I've been on a low carb/high fat (a.k.a ketogenic) lifestyle for 18 months now. Prior to starting this, I weighed around 81 kg (I'm 6ft) and it had taken me a couple of years to get down to that from around 87Kg. Virtually eliminating carbs (especially sugar) meant I lost 8 kg in 8 weeks, and after about 3 months, my weight stabilised at 70 kg, and my beer gut, which previously I couldn't get rid off, has gone.
I only switched after doing a lot of research and reading up about it, including some very technical books by Drs. Phinney & Volek which went into a
lot of detail about the changes the body undergoes on a low carb lifestyle, and also about how much the food industry had pumped out the incorrect message in the last 40 years or more, by reducing fat and compensating for the resultant lack of taste by bulking up with various forms of sugar. There's also the naive view that eating fat means that fat is then deposited around the body and also raises cholesterol levels, which isn't the case. Sadly the UK medical industry is quite a few years behind the US, as in the States they're increasingly aware that carbs are the problem, not fat. In fact the diet was first used 100 years ago to help control epilepsy, but it's
only recently that they've understood the changes in the brain chemistry as to why it reduces or stops seizures.
I can quite easily do a 100 mile ride at 16 mph and not need anything to eat anything at all, as burning fat is all the body needs. You don't, and in fact can't bonk, as you're not needing to rely on limited supplies of glycogen, which for anyone eating carbs means they have to keep eating. So that also means no more sticky gels when on the bike. And the fact I get to cook and eat with butter & cream is nice as well.