I love caffeine and it is a much-needed morning staple to help get me going every morning. As real estate professionals, I'm sure you need caffeine for the same reasons.
But I'd like for you to consider drinking black coffee over other caffeinated options before your first showing in the morning and I'll tell you why.
Coffee has so many health benefits. Antioxidants are just one of those.
Why do we drink caffeine in the mornings? Because it's a stimulant. It gives us that jolt of energy we need to handle that tough client. When you consume it in moderation, it can be very beneficial.
Green tea might be a good choice if you struggle with insomnia or anxiety. But if you need to be alert, coffee would be the better choice. Both drinks have antioxidants and polyphenols (which have anti-cancer properties).
Energy drinks are not a good choice because they are full of sugar. The caffeine content is almost the same as black coffee and with ingredients, you can't even pronounce, I would just stay away.
Adding cream to your coffee will add calories and fat content, whereas black coffee has none. Adding milk, however, can reduce the acidity of the coffee if you have stomach issues.
If you are curious about other coffee add-ins see this post.
If you are thinking about a soda, steer clear as well. This one will have tons of sugar and don't be fooled by the word diet. It will just replace the sugar with artificial sweeteners. Coffee will have more caffeine anyway.