3. Unsaturated fatty acids in ADHD¶
3.1. Monounsaturated fatty acids¶
A large study of 432 children found significantly lower serum levels of monounsaturated fatty acids (PUFAs) in children with ADHD. This correlated with an increased intake of nutrient-poor foods such as high-sugar and high-fat foods and a reduced intake of vegetables, fruit and protein-rich foods compared to healthy children.
It remains to be seen whether the change in diet is the cause, consequence or vicious circle of ADHD.
3.2. Polyunsaturated fatty acids (PUFAs)¶
One review came to the recommendation of a combination of EPA, DHA and GLA in a ratio of 9:3:1 for ADHD. The lead author is involved in a company that sells unsaturated fatty acids.
3.2.1. Omega-3 fatty acids¶
An administration of 635 mg eicosapentaenoic acid (EPA) and 195 mg docosahexaenoic acid (DHA) (unsaturated fatty acids) reduced serum CRP and IL-6 levels in children with ADHD and improved ADHD symptoms within 8 weeks in a double-blind placebo study.
A combination of the triple unsaturated fatty acids EPA and DHA in rats in stress tests
- Prevented or compensated dendritic atrophy in the CA3 region of the hippocampus
- Restored GABA release in the CA1 region of the hippocampus
- Improved spatial memory.
A placebo-controlled double-blind study found improvements in attention in children with ADHD as well as in children not affected by omega-3 fatty acids.
A study of healthy adolescents found a trend towards an improvement in sustained attention and ADHD symptoms in those participants who consumed nuts more consistently when consuming walnuts over 6 months. This could reflect the fact that young people who perceive a benefit (even unconsciously) from consuming nuts are more likely to continue doing so.
One RCT found no improvement in ADHD-RS intention score or inattention with omega-3/6 supplementation at either 6 or 12 months. There was a positive response of 46.3% in the omega-3/6 group and 45.6% in the placebo group. The study used two capsules per day, each containing 279 mg eicosapentaenoic acid [EPA], 87 mg docosahexaenoic acid [DHA], 30 mg gamma-linolenic acid [GLA].
Omega-3 fatty acids are among others:
- Eicosapentaenoic acid (EPA)
- A Japanese study found significantly reduced EPA blood plasma levels in 24 people with ADHD under the age of 20.
- Docosahexaenoic acid (DHA)
- A Japanese study found significantly reduced DHA blood plasma levels in 24 people with ADHD under the age of 20.
- A combination of the triple unsaturated fatty acids EPA and DHA in rats in stress tests
- Prevented or compensated dendritic atrophy in the hippocampus CA3 region
- Restored GABA release in the hippocampus CA1 region
- Improved spatial memory.
- Roughanic acid
- Alpha-linolenic acid
- Stearidonic acid
- Eicosatetraenoic acid
- Heneicosapentaenoic acid
- Docosapentaenoic acid
- Tetracosapentaenoic acid
(scoliodonic acid)
- Tetracosahexaenoic acid
(nisic acid)
3.2.2. Omega-6 fatty acids¶
One RCT found no improvement in ADHD-RS intention score or inattention with omega-3/6 supplementation at either 6 or 12 months. There was a positive response of 46.3% in the omega-3/6 group and 45.6% in the placebo group. The study used two capsules per day, each containing 279 mg eicosapentaenoic acid [EPA], 87 mg docosahexaenoic acid [DHA], 30 mg gamma-linolenic acid [GLA].
Omega-6 fatty acids are among others:
- Arachidonic acid (AA)
- A Japanese study found significantly reduced AA blood plasma levels in 24 people with ADHD under the age of 20.
- Linoleic acid (LA)
- Gamma-linolenic acid (GLA)
- Dihomo-gamma-linolenic acid (DHGLA)
4. Treatment of the gut-brain axis in ADHD¶
4.1. Probiotics for ADHD¶
For background information on gut bacteria, gut-brain axis and their role in the development of ADHD, see Gut bacteria, gut-brain axis (gut-brain axis) In the article Age-independent physical stress as an environmental cause of ADHD in the chapter Development.
