Natural Supplements For ADHD: Benefits and Side Effects

Using natural supplements to treat attention deficit hyperactivity disorder (ADHD) might help to manage symptoms, with omega-3 fatty acids and certain vitamin and mineral supplements among the most studied. That said, the research evidence to support this use is limited.

Stimulants remain the most common treatment for ADHD, with fewer symptoms in 70% to 80% of children who take them. There is evidence to show that some supplements help people with ADHD who have nutritional deficiencies, though. Vitamin D, magnesium, and other nutrients remain under study for these benefits.

Omega-3 Fatty Acids

Omega-3 fatty acids are essential nutrients that you must get from your diet since your body doesn’t produce them. Dietary sources include fatty fish like salmon and tuna, seeds such as flax and chia, and nuts such as walnuts.

Health Benefits

Research is inconclusive about the efficacy of omega-3 supplements in treating ADHD.

A 2018 systematic review (answering a research question by collecting and summarizing evidence) and meta-analysis (using statistical methods to summarize results) of eight studies involving a total of 628 participants indicated that children and adolescents with ADHD tend to have a deficiency in omega-3 fatty acids.

The review suggested omega-3 supplements improve clinical symptoms and cognitive performance in children and adolescents with ADHD.

A 2017 systematic review of 25 randomized controlled trials (trials in which participants are randomly assigned into one of two groups) showed inconclusive results. It found about half of the studies reported some beneficial effects of omega-3 fatty acids on ADHD symptoms, but the other half reported negative results.

Numerous other studies and reviews have been conducted on the use of omega-3s in treating ADHD, but differences in the studies make them hard to compare. Results from these studies vary.

Overall, it is unclear if omega-3 supplementation is helpful for ADHD symptoms, but it may be worth looking into if the person has a deficiency.

Possible Side Effects

Side effects of omega-3 supplements tend to be mild. They may include:

• Unpleasant taste
• Bad breath
• Bad-smelling sweat
• Headache
• Gastrointestinal symptoms such as heartburn, nausea, and diarrhea

Omega-3 supplements may interact with medications that affect blood clotting.

People with seafood allergies should be cautious taking omega-3s as it is unclear if it is safe for them to take fish oil supplements.

Dosage and Preparation

According to some preliminary research, fish oil supplements may be more beneficial than docosahexaenoic acid (DHA).

Current evidence suggests supplementation with a dose of 1–2 grams of omega-3 daily with a substantial content of eicosapentaenoic acid (EPA) within the omega-3 formulation. 

Check with your healthcare professional before taking omega-3 supplements or giving them to your child, especially if there is a blood clotting disorder or seafood allergy present.

Iron Supplements

Iron is used by the body to make hemoglobin in red blood cells. Hemoglobin transports oxygen to nourish your tissues. Dietary sources include meat (especially red meat), tuna, and dark leafy greens.

Health Benefits

A 2014 study found an association between iron deficiency and ADHD symptoms in children. The study did not conclude that iron deficiency causes ADHD but suggests that it could lead to ADHD symptoms in relationship with genetics, environmental risk factors, absence of iron supplementation, and diet.

A 2013 study indicated that iron deficiency increased the risk of psychiatric disorders, including ADHD.

A 2012 meta-analysis found that people with ADHD tended to have lower iron levels than participants without ADHD. With these results in mind, people with ADHD may wish to be tested for iron deficiency.

Possible Side Effects

Too much iron can be dangerous or even fatal, especially for children.

Side effects of iron supplements can include:

• Upset stomach
• Constipation
• Nausea
• Abdominal pain
• Vomiting
• Fainting

High doses of iron may decrease zinc absorption. Iron supplements can interact with other medications and supplements, as well. Consult with your healthcare provider or pharmacist about possible interactions.

Dosage and Preparation

The dosage for iron supplements depends on factors such as age, sex, how deficient the person is, and other considerations.

The maximum amount of iron daily from all sources, including food and supplements, is as follows:

• Birth to 13 years: 40 milligrams
• 14 years and over: 45 milligrams

Magnesium

Magnesium is a dietary mineral found in foods like leafy greens, nuts and seeds, whole grains, and beans and legumes.

People with ADHD may have low levels of magnesium. Magnesium has many important functions in the body, including regulating blood pressure and nerve and muscle function.

Magnesium has been studied for its ability to calm anxiety, but research results are mixed. Some people believe that magnesium may also help improve hyperactivity symptoms in people with ADHD.

