Brief Answer:
Only lower back pain can be caused by over weight.

Detailed Answer:
Hi,
As per your complain it seems that you are suffering from excess intestinal gas formation that is leading to excess formation of intestinal gas as well as there are abdominal discomfort, bloating and pain.

It can occur due to number of causes like:
-Intake of certain foods.
-Eating too fast that can entrap excess of air.
-Lactose intolerance, excess intake of dairy.
-Diseases like Crohn's Disease.
-Bacterial infection in intestines.
-Constipation.
-Frequent chewing of chewing gums and sucking candies.
-Excess intake of dairy etc.
-overweight can only be responsible for back pain.
While other problems are due to gastrology events and are chronic therefore a proper consult with a speciality a Gastroenterology should be done/general query are not meant for speciality and get a thorough evaluation done and he can advise you investigations like endoscopy, blood tests, stool culture, etc. to confirm the diagnosis and treatment of the cause can resolve the problem.
-Start doing regular workouts it is a good practice.
-You should also take walk after meals.
-You should take small portions of food every 2 hours.
-Avoid heavy and large fatty meals.
-You should also limit intake of frizzy drinks, smoking and excess chewing gums.
-You can take Simethicone as it help in reducing intestinal gas.
-Activated charcoal pills can be helpful.
-Drink sufficient water.
-chew your food slowly and properly.
-Try running on treas mill to loss weight.
-Elevated walking would be helpful.
Take prebiotics and probiotics daily.
Take vsl#3 daily once.

Hope I have answered your query. Let me know if I can assist you further.

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