There is such a story on the net that lemon juice is actually alkaline and helps with heartburn.
This, brothers, is stupidity. Lemon juice contains a lot of citric acid, which, being acid, acts on your mouth, esophagus and stomach just like... acid. That is, you will have a set of teeth, all the calcium will flow out of your teeth, the esophagus will be burned. If the esophagus has already suffered from reflux, then there will be heartburn. If the stomach was inflamed, then it will ache. Do you remember? Let's go further.
After citric acid is digested in our body, it turns into citric acid salts, which have alkaline properties. If such salts are excreted in the urine, they help dissolve crystals in the kidneys that could become stones.
Cystitis
Citric acid salts also help with cystitis. They don't kill the germs that cause cystitis, they just alkalize the urine.
With cystitis, the discomfort is largely due to the acid. If the acid is removed from the urine with cystitis, it will instantly feel better. Citric acid salts cope with this.
In those countries where it is not customary to treat cystitis in the first two days with antibiotics, sodium citrate powders turned out to be very fashionable. They are dissolved in water and drunk. After 40 minutes, the symptoms of cystitis have subsided. You can mix yourself with sodium citrate from baking soda and citric acid and try it.
Will sodium citrate help heartburn?
A little help. It was even used as an antacid in the early 80s of the last century. Now I have not seen this.
So why doesn't lemon juice help with heartburn?
Why are you so little, really? Forgot your school chemistry course? The acidic properties of lemon juice are determined by hydrogen ions, which citric acid releases into the solution. Citrate is alkaline only in the form of salt. Citric acid itself does not release harmless sodium or potassium ions into the water, as citrate does, but the purest acid in the form of hydrogen ions.
Remember drugs like omeprazole, which are called proton pump blockers, which are amazing at reducing stomach acid? They block the release of protons. This is the name given to positively charged hydrogen ions. This is pure acid. So citric acid gives these same hydrogen ions into the solution. She's sour. It provokes heartburn, stomach pain and dissolves tooth enamel. Available?