3. Risks of ADHD in newborns and infants

Bottle feeding increases the risk of ADHD, while breastfeeding reduces the risk. Crying babies, feeding and sleeping problems in infants, subependymal pseudocysts and antihistamines in the first years of life increase the risk of ADHD.

• 3.1. Screaming children (up to + 1181 %)
  • 3.1.1. Increased risk of ADHD in crying children
  • 3.1.2. Factors that increase the risk of crying children
• 3.2. Febrile convulsions in premature babies (+ 540 %)
• 3.3. Bottle feeding increases (up to +200%), breastfeeding reduces ADHD risk (-23% to -74%)
• 3.4. First-born status (+ 31 to + 100 %)
• 3.5. Type of complementary food (wheat + 8 %, rice - 26 %)
• 3.6. Feeding problems with infants
• 3.7. Sleep problems in infants
• 3.8. Subependymal pseudocysts
• 3.9. Valproate
• 3.10. D-3 insufficiency in the first 12 months
• 3.11. Uncontrolled metabolic decompensation
• 3.12. Kawasaki syndrome

3.1. Screaming children (up to + 1181 %)¶

3.1.1. Increased risk of ADHD in crying children¶

Cry babies have a significantly increased risk of ADHD.¹² The risk of developing hyperactivity at the age of 8 to 10 years was 11.8 times higher (plus 1181%). Behavioral problems and a negative emotional orientation were reported twice as often as in those not affected.³

3.1.2. Factors that increase the risk of crying children¶

If the parents are heavy smokers, or if the mother smokes during pregnancy, the risk of a crying child increases by 30 to 150% (several studies); the largest study on this (n = 5845) states a 69% increased risk.⁴
In addition, there are several other possible causes that should be systematically ruled out.⁵

3.2. Febrile convulsions in premature babies (+ 540 %)¶

Febrile convulsions increased the risk of ADHD in premature infants 6.4-fold and the risk of ASD 16.9-fold.⁷

3.3. Bottle feeding increases (up to +200%), breastfeeding reduces ADHD risk (-23% to -74%)¶

The % figures were calculated without the highest and lowest values.

The WHO recommends exclusively breastfeeding newborns for the first 6 years.⁸
A cohort study in Taiwan found that of Taiwanese mothers⁸

• 82.1 % breastfed after delivery
• the average duration of breastfeeding was 2 months (59 days)
• 26 % breastfed for 3 months
• 9.8 % breastfed for 6 months
• 21.9% have ever exclusively breastfed their child (average duration of breastfeeding here 125 days)
• only 3.8% adhered to the WHO recommendation of exclusive breastfeeding for up to 6 months

Infants who were not breastfed showed an increased risk of ADHD as children, while children who were breastfed as infants showed a decreased risk of ADHD ^{9 10 11 12 1314}

• 3.71-fold ADHD risk (+ 271 %, OR = 3.71; meta-analysis of k = 11 studies).¹⁵
• almost 3 times the risk of ADHD (+ almost 200%)¹⁶
• approx. 1.55-fold ADHD risk (+ 55 %, OR = 1.55; METASTUDY)¹⁷

Children with ADHD were 1.51 times more likely to be exclusively breastfed for less than 3 months and 52% less likely to be exclusively breastfed for more than 3 months. Children with ADHD had a significantly (2.44 months) shorter duration of breastfeeding (SMD: Hedges’ g = - 0.36) (meta-analysis of k = 11 studies). ¹⁵

In breastfed children (without distinction as to whether exclusively or partially and regardless of duration), the risk of ADHD was

• by 83 %¹⁸ and for major depression by 74 %, and for anxiety disorders by 4 %. The effects on ASD, bipolar Disorder and schizophrenia were not significant.
• reduced by 74 % (OR = 0.263, small study)¹⁹
• by 30 % (meta-analysis, k = 12, n = 106,907).²⁰
• reduced by 28% (raw value) to 18% (adjusted value) by the age of 5⁸ Since ADHD is usually diagnosed later, the impact is likely to be much greater,
• unchanged²¹

Children who were exclusively breastfed had a higher risk of ADHD compared to children who were exclusively bottle-fed,

• reduced by 38% with exclusive breastfeeding for at least 6 months, after adjustment for potential confounding factors²²
• hyperactivity reduced by 35% at 8 years of age if breastfeeding was exclusive for at least 3 months²³
• reduced by 18 %²⁴
• reduced by 7 %²⁵
• unchanged ADHD symptoms at the age of 16²³

Exclusive breastfeeding for more than 6 months increased the risk of ADHD by 15%.⁸

