This will be long, but if you think ADD/ADHD is not real, please read it.
ADHD and all other mental disorders are not likely on the rise. With modern medicine, we just know much more about them and can easily identify them. The brain is complicated, and I am not surprised that things seem to frequently go awry. We now have treatment to fix them, so why wouldn't we?
A lot of people don't really understand ADHD... it's not laziness or any of that, given that there is a fine line between the two.
It is a regulatory disorder. You can't regulate emotions, intentions, or motivation. An ADD/ADHD child can focus on a video game for a LONG time (incorrectly known as hyperfocus) because they cannot regulate their intentions. They should have stopped what they were doing hours ago, but they didn't. They have awful working memory which controls the impulses that remind you of what you should be doing in the moment, so their brain does not remember to tell them to do things that they should be doing. It's like when you walk into a room and forget why you're there, except it happens frequently. They forget that they should be doing homework while doing homework and instead they are off in daydream land thinking about other things. It is not their fault. This is a result of a deficiency of neurotransmitters in the brain, mainly dopamine.
I spent years thinking ADD/ADHD were overdiagnosed, "made up" disorders, and they are very real. I recently started thinking I had it about 5 months ago and got diagnosed just a week ago. There is lots of evidence that suggests it is overdiagnosed, and lots to suggest it is only more common than previously thought.
It's awful not being able to understand things and be unable to channel your focus where it should be, especially in today's college-oriented world. That's where shit was unraveling for me since it was more difficult to teach myself to be accountable for myself and it felt terrible, especially when I did exceptionally well in highschool. This is common for late-diagnosed ADHD-PI(aka ADD) people. If you are "smart", you slip through the cracks.
When I took the intelligence scale test (WAISC if you feel like wiki-ing), I got the highest score possible for verbal reasoning and very high for perceptual reasoning. I scored in the 34th percentile for processing speed and 40th for working memory. This dissonance is indescribably frustrating and I can't even begin to tell you what it is like. It is a red flag for ADD/ADHD. It feels like one part of your brain wants to surge ahead and no matter how hard you try the other part of your brain just will not pick. up. the fucking. slack.
Part of ADD/ADHD is the insecurity and the being unsure of oneself that comes from years of feeling like an underacheiver and ridicule from lifelong failures. This whole "ADD is not real" attitude does not help those who have it. The disorder comes with a lot of self-doubt and that includes questioning your diagnosis and feelings of worthlessness. It only compounds those feelings when you insinuate that the disorder is not real. I spent months feeling like I was taking fucking crazy pills because deep down I knew something was wrong. I wanted to succeed and ace my classes so bad that I would spend HOURS longer in the library than any of my roomates (all the same major) only to see them succeed way ahead of me while I dropped a class and failed the other two out of the four I was taking.
This whole time I had my parents and friends telling me I was psyching myself out and that I didn't have ADD and I just needed to try harder, when I literally could not.
It's a chemical imbalance in the brain, and medications fix this. There are other ways, but medication is the most efficient.
If you're going to go around spouting ignorant shit about the legitimacy of the disorder, at least take some time to listen to the other side before you do it.