Health Benefits

A small study of 20 participants found magnesium deficiencies in children with ADHD. The study determined that this deficiency correlated with hyperactivity, inattention, and impulsivity. A 2019 meta-analysis also concluded that there is a relationship between magnesium deficiency and ADHD.

A small study from 2015 found that magnesium supplementation could help improve cognitive function in children with ADHD. 

A 2017 review study, however, noted that there has been very little research into the effect of magnesium supplementation on ADHD symptoms, and many of the existing studies are small or poorly designed. Larger, well-designed studies are needed before magnesium supplementation can be recommended for treating ADHD symptoms.

Possible Side Effects

Side effects of magnesium supplements include:

• Diarrhea
• Nausea
• Abdominal cramping

Very high doses of magnesium may cause magnesium toxicity, which is serious and can be fatal.

Dosage and Preparation

The amount of magnesium to take is highly variable depending on the person.

Talk to your healthcare provider to determine if you or your child needs magnesium supplements, and what dosage to take.

Zinc

Zinc is an important mineral found in certain kinds of seafood, red meat, poultry, and dairy products. You can also get dietary zinc from whole grains, beans, nuts, and fortified cereal. There is some evidence that children with ADHD may be deficient in zinc.

Health Benefits

The same small study that found a link between magnesium deficiencies and ADHD symptoms also found that children with ADHD tended to be deficient in zinc. Zinc deficiency also correlated with hyperactivity, inattention, and impulsivity.

There is some limited evidence that zinc supplements might improve certain ADHD symptoms. A small study published in 2020 found that children taking the stimulant medication methylphenidate with a zinc supplement had better attention scores than those taking methylphenidate alone.

More research is needed, however, before zinc supplementation can be recommended for people with ADHD.

Possible Side Effects

Too much zinc can cause side effects such as:

• Nausea
• Vomiting
• Loss of appetite
• Stomach cramps
• Diarrhea
• Headaches

Zinc can interact with other medications and supplements. Consult your healthcare professional and pharmacist before use.

Dosage and Preparation

The amount of zinc to take is highly variable depending on the person.

Talk to your healthcare provider to determine if you or your child needs zinc supplements, and what dosage to take.

Vitamins

Vitamins have not been conclusively shown to directly affect ADHD, but they can correct deficiencies that may be associated with ADHD symptoms.

A 2018 study indicated the possibility that low levels of certain vitamins may contribute to ADHD symptoms. The study specifically looked at 8 vitamins including A, B2, B3, B6, B9, B12, vitamin D, and vitamin E. 

The research found that people with ADHD tended to have lower levels of vitamins B2, B6, and B9 and that B2 and B6 levels correlated with worsened ADHD symptoms. They also found that ADHD might be associated with low levels of vitamin D. However, the authors also noted that other factors like smoking can influence vitamin levels, so more research is needed.

Melatonin

Melatonin is a hormone secreted primarily by the pineal gland (located deep in the brain). It regulates your sleep-wake cycles.

Health Benefits

People with ADHD commonly experience problems with sleep. The medications used to treat ADHD can also affect sleep.

Melatonin taken by children and adults with primary sleep disorders has been shown to:

• Decrease sleep latency (how long it takes to fall asleep)
• Increase total sleep time
• Improve sleep quality

While melatonin hasn’t been shown to improve ADHD symptoms directly, it can help people with ADHD improve their sleep.

Possible Side Effects

Melatonin is considered safe for short-term use, but there are no studies to determine safety for long-term use. No significant side effects of melatonin use in children have been reported.

Side effects of melatonin are uncommon but can include:

• Drowsiness
• Headache
• Dizziness
• Nausea

Dosage and Preparation

Typically, 3–6 milligrams (depending on the child’s weight) of melatonin is taken about a half an hour before bedtime.

St. John’s Wort

The herb St. John’s wort is a flowering herb native to Europe. It is sometimes recommended for treating ADHD, but there is very little evidence to support its use. 

Health Benefits

St. John’s wort has been best studied for its effectiveness in treating depression. It is believed to inhibit reuptake of the neurotransmitters serotonin, norepinephrine, and dopamine.

In people with ADHD, it may work in a similar way to the non-stimulant medication Strattera (atomoxetine) and the antidepressant Wellbutrin (bupropion), which are sometimes prescribed to treat ADHD.

However, so far the evidence has failed to show that St. John’s wort is better than a placebo for treating ADHD symptoms.

Possible Side Effects

St. John’s wort could interact with certain ADHD medications, putting you at greater risk for serotonin syndrome, a rare but dangerous complication.

