Warm/ Cold Formula bottles

So its been 12 yrs since my youngest had bottles Im now 17 weeks pregnant and recently I have seen posts about giving babies cold formula bottles. When my older children were younger I was always informed to heat the bottles as cold can cause upset tummy and wind pain in your LO. Also we always used boiled water not tap water which some mothers are also now doing. Has new research changed the preparation of formula? Wanting to know whats best form my LO please. Any help would be appreciated. Thanks.