplement should raise it with **a pharmacist or their prescriber** (PMID 24259638). - **Sleep problems are common alongside ADHD and are not solved by a focus supplement** (PMID 27416139). Persistent sleep difficulty is a reason to see **a clinician**, including because it can look like worsening ADHD. - **New or worsening low mood, anxiety, or thoughts of self-harm are a reason to contact a clinician promptly**, not a reason to adjust a supplement stack.

Resolving to an entity and being interaction-checkable are different things. The interaction catalogue keys on a collapsed name string rather than an entity id, so an entity can exist and still be checked against nothing. Resolves **and** has a catalogue key, so it can be interaction-checked: - `avelor:sup:omega-3`, `avelor:sup:omega-3-fish-oil` Resolves but has **no catalogue key**, so it displays as recognised and is checked against nothing: - `avelor:sup:magnesium-l-threonate` - `avelor:sup:multivitamin` - `avelor:sup:omega-3-fatty-acids` No supplement entity at all, and none is invented here: - **Iron** has no supplement entity, despite being the single most commonly suggested blood test in this area and the subject of the clearest negative finding in the guide. - **Zinc** has no supplement entity. This is the second guide blocked by its absence, after immune. - **Caffeine** has no supplement entity. This is the third guide blocked by its absence, after sleep and athletic, and here it sits next to a stimulant-medicine caution. - **L-theanine** has no supplement entity, despite being one of the most commonly sold focus products. This is the worst pairing of exposure and coverage in any guide so far. The two cautions most likely to matter to a reader on medication involve caffeine and vitamin C, and neither has a supplement entity. Neither can be surfaced by the interaction checker when a user saves a stack. The only fully checkable item here is the one supplement whose measured effect is small.

| PMID | Title | | --- | --- | | 23360949 | "Nonpharmacological interventions for ADHD: systematic review and meta-analyses of randomized controlled trials of dietary and psychological treatments" | | 21961774 | "Omega-3 fatty acid supplementation for the treatment of children with attention-deficit/hyperactivity disorder symptomatology: systematic review and meta-analysis" | | 32513046 | "The use of diet interventions to treat symptoms of ADHD in children and adolescents - a systematic review of randomized controlled trials" | | 37505402 | "Nutrition in the Management of ADHD: A Review of Recent Research" | | 34303786 | "Micronutrients for Attention-Deficit/Hyperactivity Disorder in Youths: A Placebo-Controlled Randomized Clinical Trial" | | 39963956 | "Gut microbiome changes with micronutrient supplementation in children with attention-deficit/hyperactivity disorder: the MADDY study" | | 35311615 | "Clinician guidelines for the treatment of psychiatric disorders with nutraceuticals and phytoceuticals: The World Federation of Societies of Biological Psychiatry (WFSBP) and Canadian Network for Mood and Anxiety Treatments (CANMAT) Taskforce" | | 40945632 | "Psychiatric and cognitive outcomes of iron supplementation in non-anemic children, adolescents, and menstruating adults: A meta-analysis and systematic review" | | 34836314 | "The Role of Iron and Zinc in the Treatment of ADHD among Children and Adolescents: A Systematic Review of Randomized Clinical Trials" | | 30807974 | "Magnesium status and attention deficit hyperactivity disorder (ADHD): A meta-analysis" | | 38523592 | "Treatments for ADHD in Children and Adolescents: A Systematic Review" | | 39701638 | "Comparative efficacy and acceptability of pharmacological, psychological, and neurostimulatory interventions for ADHD in adults: a systematic review and component network meta-analysis" | | 38823477 | "Systematic Review and Meta-Analysis: Effects of Pharmacological Treatment for Attention-Deficit/Hyperactivity Disorder on Quality of Life" | | 37033046 | "Comparative effectiveness of various physical exercise interventions on executive functions and related symptoms in children and adolescents with attention deficit hyperactivity disorder: A systematic review and network meta-analysis" | | 40049759 | "Effectiveness of exercise for improving cognition, memory and executive function: a systematic umbrella review and meta-meta-analysis" | | 27416139 | "Sleep and mental disorders: A meta-analysis of polysomnographic research" | | 33201262 | "Cognitive enhancement effects of stimulants: a randomized controlled trial testing methylphenidate, modafinil, and caffeine" | | 25157 | "Kinetics, salivary excretion of amphetamine isomers, and effect of urinary pH" | | 24259638 | "A review of the pathophysiology, etiology, and treatment of attention-deficit hyperactivity disorder (ADHD)" |