Other side effects may include:

• Sensitivity to sunlight
• Anxiety
• Dizziness
• Dry mouth
• Sleeplessness
• Headache
• Nausea
• Sexual dysfunction

Dosage and Preparation

A typical dose of St. John’s wort is 300 mg three times daily. Take with meals. 

Gingko Biloba

Ginkgo biloba is the extract of a tree that grows in China. It is rich in antioxidants and is thought by some to improve symptoms in people with ADHD. The research into its effectiveness, however, is limited. 

Health Benefits

One 2014 study looked at the effect of a Ginkgo biloba extract in 20 children with ADHD over a three- to five-week period. The authors reported “possible improvements” in ADHD symptoms and overall quality of life, but they also noted that more research is needed. 

Possible Side Effects

When taken as directed, Ginkgo biloba is likely safe. Reported side effects are mild and may include:

• Nausea
• Headache
• Dizziness
• Rash

Larger doses may cause vomiting and diarrhea.

Ginkgo biloba may act as a blood thinner, so if you have a bleeding disorder or are taking a blood thinner such as warfarin or aspirin, you should avoid taking Gingko biloba. Interactions with other drugs haven’t been well-studied, so ask your healthcare provider before you start taking Ginkgo biloba.

Dosage and Preparation

A typical dose of Ginkgo biloba is 120 to 240 mg per day.

Ginseng

Ginseng is a plant native to eastern Asia and North America. It has been studied in combination with omega-3 fatty acid in children with ADHD.

Health Benefits

A small study published in 2020 found that children taking a combination of 3 mg of Korean red ginseng extract and 500 mg of omega-3 had improvements in ADHD symptoms and cognitive function including attention, memory, and executive function.

However, it’s not clear how much of a role ginseng played in the reported improvements. The authors also noted that larger studies are needed to confirm the results.

Possible Side Effects

Ginseng is thought to be safe for short-term use. It is usually well-tolerated, but side effects can occur. These are typically mild and include:

Ginseng is not safe to take during pregnancy. A chemical found in Panax ginseng has been associated with birth defects. 

Because ginseng contains chemicals that act like estrogen in the body, you should also avoid ginseng if you have a hormone-sensitive condition such as breast cancer or endometriosis. Ginseng may also affect blood sugar levels.

Do not take ginseng if you are taking a blood thinner such as warfarin. Ginseng may also interact with MAOIs, diabetes medication, and immunosuppressants. Always consult your healthcare provider before taking a new supplement.

Dosage and Preparation

A typical dose of ginseng can range from 100 mg daily to 3,000 mg daily. Do not take ginseng for longer than 12 weeks. Higher doses are more likely to cause side effects.

What to Look For

So many CAM treatments are suggested for ADHD that it can be hard to separate fact from fiction.

The organization Children and Adults with Attention-Deficit/Hyperactivity Disorder (CHADD) offers some advice for vetting these options.

Ask yourself:

• Have clinical trials been conducted to prove this treatment works?
• Is information about this treatment available from a trusted source?
• Is there a respected national organization of people who practice this therapy?
• Does the person administering the treatment need a state license?
• Does my health insurance cover this treatment? (Insurance carriers usually won’t cover unproven treatments.)

CHADD suggests some red flags to look for that indicate the treatment is suspicious and should be avoided, including if:

• They claim that the treatment works for everyone with ADHD, even though no single treatment is effective for everyone.
• There is a lack of credible research and studies and only anecdotal evidence (derived from stories people tell).
• No directions are given for using it properly or the contents are not listed on medication containers
• There is no information about side effects.
• They claim that the product is natural without acknowledging that “natural” does not necessarily mean safe.
• There are bold claims such as the treatment is “a secret formula,” “astonishing,” “miraculous,” “an amazing breakthrough” or a “cure.”
• You learn about it through infomercials or a book an author is trying to sell.
• The “medication” comes by mail order instead of through a healthcare professional.
• They claim that doctors unfairly talk down the treatment or won’t tell the public about it.

Summary

Stimulant medications are the treatment most supported by evidence in the treatment of ADHD, but other treatments are sometimes suggested. While dietary supplements may not help ADHD symptoms on their own, they can help manage deficiencies that affect ADHD symptoms.

Certain herbs have also been studied for use in people with ADHD, but there is limited evidence that they work. Current research does not support the use of supplements as a stand-alone alternative to medication and/or behavioral therapy for ADHD.

Before starting any treatment for ADHD, talk to your healthcare professional. It is important to determine if there are any deficiencies in you or your child before treating with supplements.