A 2014 trial on vitamins and adult ADHD tested a broad vitamin-mineral formula, not single vitamins or everyday multivitamins (Rucklidge, 2014). In 80 medication-free people with ADHD, self and observer ratings improved more than on a dummy pill. Clinicians' overall impression agreed; their symptom scale didn't. The authors call it preliminary. A 2010 study had no comparison group (Rucklidge, 2010). If you're thinking about a supplement, talk to a clinician first, since some can interact with medication.
Vitamins and adult ADHD: what did the 2014 formula trial find?
A randomized trial published in 2014, with people recruited in New Zealand, assigned participants by chance to one group or the other (Rucklidge, 2014). It was double-blind, so neither the participants nor the researchers knew who was getting what. One group took a broad vitamin-mineral formula for 8 weeks. The other took a dummy pill.
Here's who was studied: 80 people with ADHD aged 16 and over, 7 of them under 18, all recruited from one region of New Zealand. None of them had taken ADHD medication in the 4 weeks before they joined. More than half, 56%, had another condition alongside ADHD.
The results depended on who was doing the rating. When people rated their own ADHD symptoms, the formula group improved more than the dummy-pill group, by a moderate margin that was unlikely to be down to chance. Ratings from an observer showed a similar, moderate difference. But when clinicians rated ADHD symptoms on a standard symptom scale, there was no clear difference between the groups. The gap was small and could easily have been chance.
Clinicians' overall impression of improvement told a different story. They judged 20 of the 42 people on the formula (47.6%) as much or very much improved, compared with 8 of the 38 on the dummy pill (21.1%). Separately, 27 people on the formula (64.3%) and 14 on the dummy pill (36.8%) had a drop of 30% or more on at least one part of the ADHD symptom rating scales used in the trial.
The authors describe all of this as preliminary evidence. They point out that the findings weren't consistent from one type of rater to another, and they say larger trials are needed to confirm them.
What the 2010 study adds, and what it can't
An earlier, smaller study tested a broad vitamin-mineral formula with 36 ingredients in adults with ADHD (Rucklidge, 2010). It was led by the same researcher as a later 2014 trial, in which 80 people with ADHD were randomly given a broad formula or a dummy pill (Rucklidge, 2014). Its design, below, makes it background rather than a second piece of equal evidence.
Who was studied matters a lot here. The results come from 14 adults aged 18 to 55 who finished the study, 9 men and 5 women. They were chosen because they had ADHD plus severe mood swings, and the authors say it's unknown whether the results apply to people with ADHD alone. They referred themselves, and the authors describe them as a motivated group. None were taking ADHD medication.
The design was open-label. Everyone knew they were taking the formula, and there was no comparison group at all. That matters, because the changes could come from expecting to improve, from taking part in a study, or from symptoms easing on their own. The authors say plainly that the changes can't be confidently put down to the formula, and that the study doesn't establish that the formula works.
On ADHD symptoms, the picture was uneven. In this study with no comparison group, average scores for hyperactivity and impulsivity came down into the normal range over the 8 weeks. Attention scores didn't. At the end of the study they were still in the range seen in people with clinical attention problems, and only 4 of the 14 had a drop of 30% or more in inattention scores.
The authors note there was only a 2-month follow-up. Taken with its design, it's best read as background to the 2014 trial, not as a result to weigh on its own.
What the 2014 and 2010 formula studies can't tell you
The 2014 trial (Rucklidge, 2014) and the earlier 2010 study (Rucklidge, 2010) each tested a broad, multi-ingredient vitamin-mineral formula. A result about a broad formula isn't a result about a single vitamin or an everyday multivitamin. Each result belongs to the formula that study used, not to any other product.
The 2014 trial lasted 8 weeks, so it says nothing about longer use. Everyone came from one region of New Zealand, and more than half had another condition alongside ADHD. The authors say both of those limit how far the results can be applied. Everyone in it was off ADHD medication, so the findings describe that group of people only.
Anything a trial didn't measure is an open question, not a settled no. That cuts both ways: a gap in the evidence isn't proof a formula fails, and it isn't proof it helps. For now, what's known doesn't support a specific step for you to take. There's also research on food and ADHD in children, and more on food, nutrition and ADHD in the nutrition section.
Try this today: if you already take any vitamin or supplement, write down the ingredient list exactly as it's printed on the label, plus the date you started, so it's ready for your next appointment.
To sum up the limits: the 2014 trial of 80 people with ADHD, all from one region of New Zealand, found mixed results across raters, lasted 8 weeks and was called preliminary by its own authors, who said larger trials were needed. The 2010 study had 14 people who finished it, all adults with ADHD and severe mood swings who referred themselves, and no comparison group, and its own authors say the changes can't be confidently put down to the formula. If you're thinking about vitamins or supplements, talk to a clinician about your own situation.