frustrated boy
According to Neurologist Richard Saul who has written a book called "ADHD Does Not Exist: The Truth About Attention Deficit and Hyperactivity Disorder", the amount of people who are suffering from Attention Deficit and Hyperactivity Disorder is zero.

Richard Saul is a neurologist who has had a long career in examining patients who have been having trouble with short attention spans and inability to focus. From his first hand experience, he feels that ADHD is nothing more than a fake disorder that is really only an umbrella of symptoms and not actually a disease. He strongly feels that it should not be listed as a separate disorder in the American Psychiatric Association's Diagnostic & Statistical Manual, all detailed in his book which is set to release in February 2014.

As it stands, ADHD is defined as a psychiatric disorder that is neurodevelopmental. In order for diagnosis, significant issues with attention and/or hyperactivity and acting impulsively that are not appropriate for a person's age must be present. The number of ADHD diagnoses has increased greatly in recent years due to the fact that doctors are using the disorder as a simple means to not only explain lack of focus or attention but also to allow the use of medication which can mean direct benefit for the doctor. Saul feels that many parents these days are looking for any way to get their kids to sit down and remain quiet and ADHD, and the medications that go along with it, can be the quick fix they are looking for. Currently, 1 in 9 children are labelled as ADHD and of that, two-thirds of them are on some sort of drug.

Unfortunately this solution is not an effective one as the drugs are dangerous and contain addictive stimulants. While many doctors are prescribing them without question, there should be a lot more thought that goes into addressing the root issue well before drugs are pushed. According to Saul, trying to treat something like ADHD as a disease is a big mistake. It can be seen as going into a doctor's office with heart pains and simply being prescribed painkillers. Yes, you may walk away pain-free for a few hours, but then you die of a heart attack. Without looking to the core issue, we cannot properly know what is going on.
"ADHD makes a great excuse, the diagnosis can be an easy-to-reach-for crutch. Moreover, there's an attractive element to an ADHD diagnosis, especially in adults. It can be exciting to think of oneself as involved in many things at once, rather than stuck in a boring rut." Richard Saul
Sources Used :

http://www.cdc.gov/ncbddd/adhd/diagnosis.html

http://nypost.com/2014/01/04/adhd-does-not-exist/

Pharmaceutical Company Influence On Characterization of Disorders
"The medical profession is being bought by the pharmaceutical industry, not only in terms of the practice of medicine, but also in terms of teaching and research. The academic institutions of this country are allowing themselves to be the paid agents of the pharmaceutical industry. I think it's disgraceful." - Arnold Seymour Relman, Harvard Professor of Medicine (source)
ADHD is classified as a mental disorder, which is interesting because the definition of these types of disorders in particular have been shown to be heavily influenced by the pharmaceutical industry. American psychologist Lisa Cosgrove and others investigated financial ties between the Diagnostic and Statistical Manual of Mental Disorders (DSM) panel members and the pharmaceutical industry. They found that, of the 170 DSM panel members, 95 (56%) had one or more financial associations with companies in the pharmaceutical industry. One hundred percent of the members of the panels on 'mood disorders' and 'schizophrenia and other psychotic disorders' had financial ties to drug companies. The connections are especially strong in those diagnostic areas where drugs are the first line of treatment for mental disorders. In the next edition of the manual, it's the same thing.
"The DSM appears to be more a political document than a scientific one. Each diagnostic criteria in the DSM is not based on medical science. No blood tests exist for the disorders in the DSMN. It relies on judgements from practitioners who rely on the manual." - Lisa Cosgrove, PhD, Professor of Counselling and School Psychology at the University of Massachusetts, Boston

The very vocabulary of psychiatry is now defined at all levels by the pharmaceutical industry." - Dr. Irwin Savodnik, an Assistant Clinical Professor of Psychiatry at the University of California at Los Angeles (source)
These are definitely some facts to take into consideration when it comes to dealing with your child's ADHD diagnosis. It's a 'disease' — one which I was also diagnosed with — that I personally don't even think is real. I think it was made up strictly for the purpose of making money.
Over the past two decades the pharmaceutical industry has moved very far from its original high purpose of discovering and producing useful new drugs. Now primarily a marketing machine to sell drugs of dubious benefit, this industry uses its wealth and power to co-opt every institution that might stand in its way, including the US Congress, the FDA, academic medical centers, and the medical profession itself. (Most of its marketing efforts are focused on influencing doctors, since they must write the prescriptions.) - Marcia Agnell,Harvard Medical professor and the former Editor-in-Chief of The New England Journal of Medicine,
Disorder or Creativity?

The last point in the above paragraph is pretty disturbing, particularly given the fact that recent work in cognitive neuroscience shows us that both those with an ADHD diagnosis, and creative thinkers, have difficulty in suppressing brain activity that comes from the "Imagination Network." There are no school assessments to evaluate creativity and imagination; these are admittedly difficult to measure and, accordingly, receive very little attention in the education system. Yet a lot of research is pointing to the fact that people who show characteristics of ADHD are more likely to reach higher levels of creative thought and achievement compared to those who don't show these characteristics.
"By automatically treating ADHD characteristics as a disability - as we so often do in an educational context - we are unnecessarily letting too many competent and creative kids fall through the cracks." - Scott Barry Kaufman, Scientific Director of The Imagination Institute in the Positive Psychology Center at the University of Pennsylvania (source)
While brain scans of people diagnosed with ADHD do show structural differences, it is a scary reality that a large portion of ADHD diagnoses are derived from the observations teachers make in school. Too often, children are diagnosed based on perceived behaviour alone, and then encouraged to take medication right away. These children are not actually tested or scanned; they and their parents are simply told that they have ADHD.
"I think the big mistake in schools is trying to teach children anything, and by using fear as the basic motivation. Fear of getting failing grades, fear of not staying with your class, etc. Interest can produce learning on a scale compared to fear as a nuclear explosion to a firecracker." - Stanley Kubrick