Acidity is related to heart burn and gas formation in stomach. In acidity, there is a movement of gastric juices from the stomach into the lower esophagus (food pipe). This condition mainly arises when acidic contents in stomach (hydrochloric acid) move upward into the esophagus and making it dysfunctional. Also known as pyrosis or burning or painful sensation in the esophagus.
Acidity leads to the sour, painful or burning sensation in the stomach and chest region is termed as heartburn. Its other symptoms include dyspepsia, formation of the ulcers, belching, nausea, bitter taste in mouth, feeling of vomiting and loss of appetite.
Acidity is the cause of surplus secretion of acid by the gastric glands of the stomach. Our stomach secretes an acid, which is necessary for the digestive process. This acid, in turn, produces various digestive enzymes, like pepsin, which help in the breaking complex food particles into elements that can be easily digested by the body. When there secretion of acid is more than necessary, it results in the feeling of immense heartburn, along with a sensation of inflammation in the throat. This condition is commonly known as acidity.

HOME REMEDIES
Take 150mg fresh lime juice, 4 table spoon of honey and 1 liter of water. Mix the three things well; you can ¼ part of it in the morning and same amount in the evening.
Take one cup of boil water. Add one tablespoon of aniseed (saunf) in it and leave overnight. Strain the water in the morning, add one tsp of honey in it. Take this remedy 3-4 times a day.
Regular practice of in taking of one to two glass of water, in early morning is healthy habit and helpful in acidity control.
Excessive acidity can be dispelled by using hot compresses of Chamomile or Lavender (l0 drops) in a bowl of water and then used or add 1-2 drops of oils of either of these oils to base oil and then applied over whole abdomen.
Chew the leaves of Tulsi (basil plant) which is helpful in controlling nausea, gas and acidity.
Take equal portions of ginger and coriander to get relief from acidity.
Drink a glass of cold milk for quick relief of heartburn and acidity.
Take two tablespoon of honey with two tablespoon of natural cidar vinegar before meal.
Mix a tsp of Slippery Elm (Ulmus Fulva) in water or take it in tablets form. It soothes the inflamed stomach.
Take dried blossom of tulsi, rind of the neem tree, black pepper and peepal in even quantity and grind them to powder form. Take 3 gms of this powder every morning and evening with plain water. All the acidic effect of the body shall pass out with urine and sweat.
Take 1 or 2 raw potato and wash them well. Do not peel, instead, cut them into pieces and churn them. Drink the juice immediately or mix it with some other juice for taste.
Drink 1-2 glasses of water early morning to keep yourself healthy and free from acidity.
Amla (Indian gooseberry) is also helpful in curing acidity. It can also be taken with haritaki (chebulic myroblan).
Squeeze the juice of a whole orange and mix it with roasted cumin seeds add some rock salt.
Prepare tea using chamomile tea. Intake this tea after meals. This would relieve a person from esophageal irritation.
Taking 2 tablespoonfuls of Isabgol in milk after every meal is also very beneficial in eliminating acidity.
Drinking coconut water 4-5 times a day is an effective natural treatment for acidity.
Take Harad (Terminalia chebula) after meal. It is also effective natural remedy for heartburn.
Eat fruits and vegetables rich in fibers to help proper digestion.
Mint is natural remedy in treating acidity. It can be taken after meals either directly or in juice form.
Have a glass of cabbage juice everyday, in order to avoid acid formation and the resultant acidity.
Eating cucumber, watermelon, papaya and banana are helpful in reducing the acidity.
Half glass of butter milk with one tablespoon of coriander is also effective in reducing the acidity.
Acquire one piece of clove and suck on it gradually.
Jaggery (gur) is best home remedy for acidity. Take small piece of it in your mouth and suck it slowly. Repeat this several times.
Eating yogurt provides immediate relief from acidity.
Lemon is the best for acidity as it helps in treating heartburn. Cut a lemon into thin strips and dip in salt or take lemon juice with salt. Take it before meals to prevent heartburn.
Make a fine powder of ginger powder, black pepper, dried mint leaves, asafetida (hing), anise seeds, coriander seeds, cumin, fennel and common salt taken equally. Take one teaspoon of this powder with water, twice a day after meals.
Try and include a small amount of garlic in your diet.
Almonds are also a good source for relieving the heartburn and acidity. Eat several almonds when heartburn symptoms persist.

The causes of acidity can be excessive smoking and drinking alcohol, gastro duodenal (peptic) ulcer, hyper secretion of hydrochloric acid, reflux of gastric acid, not eating on time, empty stomach for a long time or skipping breakfast, pregnancy, eating fried and spicy food regularly.

Acidity can be prevented by avoiding the known causative factors like alcohol consumption, spicy foods, drugs like NSAID's, steroids etc. Regular eating habits and a healthy diet can prevent acidity. Avoid drinking water during and soon after meals as this dilutes the gastric juices necessary for digestion and prolongs the process. Eat green and leafy vegetables. Try to avoid having late meals just before bed time. There should always be an interval of at least two hours between your last meal and bed time.