Although formula has some conveniences, breastfeeding is far more advantageous by comparison.
A mother's breast milk is specifically tailored to her babies biology.
Breast Milk has antibodies that protect babies against infections, while formula does not.
Additives and vitamins in formula don't work as well as breast milk, are not as easily absorbed, and are more difficult to digest.
Breast Milk strengthens the immune system, formula does not.
Breast Milk has an analgesic effect, or pain reducer.
Breast milk is free, and requires no preparation.
There are developmental benefits as well.
Breastfeeding provides emotional bonding between mother and child with essential skin-to-skin contact.
Adults who were breastfed as babies generally score higher on intelligence tests than those who were fed formula.
Breastfeeding is also better for mothers.
Breastfeeding helps lose weight gained in pregnancy by burning calories.
It releases oxytocin, the "love" hormone.
It lowers the risk of breast and ovarian cancer.
Mothers who don't breastfeed can experience engorged breasts. This may result in pain, and breasts that do not return to their original shape and appearance.
"OK then, so why would a mother ever use formula?"
First, some mothers have issues such as low milk supply, are on medication, or have an infectious disease. Some mothers feel discomfort, or work long hours and are not sufficiently available, and some mothers just don't know that breastfeeding is ideal.
Other advantages of formula are:
Other people can feed the baby.
It can be done in public.
You can regain some independence.
So what about storing breastmilk?
Refrigerating can be done, and the milk is good up to five days.
Freezing can be done as well, and the milk can last even over six months. However, it loses some essential nutrients, but will still be better than formula.
(Click here for my best formula picks and breastfeeding supplies!)
Summary
All things considered, breastfeeding is significantly better for the baby and mother, both biologically, and emotionally. If you can breastfeed, do breastfeed.