Best Foods
The best foods to start weaning your baby with are ones that are (1) nutrient dense and (2) easy to prepare and purée. Ultimately the goal is to get your baby eating a puréed version of what you eat, then finely chopped and mashed for older babies, moving towards finger food portions for toddlers. If possible, invest in organic produce, at least for the first 2 years of your child's life, as this is the period they are the most susceptible to pesticide residues.
I absolutely don't believe in kids meals. If your diet isn't very healthy, now is a really important time to clean your act up. Children will mimic their parents’ eating habits. Eat with your child at the table as often as you can. While it isn't always possible to have family meals, someone should always be a sitting with baby at the table for safety and to model social skills and table manners. So eat healthy, sit at the table, turn the TV off, put phones away and engage with your baby and family.
The requirements of a formula fed versus breast fed baby vary slightly. Formula fed babies are often lower in beneficial bacteria than breast fed. It would be my priority to establish a good microbiome in formula fed babies especially if they have signs of eczema, cradle cap or recurrent infections. You can do this by (1) including probiotic rich foods such as yogurts and (2) prebiotic containing foods to help feed and maintain beneficial bacteria colonies.
A breast fed baby on the other hand, provided antibiotics haven't been used and was delivered vaginally, will be requiring iron rich food around the 4-6 months mark as the iron stored in the liver from birth will be starting to deplete. Vitamin D level could potentially be low if the pregnancy or delivery was in the winter months and iodine if mother’s diet is lacking.
"Ultimately the goal is to get your baby eating a puréed version of what you eat, then finely chopped and mashed for older babies, moving towards finger food portions for toddlers."
Commercial Baby Foods
Commercial baby foods are no replacement for homemade fresh meals but are fine occasionally as "emergency food". Store bought baby pouches and jars are heat treated to ensure a long shelf life, which means they are low in nutrients, particularly water-soluble vitamin B's and C. Generally they are packed full of fruit to make them palatable, which means they are full of sugar. Alway read the labels and check for sugar content. The World Health Organisation (WHO) recommends that sugar intake shouldn't exceed 5-10% of total daily calorie intake for babies, children or adults. For a child, this is roughly 3 teaspoons or 12 grams. If you look at the nutrition panel of most baby food pouches, you'll find a lot of the fruit-based ones contain around a whooping 15 grams of sugar. Try to choose a vegetable based one with some protein such as quinoa or meat that is in a glass jar or in BPA-free pouch.