More FAQ about ADD/ADHD
3. What are the theories about causes of ADD,ADHD?
There have been many theories about the cause of ADD/ADHD but there is no consensus among the experts.
a) brain injury – caused by trauma or disease – this was one of the first theories however current thinking suggests that this causes relatively few cases
b) delayed brain maturation – the brain is simply slow in developing some of its functions and it will eventually catch up – there is little direct neurological evidence supporting this theory
c) toxic poisoning – this theory says that the brain has been assaulted by a toxic substance that has disrupted development – examples: lead poisoning, prenatal use of drugs or alcohol
d) food additives – this was a major field of study in the 1970’s and 80’s led by Dr. Benjamin Feingold who believed hyperactivity was caused by artificial flavours and colouring. Rigorous scientific studies do not support this theory.
e) allergies – there is limited evidence to suggest a link between environmental influences and ADD/ADHD
f) medical illness – some medical conditions mimic ADD/ADHD symptoms ( see a previous posting re: differential diagnosis)
g) medications – some meds trigger ADD/ADHD symptoms (examples: Dilantin, Dimetapp, cold medicines)
h) heredity – an ADHD child is 4 times more likely to have a close relative with ADHD than a child without ADHD “chip off the old block”
i) family stressors – divorce, poor parenting, poverty, attachment disorder, etc.
j) brain chemistry – medical community by and large supports this theory. It appears that ADD/ADHD sufferers have unbalanced levels of the neurotransmitter dopamine.
The bottom line:
- experts do not know what causes ADD/ADHD
- there are probably a combination of factors leading to ADD/ADHD
- research continues