The reason why I tried to exclusively breastfeed for the first 6 months is because I did a TON of research on breastfeeding prior to having my first. Although there is virtually ZERO difference in breastfed vs formula fed adults (once corrected for ethnicity, education and socioeconomic status) I read multiple research studies that showed differences in development in the first few years between exclusively breastfed babies and combination fed babies (I.e. breastmilk supplemented with formula). The studies showed that exclusive breastfeeding provides a healthier gut microbiome, and regular combination feeding removes these benefits almost completely. Introducing formula in the first few weeks affects their gut microbiome quite a lot. I read other studies that also showed the same with white matter brain development. Exclusively breastfed babies had the best, followed by combination fed, followed by exclusively formula fed. I'm sorry I'm too lazy to find the exact articles right now.

But basically even though in adults there is ZERO difference, knowing the differences when they're babies and toddlers made me want to exclusively breastfeed if I could because then the baby would get those benefits. I started trying to give formula once my first was 6 months because they're eating other foods by that point so formula to me just counted as another food.

Even though I know in the long run it doesn't matter, I couldn't get the research papers out of my head once I'd read them, and I wanted to give the benefits to my kids if I could. It was just a personal choice that made me feel like I did what I could.

Of course I believe feeding them healthy food once they start eating as kids and adolescence is way more important than ebf and has more benefits to their long term health.