1. There's no such thing as good / bad cholesterol. This is complete baloney and Pfizer lost a staggering amount of money when a drug raising good cholesterol got as far as human trials -- and failed them. There is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of coronary heart disease or cardiovascular disease. There's growing amount evidence though that cholesterol is a symptom and not a cause.
2. The diagnosis and treatment of ADHD in adults but most especially in children is extremely suspect. Last year there was a study pretty much confirming it is overdiagnosed in children. But even worse, whether ADHD is even a thing or multiple conditions wrongly bundled under a single name is basically an open question. We basically put labels on children with "problematic behaviors" like "autistic spectrum disorder" and "ADHD" and then eventually find that 30-80% of ASD children are meeting criteria for ADHD. First of all what sort of study is 30-80%? But if the higher end is true, the question strongly arises: are these even two things?
3. I would bet dollars to doughnuts in a few decades we will look at all current nutrition advice to something akin of medieval quackery. How is this not self evident: genes obviously affect how foodstuff interact with our bodies thus any sweeping generalization is inherently suspect or most likely complete baloney. Like, how can anyone seriously think only lactose intolerance is an inherited genetic trait.
I would need to dig into my notes if someone needs them but a group of statisticians at a university started to look into medical studies and then FOIA the raw data and found like 80% of them cherry picking the data.
The incentives are not exactly at the right place.