Partially breastfed children had a

• aDHD risk reduced by 44% at the age of 4 years, after breastfeeding for more than 12 weeks²⁶
• aDHD symptoms reduced by 32% at age 16 if breastfed for at least 6 months²³
• hyperactivity reduced by 24% at 8 years, but not statistically significant²⁷
• aSS risk reduced by 11 % ²⁴
• aDHD risk reduced by 9 %²⁴
• improved executive functions at the age of 4 years (increase of 4.9 points after breastfeeding for more than 20 weeks)²⁶
• improved social skills at the age of 4 years (43% reduced risk of being in the worst 20% after breastfeeding for more than 12 weeks)²⁶

The risk of ADHD decreases with the duration of breastfeeding^{2829 30} (25-year observational cohort study, n = 16,365).³¹. One study found no significant values for ADHD.³²
The risk decreased by

• 20% if breastfed for more than 1 month compared to less than 1 month (meta-analysis, k = 12, n = 106,907).²⁰
• 33% if breastfed for more than 3 months compared to less than 3 months (meta-analysis, k = 12, n = 106,907).²⁰
• 50% if breastfed for more than 6 months compared to less than 6 months (meta-analysis, k = 12, n = 106,907).²⁰
• 55% if breastfed for more than 12 months compared to less than 12 months (meta-analysis, k = 12, n = 106,907).²⁰

Each additional month

• the duration of breastfeeding reduced the risk of ADHD by 8%²²
• of exclusive breastfeeding (without complementary food) reduced the risk of ADHD by approx. 8 % (but not statistically significant)²²

Prolonged breastfeeding improved cognitive performance,³²

Complementary food at the age of 6 months

• Complementary food up to 6 months reduced the risk of ADHD by 28%⁸
  • by 6 % with fruit/vegetable juice (not statistically significant)
  • by 14 % with fruit/vegetable porridge (not statistically significant)
  • by 19 % with traditional rice porridge (Taiwan) (not statistically significant)
  • by 27% with rice-based diets without traditional rice porridge (Taiwan)
  • increased by 8 % with solid food made from wheat (not statistically significant)
• had no influence²⁴²²

The risk of ASA was reduced by breastfeeding

• by 36 %²⁴
• significantly due to prolonged breastfeeding³²
• not significant¹⁸

Breast milk contains many substances that are essential for the development of babies, such as

• polyunsaturated fatty acids.¹¹
• Prebiotics³³
  • Oligosaccharides
  • promote the growth and activity of beneficial microorganisms

The substances contained in breast milk promote³³
- antimicrobial active ingredients
- bacterial growth
- secreted IgA for a regulatory immune system

Styles in the first three months of life influenced the intestinal microbiotics:³³

• increases the frequency of
  • Lactobacillus (Bacillota strain)
  • Bifidobacterium
  • Enterococcus
  • Corynebacterium
  • Propiobacterium
  • Streptococcus
  • Sneathia
• reduces the frequency of
  • Bacteroides (strain Bacteroidota)
  • Staphylococcus

Bottle-fed infants show a different gut microbiome:³³

• increased frequency of
  • Atopobium (strain Actinomycetota)
  • Bacteroides (strain Bacteroidota)
  • Bilophila (strain Thermodesulfobacteriota)
  • Enterobacter (strain Pseudomonadota)
  • Escherichia (strain Pseudomonadota)
  • Citrobacter (strain Pseudomonadota)
  • Clostridium (Bacillota strain)
  • Enterococcus (Bacillota strain)
  • Lactobacillus (Bacillota strain)
  • Granulicatella (strain Bacillota)

More on the influence of the gut-brain axis on ADHD at Gut-brain axis and ADHD

Bisphenol A is known to increase the risk of ADHD. Exposure to PAHs, particularly bisphenol A (BPA), is associated with ADHD symptoms in primary school children and a significant reduction in the volume of the caudate nucleus³⁴³⁵ Bisphenol A was much more common in baby bottles in 2007 than in 2011, which could explain why a study found a five-fold increase in the risk of ADHD in children fed by bottle in 2007, but no increase in risk in children fed by bottle in 2011.³⁶

After all, breastfeeding has its own influence on the well-being and positive development of children, independent of food intake.
Maternal care is the infant’s first social experience and has a decisive influence on its survival, proper development and social skills throughout life.
Infants and puppies do not yet have a high inherent value for their respective mothers at birth.³⁷. Breastfeeding in humans and suckling puppies in animals are rewarding and reinforcing stimuli that promote maternal behavior and bonding. Nursing puppies activates the mesocorticolimbic dopamine system in mothers, which reinforces bonding and nurturing behavior. Extracellular dopamine levels in the nucleus accumbens (the reward center of the brain) increase and correlate with the amount of time spent caring for the offspring.

