Dr Briffa makes recommendations that are not based on evidence.
To pick just one example: Dr Briffa points out that children who seem more prone to coughs, colds and congestion may have a sensitivity to dairy food. Briffa also claims that if this is the case, it can lead to an increase in mucus production. This seems to be based on the popular belief that dairy food is mucus-forming. However, it has been reported in the Journal of the American College of Nutrition (JACN) that: "milk consumption does not lead to mucus production or occurrence of asthma." The authors of the JACN paper also point out that: "Milk and milk products are the main source of calcium in the diet, and they contain eight additional essential nutrients. Needless avoidance of dairy products can lead to limited intakes of these essential nutrients." [Reference: Journal of the American College of Nutrition, Vol. 24, No. 90006, 547S-555S (2005)]
Briffa also recommends that parents could seek guidance from a nutritionist.
Anyone can call themselves a nutritionist. This title is not protected and practitioners are not regulated. There is no requirement for nutritionists to hold recognised qualifications. Those properly-qualified in nutrition are called dietitians and these practitioners are regulated.