I'm not sure that eating whatever you want is necessarily a good idea. How accurate are your instincts to begin with, and how do they deal with foods designed to be addictive? But much of the advice is excellent, like being gentle with yourself and the importance of paying attention to your body's signals, especially in terms of observing how you feel after eating different things. If you want to be happier, however, this approach is probably much more effective than most others -- and happier tends to correlate with healthier.
One interesting thing I've noticed is that sometimes I want to eat things that don't actually taste all that great. It started with the dragonfruit, which is rarely as sweet a fruit as it's meant to be, although that one has grown on me over time. The sheep milk yogurt was another -- that stuff was really sour, but I finished the carton anyway. Took me a while to figure out that the urge there was probably driven by the potent life energy of 12 live cultures. So that's an interesting shift in food instincts. I never have liked a lot of modern things like artificial colors and sweeteners, most of which are inedibly bitter to me, so brightly colored manufactured foods are a turnoff while brightly colored fruit draws me in.
There seems to be some flexibility of instincts to adapt to local foods, but with megacorps engineering food to be addictive, I'm not sure how much individual instincts can compensate for that.