Your body is like an accountant. If food ($$$) is only coming in twice a day then its not going to want to dip into its fat stores (savings) because it may be a long time till more food ($$$) comes in, in fact it may slow your metabolism (cut costs) and store fat (save for a rainy day). If food ($$$) keeps coming in regular shorter intervals then it doesnt worry where the next batch of energy ($$$) is coming from so it will use up its fat stores (savings) more readily.
Are there any negative effects to having a very low bodyfat % of say 2 %? I tend to think of Bruce Lee having the perfect body and hit BF% was between 1 and 2 towards the end of his life.
Some vitamins & minerals need fat to absorb them to get into the body. Visceral fat (around organs) is used as protection from trauma for your organs. Other than those 2 things I cant think of any. Bruce Lees BF% was never that low because you need about 3% to live.
I'd say I'm average build at best and I'm an inch shorter than you and 15lbs heavier. You're skinny mate especially at 6% body fat if that is correct. I don't think I have ever been 6% body fat even when I ran loads and weighted 120lbs.
below 6 % is very unhealthy and a little bit lower is dangerous, i think its 4-5% are essential fats that your body cannot function without.