well, that's a pretty dramatic take on what GP said.
there's a world of difference between literally starving and being unable to break focus on something to feed yourself and maintain a healthy weight and ensure that you're getting all the vitamins and nutrients your body needs to operate beyond a minimal level (especially as you age). i've definitely skipped multiple meals before while caught up in something and it ruins the rest of my day, my sleep, and impacts me moving forward beyond that til i can reach more of an equilibrium.
edit: i see from your other comments that you're not really willing to accept that some people have issues with their brains that make them behave differently from the idealized version of yourself that you hold in your head. so whatever. i hope you grow some empathy for others.
There is a difference between personal preference of taking a substance that changes focus by changing the way the brain works, and doing whatever work is required to use the brain to change itself. That's not to say taking a substance for all of one's life for focus is bad or good, or sustainable, nor is it to say that everyone has the ability or willpower to change the way their brain works.
Substances help in the short term, but they can't be the thing that "solves" the problem, no matter how it is presented (starving vs. good nutrition through attention to what one eats and when they eat). It can't be that a person can ONLY function with a substance dependence for mental phenomenon.
While mental health is a sensitive subject, I don't think it is a "protected" status given many humans suffer from bad mental health from time to time, or constantly, depending on their experience. We've all been in contact with some type of mental health issue with ourselves or others, and we should always approach it from a standpoint of empathy when dealing with others directly. Having empathy online is tricky, and usually involves just not saying anything as opposed to speaking what we think is the truth (for ourselves). Too many people fish for empathy online in my opinion, and real empathy is likely only delivered (well) in a person to person context. It is literally responding physically to another's emotions, as well as understanding why we should have empathy for their emotional output (and doing something besides crying with them in the moment). That is compassion.
In terms of my comment, it was based entirely on my protecting my children from being put on a drug that probably isn't good (or useful) for those of us that don't visualize, long term. There is ZERO evidence that taking amphetamines for long periods of time is good for you. Google lists this as one side effect of ADHD substances: "While some studies suggest positive effects on brain development, other research indicates potential negative impacts on the nucleus accumbens, an area of the brain related to motivation and reward."
Need data one this one. I don't believe anyone has starved because they didn't have the executive function to feed themselves.