Oh yeah I saw a health newsletter on a forum yesterday containing some info about baking soda. (I'm glad to hear it was recommended to you too, Inika.)

What interested me most besides the judgmental remark at the beginning LOL was the last sentence. Apparently the lemonade and baking soda can be combined :

***Sodium Hydrogen Bicarbonate (Baking Soda/Powder)***

We all know baking powder. But there may be many people who are
against the use of baking powder, again and again. They are just
stupid people around us. Here, let us use baking powder for good
living.

Sodium bicarbonate is usually used for cooking or baking. You can rub
baking soda to meat, fish, and others for tendering. You can add a <--
teaspoon of soda to pineapple juice or any other drinks as health
drinks. Use it for cleaning your kitchen, stoves, dishes, and toys,
too.

Do you know that you can use baking soda for beauty purposes? Mix
soda with face creams. It will make your skin smooth, beautiful, and
healthy. How about baking soda poured to the washing machine? Doing
so will make your clothes whiter and better, so enjoy your laundry
work. Many people use only soda for laundry with washing machine. [ ]

Sodium bicarbonate can do a lot of things in our living. How about
cleaning of your pet? Your pet's fur will shine more and get
healthier.

Children love and enjoy sweet lemonade with sodium bicarbonate.

About the Author:
Junji Takano is a Japanese health researcher involved in
investigating the cause of various diseases since 1960.