https://joelniggphd.com/wp-content/uploads/2017/10/switch.jpg 427 640 Joel Nigg https://joelniggphd.com/wp-content/uploads/2017/04/high-res-cover-1-1-200x300.jpg Joel Nigg2017-10-19 06:47:072017-10-19 06:47:30Cause and Effect in ADHD- Sorting Out the Difference
Cause and Effect – Obesity
Comprehensive studies, including one published by our group, now show that ADHD is correlated with being overweight/obese. In our review, we noted that this effect is more pronounced in adults than in teens or children. In fact, for pre-pubertal chidlren with ADHD, the very few data available do not suggest they tend to be overweight. This developmental pattern implies that ADHD may be a risk factor for obesity. it is easy to speculate that ADHD might lead to more impulsive or undisciplined eating, for example. But there may be biological linkages too. One possible linkage is dopamine functioning in the brain. When dopamine levels are not optimal, motivation and attention falter, and craving can set in for sugary foods (as well as for drugs, in some individuals). However, another possible linkage is inflammation in early development–some research suggests both genetic and environmental triggers in early life that could drive both ADHD and obesity as outcomes sharing a similar outside cause. Overall, the correlation of ADHD and obesity provides a possible further clue to the biology of both conditions, as well as a flag for clinicians to monitor individuals with ADHD for health outcomes.
Cause and Effect – Consult the Science
One of the mysteries of ADHD, like many mental, emotional, and behavioral health conditions, is that it is difficult to establish cause and effect. For example, many children with ADHD have problems on psychological tests of cognitive abilities like executive functioning. Is this cognitive weakness part of the cause of ADHD, or more like another symptom of the condition? It is very difficult to tell. This is why in Getting Ahead of ADHD we place so much emphasis on prospective studies (to see what comes first–consistent with cause but does not prove it), on randomized experiments (which prove causality but are difficult to do in humans), and on other clever designs that provide some evidence about causality, like genomic stratification designs (highly suggestive but not as definitive as randomized experiments). From those studies we now know that several environmental inputs do in fact have a causal influence. For example, we know that omega 3 (“good fat”) levels in the body both improve the development of attention in babies and influence ADHD symptoms in children. We know that exposure to lead has a causal influence on ADHD symptoms. These are not merely correlations. But we know the effects are not total–these are not sole causes. We also know the effects vary–some kids are more susceptible than others. Therefore, these findings lead to more scientific questions, that we are now studying, like: How big are those effects? And what is the individual variation–who is most affected? Stay tuned as we try to learn more.