Do you mean your DH? Not being funny but is he an trained nutritionist? Do you know where he gets this information? Unless you have proper training and know where/how to find the truth there is a lot of misinformation/bad information out there, particularly on the internet. Especially for child athletes, as most of it stems from adults seeking a quick weight loss fix (atkins, paleo, low fat etc..)
I had a meeting with a national squad nutritionist recently, who specialises in child athletes. His overall message was to ignore anything you've ever read on high carb, low carb, high protein, low salt, low fat, calorie controlled diets. It's all incorrect, and especially where children are concerned. The main advice was child athletes should have a balanced diet- the old food triangle and protein/carb/fat ratio. Food choice should just be sensible- home cooked rather than processed, watch out for so-called "healthy" snacks like cereal bars which have no nutritional value, etc. Not to restrict salt, either...
Salt is actually necessary for muscle function as sodium and chloride ions are essential for nerve impulses- restrict salt in an athlete who works out hard and loses salt through sweating = big problem. High protein in a child can affect kidneys. This might be OK in an adult who is not training 20 hours a week, but not a child who is.
There is so much cr*p out there regarding food these days!