LCT and hyperinsulinemic hypoglycemia, familial, 4: This, however, contrasts with the risks in normal children as demonstrated by Gabr and colleagues in Egypt [13], a difference attributed to the fact that in normal children, lactose intolerance is mainly due to primary lactase deficiency which increases with age (becomes apparent by 5 years of age), as opposed to secondary lactase deficiency which, though can present at any age, is more common in infancy [11].