They say avoid the ABCs- thats apple banana and cereal (like baby rice cereals). All can cause constipation. If you steam pears, add a handful of sultanas and then purée it all together. Works a treat!
With the not giving too much sweet fruit solid foods to avoid a sweet tooth I just don't get that idea..... Breast milk is very sweet so lots of babies are already used to sweet tastes and they get used to other flavors just fine. I give vege/meat purée first and then fruit purée at every meal and I don't think this will cause a future problem at all.