User blog comment:Kaido King of the Beasts/Chapter 840: My Worthless Son/@comment-178.118.6.212-20160921142830/@comment-2125188-20160921193207

I think he is for the most part a normal, but I do think the modifications did have a little affect on him. But I think Sanji's true strength comes from all the hardships he's been through. I bet his siblings hardly train at all and nowhere near as hard as he did (cause if they did train hard, there's no way Sanji would've been able to catch up to them). I also think due to being a chef, he has learnt how to look after his body well. And Sanji has had more valuable battle experience. Most of Sanji's battle's are hard fought against very credible opponents, while his siblings would most likely not even have to try in their battles.