Various studies report positive effects of probiotics in children with ADHD.
- L. rhamnosus GG
- Administration during the first 6 months of life reduced the risk of later ADHD
- Giving children improved ADHD symptoms in the parent rating, but not in the teacher rating
- B. bifidum Bf-688
- Administration to children improved inattention, hyperactivity/impulsivity, increased weight
- Firmicutes reduced
- Ratio of Firmicutes to Bacteroidetes (F/B ratio) reduced
- Proteobacteria increased
- B. subtilis, B. bifidum, B. breve, B. infantis, B. longum, L. acidophilus, L. delbrueckii, L. casei, L. plantarum L. lactis, L. salivarius, S. thermophiles
- Administration in addition to MPH improved ADHD symptoms in children compared to placebo
- L. reuteri, L. acidophilus, L. fermentum, B. bifidum
- Administration improved ADHD symptoms RS in children compared to placebo. In addition, serum high-sensitivity C-reactive protein (hs-CRP) decreased and total antioxidant plasma volume (TAC) increased compared to placebo. CDI and other metabolic characteristics unchanged.
- L. mesenteroides, L. paracasei, L. plantarum, B-glucan, inulin
-
ADHD symptoms in children and adults improved to the same extent in the treatment group and placebo group, ASD symptoms remained unchanged
A meta-analysis found no improvement with probiotics in ADHD.
4.2. Fecal transplantation for ADHD¶
To date, the studies needed to assess whether fecal transplants are a treatment option for ADHD are lacking.
One study found that mice whose guts were contaminated with gut bacteria from people with ADHD had structural changes in the brain (white matter, gray matter, hippocampus, internal capsule), decreased connectivity between motor and visual cortices right in the resting state, and higher anxiety than mice in which gut bacteria from people without ADHD were used.
A single case study reported an improvement in ADHD symptoms in a young woman with gut bacteria replacement related to a recurrent Clostridioides difficile infection.
5. Other substances for ADHD¶
5.1. Homocysteine¶
Homocysteine is not a vitamin, but an amino acid
A deficiency of folic acid, vitamin B2, B6 and/or B12 can cause an excess of homocysteine. Elevated homocysteine levels can have a neurotoxic effect.
One study found elevated homocysteine levels in ADHD correlated with increased hyperactivity/impulsivity
In contrast, a smaller study found evidence of homocysteine deficiency in children with ADHD.
5.2. Polyphenols¶
Polyphenols are aromatic compounds with two or more hydroxyl groups directly bound to an aromatic ring. Polyphenols are formed from phenylalanine, which in turn is formed from shikimic acid.
Natural polyphenols (of which there are said to be over 8,000) are often contained in plants as bioactive substances (colorants, flavorings, tannins), e.g.
- Flavonoids (colorants)
- Flavonoids appear to have a glutamate-antagonistic and GABA-agonistic effect.
- Anthocyanins (colorants)
- Procyanidins
- Benzoic acid derivatives, e.g.
- Vanillic acid
- Gallic acid
- Protocatechuic acid
- Cinnamic acid derivatives, e.g.
- Caffeic acid
- Coumaric acid
- Style derivatives, e.g.
Certain polyphenols are said to be able to influence neurophysiological changes caused by early childhood stress: e.g:
- Reduction of depressive symptoms through
- Xanthohumol
- Quercetin
- Phlorotannins
- Reduction of anxiety symptoms through
- Elimination of the BDNF reduction by
- No correction of the dopamine and serotonin level changes in the brain stem triggered by early stress
- Reduction of the cortisol stress response to acute stress through
One study found a correlation of increased polyphenol intake with reduced risk of ADHD in preschool children.
5.3. Phosphatidylserine¶
Phosphatidylserine is not a vitamin, but a phospholipid.
Source: Bieger.
