Brief Answer:
You need to change your lifestyle and modify your diet

Detailed Answer:
Thanks for asking on HealthcareMagic.

I have gone carefully through your query and understand your concerns. However, I do not suppose that you need to get anxious. Digestion involves chemical reactions and such reactions can be exothermic (when heat is produced during such reactions). This is responsible for your stomach turning hot. I understand that might be uncomfortable but tests will still yield normal results as it is just a part of how your body works. It is possible that the body is having difficulties in digesting and is therefore pouring additional stuff to digest it. But in that case you would need to take care of what you eat. You need to ensure a good amount of fiber intake if you are to deal with this problem.

Fiber rich food items include:
* Apples, pears, parsnip, berries, raspberries, kumquats, guavas, squash, oranges, passion fuit, avocado, blackberries, pomogranate, currants, persimmons, kiwi fruits, figs, bananas, blueberries, cherries, apricots, strawberries, tangerines, papaya, mangoes, pineapple, plums, litchi, grapes, watermelon
* Broccoli, cauliflower, cabbage, lettuce, brussels sprout, carrots, leafy vegetables and spinach, amaranth, artichokes, green peas, collard greens, XXXXXXX sweet potato, okra, fennel, eggplant/brinjal, sweetcorn, beets, turnip, asparagus, onions
* Legumes, beans, lentils, chickpeas, celery, soybean, navy beans, cranberry beans, french beans
* Whole grains, quinoa, brown rice, millets and oats, squash and pumpkin seeds, seasame seeds, dried coconut, almonds,
* Mushrooms
* Flax seeds, chia seeds, corn XXXXXXX

In order to relieve yourself, you also need to do the following:
* Avoid spicy food. Take small but frequent meals. Avoid long gaps between meals.
* Avoid alcohol intake (if it a part of your habit).
* Take Prilosec (omeprazole) once daily before breakfast.
* You may take fiber supplements like isabgol/psyllium husk or senna. I have already suggested you to increase your dietary fiber intake.
* Regular morning walk and exercise to keep the bowel movements proper.
* Take curd or yogurt on daily basis. It contains beneficial bacteria and should help.
* Stress reduction has a very important role to play. Yoga and meditation should help.

Sitting, lying or walking will have no effect on the mentioned heat.

Let me know if I could help further.

Regards

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