Stomach

From the mouth, food is swallowed down a long muscular tube, the esophagus, into the stomach. The two most important aspects of digestion here are the physical mixing of food and the chemical action of hydrochloric acid, which is produced in certain cells in the stomach. Food is mixed with the help of three layers of smooth muscle that make up the stomach. This is the reason you may feel and hear normal noises from your gut—there’s a lot of churning going on there, especially after a meal. It’s much like your washing machine.

When food enters the stomach, hydrochloric acid is normally secreted and is vital to proper digestion, helping to make nutrients from foods available for absorption. This natural acid stimulates other digestive enzymes, such as pepsin for the breakdown of protein. Hydrochloric acid helps make vitamins, minerals, and other nutrients more absorbable. It also kills bacteria, viruses, parasites, and other potentially harmful invaders that commonly enter through almost all foods. Reducing your hydrochloric acid with antacids can be detrimental for many reasons. First, protein digestion may be impaired and you may not absorb the much-needed amino acids. It can trigger immune reactions if undigested (whole proteins) are absorbed, one common cause of allergies. Hydrochloric acid also triggers digestive enzymes in the small intestines and pancreas, areas that complete the digestive process and prepare nutrients for absorption.

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Taking antacids is not the only way to reduce levels of hydrochloric acid. As we age, there is often a lowering level of normal stomach acid, and stress can do the same. Excess stress typically reduces the stomach’s acid, despite the common notion that stress overproduces acid—much of this myth comes from the marketing of very popular antacids. Fewer people than one might think over-produce hydrochloric acid under stress. This usually happens between meals, where most have learned that eating a small amount of food reduces or eliminates the discomfort caused by too much acid.

Drinking liquids with meals may also dilute stomach acid and enzymes resulting in less-efficient digestion. Drink all your water between meals, avoiding it about twenty minutes before and an hour or more after eating. Soda, milk, sports drinks, fruit juice, and other liquids are not part of a healthy diet and as such should be avoided. An exception to drinking liquids with meals is wine, which may be consumed with meals as it can help digestion.

For those with inadequate hydrochloric acid production, supplements containing betaine hydrochloride (a solid which turns to hydrochloric acid when swallowed) can be very helpful. Common symptoms in people with low levels of normal stomach acid include belching and bloating after meals (especially with protein), bad breath, loss of appetite, and large amounts of foul-smelling gas. Those with reduced acid can develop abnormal fermentation in the stomach that produces other acids that are irritating, especially if they go upward into the esophagus, causing a burning feeling.

A common condition called GERD—gastroesophageal reflux—has become a frequently diagnosed problem. Drugs to treat the symptoms are among the biggest sellers, yet people still have the symptoms. In true cases of GERD, stomach contents back up into the esophagus, causing irritation, with symptoms occurring mostly after meals, or when lying down or bending over with the head below the waist. In severe cases, ulceration can occur in the esophagus. Most people have less serious but sometimes very uncomfortable symptoms associated with bloating due to gas. This often comes from eating starchy or processed carbohydrates, especially at the same time as eating dense proteins, overeating, and other causes of gas. Reducing or eliminating refined carbohydrates often eliminates the symptoms of GERD. In some individuals, eliminating lactose from dairy can do the same (lactose is a sugar that requires digestion). In other cases, poor stomach digestion, often from not enough stomach acid, causes GERD.