3.4. First-born status (+ 31 to + 100 %)¶

The risk of ADHD in first-born children was

• By 200% compared to children with younger and older siblings, according to a large Spanish registry study.³⁸
• Increased by almost 100 % compared to non-firstborns³⁹
• Increased by 70 % if there was only one (1) sibling⁴⁰
• Increased by 35% according to a Spanish study of n = 1,104 primary school children⁴¹
• According to the German KiGGS study (n = 13,488), the risk of ADHD was 31% higher for first-born children compared to last-born children and children without siblings.⁴²
• Increased by 22 %⁴⁰
• A very large Swedish registry study found an increased risk of ADHD and depression for firstborns.⁴³
• An Indian study found a high proportion of first-born children among people with ADHD⁴⁴
• A study of Ethiopian students found a significant ADHD risk increase for first-time mothers⁴⁵ and explained this conclusively by increased perinatal risk factors and birth-related complications, which are a major contributor to ADHD and are so much more common in first-time mothers that they were labeled high-risk by the authors:⁴⁶

• low birth weight 57% more frequently (evidence that this increases the risk of ADHD)
• Emergency caesarean sections 57 % more frequent
• pregnancy-induced high blood pressure 15.38 % more frequently
• intrauterine growth retardation 19.23 % more frequently
• premature labor 9.61 % more often
• fetal distress 19.23 % more frequent
• Oligohydramnios (amniotic fluid deficiency)17.30 % more frequent

It remains to be seen whether there are other risk factors.

No influence of first-born status on the risk of ADHD found

• a study of n = 598 children and adolescents with ADHD from relatively large families (more than 47% had at least 4 siblings)⁴⁷
• an Iranian study on n = 400 children⁴⁸,
• a study of n = 387 Iranian students.⁴⁹
• two smaller studies (n = 100 and n = 32)⁵⁰
• a smaller study (n = 173)⁵¹

First-born status increased the risk

• By 45 % for aggressive behavior. The risk was even higher if there were older siblings.⁵²
• By 28 % for severe externalizing symptoms⁵³

Children with ASD had a significantly reduced risk of ADHD if they had an older sibling⁵⁴

One study did not ask about first-born status, but about the presence of siblings (at 18 months, 3 years and 5 years of age). The siblings could be older and or younger. Among the newborns, about 50.4% were their mothers’ first child and 38.4% were their second child. The remaining newborns were other children.⁵⁵
Siblings reduced the risk of ADHD by 35%.⁸

3.5. Type of complementary food (wheat + 8 %, rice - 26 %)¶

Complementary food at the age of 6 months

• Complementary food up to 6 months reduced the risk of ADHD by 28%⁸
  • by 6 % with fruit/vegetable juice (not statistically significant)
  • by 14 % with fruit/vegetable porridge (not statistically significant)
  • by 19 % with traditional rice porridge (Taiwan) (not statistically significant)
  • by 26% with rice-based diets without traditional rice porridge (Taiwan)
  • increased by 8 % with solid food made from wheat (not statistically significant)
• had no influence²⁴²²

3.6. Feeding problems with infants¶

Feeding problems in infants correlate with ADHD in adolescence and adulthood.²
Frequently skipped meals correlated with an increased risk of ADHD.¹³

3.7. Sleep problems in infants¶

Sleep problems in infants correlate with ADHD in adolescence and adulthood.²

3.8. Subependymal pseudocysts¶

Subependymal pseudocysts in newborns increase the risk of ADHD and autism.⁵⁶

3.9. Valproate¶

Studies in mice suggest that valproate administration in newborns could cause permanent damage similar to that caused by ASA and, in some cases, ADHD.⁵⁷

3.10. D-3 insufficiency in the first 12 months¶

A vitamin D3 level of less than 25 ng/ml in the first 12 months of life was dose-dependently associated with an increased risk of ADHD in childhood. This also applied to ASD and emotional behavioral disorders⁵⁸
This is consistent with the findings of an increased risk of ADHD if the mother has a D3 deficiency during pregnancy (see there).

3.11. Uncontrolled metabolic decompensation¶

Uncontrolled metabolic decompensation, e.g. as a result of MCAD deficiency (Medium-Chain Acyl-Coenzyme A Dehydrogenase Deficiency), increases the risk of missing developmental milestones and developing aphasia and ADHD.⁵⁹

3.12. Kawasaki syndrome¶

Kawasaki syndrome is a febrile vasculitis of infancy and early childhood.

A meta-analysis of k = 4 studies with n = 1,454,499 subjects found a 76% increased risk of ADHD in people with ADHD.⁶⁰
One study found an increased prevalence of ADHD in people with ADHD⁶¹, other studies found only a tendency⁶² or no association.⁶³