Whether baking soda works or not, eating a healthy diet with lots of leafy greens is a proven way to reduce inflammation in the body. Getting the right amount of vitamin D is another. Eating health fats like Omega 3s helps. And engaging in moderate exercise, getting good sleep, and having good connection to family, friends, and nature also help reduce inflammation in various ways. And of course avoid sugar and most refined carbohydrates -- as well as most food additives. Example link: https://www.health.harvard.edu/staying-healthy/foods-that-fi...
Except you can do all that (have always done that) and still be struck down with run-away inflammation, and without being some obvious genetic outlier.
What you are describing is nowhere near the cure-all that unsymptomatic bystanders assume it is.
You may also get hit by a car or get struck by lightning. Nothing is a guaranteed cure-all but what the GP describes is probably a good idea for a lot of people.
Well cerntainly a good idea to have a balanced healthy diet, taking daily amounts of baking soda is not to keep your self healthy, but rather to help those that have an abnormal autoimmune response.
For those with autoimmune disorders no amount of healthy diet is enough.