I am not a qualified medical doctor. But I know many people have this stomach problem. I reproduced it for your benefit. You may like to read how do I avoid stomach problem at the end of this article.    

An upset tummy is a nuisance. But when it becomes chronic, ongoing stomach distress can deeply affect one's quality of life. Very often, this is due to gastritis, an inflammation of the stomach lining which has become increasingly common. Typically, there are two causes of gastritis: the overuse of nonsteroidal anti-inflammatories (NSAIDS) like ibuprofen, and also, an infection by the bacterial species Helicobacter Pylori - a bacteria that is present in almost 50 percent of the countries of the world. In some cases, this little bug can attack and break down the stomach lining, causing gastritis and may potentially lead to stomach ulcers. 

Nevertheless, these two culprits aren't always responsible for the gastritis suffered by many. There may also be other etiologist of chronic gut pain and discomfort. This is what is actually happening in the stomach: the stomach lining is programmed to produce stomach acid and the enzyme pepsin to break down our food. But when the lining is somehow compromised, acid and pepsin are no longer produced in adequate quantities. Injury to the stomach lining results in the formation of less mucus on the surface of the lining to protect it. So, even though less acid and enzymes are being released, there still is less protection to prevent irritation of the stomach lining.

Once irritated, many symptoms can arise. You may experience cramping, pain, bloating and gas and though less likely, you may also experience vomiting, fatigue, nausea and feeling of heaviness. These symptoms can become regular and can increase in frequency. Keep in mind this chart:

But if your gastritis is not caused by nonsteroidal anti-inflammatory drugs, what could be causing you stomach problems? Most of the time, the culprit is food. Certain foods create a less than desirable environment in the stomach - in particular soy, corn, highly processed foods, coffee, energy drinks and trans fats. These foods do not promote an optimal environment inside the gut and can cause severe irritation in the stomach tissue. Stay away from these foods:

The good news is that not all food is bad. There are foods that can improve your gastritis, healing and regenerating a proper balance within the stomach. Anti-oxidant rich foods with an alkaline PH are ideal - primarily ginger, beet juice, leafy vegetables and yogurt. Here are more foods you should favour:

How do I avoid stomach problem?

As soon as I wake up in the morning, I drink 2 glasses of water and a cup of coffee. I eat about a quarter- half a pineapple on an empty stomach. I do not eat anything until lunch time. As a result, I do not have any constipation or any sickness in the last 20 or more years. I am 88 years old. I am physically fit and mentally sound. I can walk without a walking stick and I can write this article.