Noakes is a marathon runner (70+ run) who ate the prescribed high carb diet, he even wrote a book titled "The Lore of Running" in which he promoted high carb for athletes. Despite being fit and eating a "healthy diet" he developed T2 diabetes.
He became an advocate of low carb eating and in this talk he discusses how a high carb diet interacts with individual genetics to produce T2 as well as why high fat low carb is not dangerous. He supports his thesis with lots of studies. It's also refreshing to hear him say something hasn't been studied and so we don't know the answer to that question.
The lecture is a valuable primer about why current main stream medical advise is wrong concerning the causes of T2 ie. eating too much fat and getting too little exercise causes T2. One point he makes is that our individual metabolisms vary and while some of us do just fine with high levels of carbs it is a disaster for others.
The video is long but well worth watching. Although it does talk at length about T2 and metabolic syndrome, I think T1's would also benefit because he spends time exploding various myths concerning LCHF as well as lots of general information about how our bodies work.