Brief Answer:
Breast feeding would be the best

Detailed Answer:
Thanks for asking on HealthcareMagic.

Let me emphasize on the fact that breast milk is the best possible milk for a baby and there can be no alternatives for the same. Most formula milks are cow milk based and hence difficult to digest. Moreover they make the child more prone to complications and infections. Mother's breast milk is produced on the demand of the baby. Hungrier the baby, more vigorous is the suck. More is the suck, more is the amount of breast milk produced. Giving formula automatically reduces the demand of the baby and thereby the production of breast milk. All you need to do is to switch back to exclusive breast feeding and the production will increase automatically. All you need to do is to monitor the urine output. If the frequency is more than 6 times in 24 hours, you would know that the amount of feeding is adequate. If the amount of passage of urine is less or if the child is lethargic you would need to take the child to a doctor without delay.

For a baby of this age, it is normal to pass stool several times a day or even after each feed. Alternatively the child may pass stool once in 10 days and that is normal too.

If you still need to give him formula milk, let me mention that Enfamil and Nusobee Soya are soy based whereas NAN Pro 1 is cow milk based. Unless there is a suspicion of cow milk allergy or lactose intolerance you need not give low lactose formula or soy based formula and so you can continue with NAN Pro 1. The vomiting once a day seems to be rather due to not being able to tolerate formula milk well. This does not seem to be occurring due to cow milk allergy. Switching back to breast milk should help in resolution of this problem. Enfamil or Nusobee Soya have poor taste but you can try them and see if there is a difference in this behaviour.

Let me know if I could help further.

Regards

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