Digestive Health
Dr. John Briffa

Dr Briffa examines some of the digestive inadequacies that can lead to, or be mistaken for, food sensitivity - and suggests some natural ways of dealing with them.

Conventional medical wisdom dictates that before food is absorbed from the gut, it is first digested down to its smallest constituents. However, while sound in theory, it seems that this notion does not stand up in practice. In reality, partially digested food can breach the gut wall, where it has the potential to trigger unwanted reactions in the body. Failure to digest food properly is an obvious risk factor for food sensitivity, and many who are intolerant to one or more foods quite often are poor digesters.

The Process of Digestion

Digestion of food starts in the mouth. The very act of chewing stimulates the secretion of digestive juices lower down in the gut. Chewing also mixes food with an enzyme which starts the digestion of starchy foods such as bread, potatoes, rice and pasta. By breaking food up, chewing also increases the surface area available for contact with the digestive juices, allowing them to penetrate the food and do their digestive work.

Once swallowed, food makes its way to the stomach where acid starts the digestion of protein based foods such as meat, fish and dairy products.

Once food leaves the stomach, it passes into the small intestine. Here it is subjected to the action of digestive enzymes that continue the digestive process. Some of these are found in the wall of the gut itself, while some of these are secreted by a gland called the pancreas. Bile, secreted by the gallbladder, also works on the food and helps with the digestion of fat. The purpose of digestion is to break food up into pieces small enough to be absorbed through the gut wall into the blood stream.

Problems with Digestion

While most doctors and dieticians assume that food is generally only absorbed in a completely digested form, this does not appear to be true at all. In some individuals, the process of digestion can stall. This, coupled with a degree of leakiness in the gut wall, set up the potential for food sensitivity reactions.

Inadequate chewing is a common problem in poor digestion. Another potential issue is a lack of acid in the stomach. Symptoms that are suggestive of this include bloating, belching or burning immediately after meals. Other features of low stomach acid may include a feeling of food sticking in the upper abdomen, or that just a small quantity of food causes a feeling of fullness.

Stomach acid isn’t just important for the digestion of food, but also plays a critical role in the absorption of certain nutrients including minerals such as iron and vitamins such as B12 and folic acid. All of these nutrients are essential for healthy red blood cell formation. As a result, long standing low acid secretion can lead to a problem with anaemia. Anaemia that tends not to respond to supplementation with iron or other nutrients is quite often related to low stomach acid.

Apart from indigestion, other symptoms which suggest low acid secretion include weak nails and/or poor hair quality. Nails which are brittle or tend to flake and peel is quite a common symptoms in women with low stomach acid. Men, even though their stomach acid secretion is low, tend not to suffer from weak nails. Another common symptom in women is hair that is thin, brittle and tends not to grow well.

Another potential cause of poor digestion and food sensitivity is a lack of the digestive enzymes normally present in the small intestine. Some of these enzymes are naturally present in the lining of the digestive tract, but most are secreted by the pancreas and enter the small intestine via a small tube known as the pancreatic duct. Low levels of digestive enzymes can also provoke feelings of fullness after meals, and also symptoms such as indigestion, bloating, belching and wind. However, whereas individuals with low stomach acidity tend to get their symptoms immediately after meals, individuals with an enzyme problem will only normally start to get symptoms 1–3 hours after the meal.

Medical tests for digestion

The most widely used test for digestion measures stomach acidity through a technique known as radiotelemetry. Here, the subject swallows a capsule on a thin piece of string. The capsule, known as a Heidelberg capsule, contains a pH sensitive electrode. Once in the stomach, the capsule transmits a reading of the stomach acidity which can then be detected by a sensing device held over the stomach on the skin surface. This test is good and relatively inexpensive. However, it is not considered to be part of mainstream medicine, and your doctor is unlikely to have heard of it. The test (called the Gastrogram) is available at Biolab Laboratory in London (020 7636 5959), though it can only be ordered by a practitioner.

While the test described above can be a very good way to diagnose a low acid problem, a simple home test can help to identify this condition. A level teaspoon of bicarbonate of soda should be dissolved in some water and drunk on an empty stomach. If sufficient quantities of acid are present in the stomach, bicarbonate of soda is converted into gas, producing significant bloating and belching within 5 or 10 minutes of drinking the mix. Little or no belching is suspicious for low stomach acid.

Natural methods for improving digestion

A few simple strategies can be very effective in improving digestion if there seems to be a problem here.

1. Chew Food Thoroughly

Proper chewing is essential for proper digestion. As mentioned earlier, chewing stimulates the secretion of acid and digestive enzymes. Chewing also mixes food with saliva which contains an enzyme which itself starts the digestion of starchy foods such as bread, potatoes, rice and pasta. And perhaps most importantly of all, chewing breaks food up, massively increasing the surface area available for contact with the digestive juices. This increases the efficiency of digestion by giving digestive enzymes the opportunity to penetrate the food and do the digestive work. Each mouthful should be chewed to a cream before swallowing.

2. Avoid big meals

The larger the meal, the larger the load on the digestive system. Small, frequent meals ease the burden on the digestive system and increase the likelihood of full and complete digestion.

3. Avoid drinking with meals

Some people tend to drink quite a lot of fluid with meals and believe that this can only help to ‘wash food down’. The reality is quite the reverse. Drinking with meals dilutes the acid and enzymes which do the digestive work, and does nothing to help the process of digestion. In the main part, drinking should be done between meals, not at meal time.

4. Consider Food Combining

Foods are made up of several chemical constituents including proteins, starches, fats, vitamins, minerals, fibre and water. The common proteins in the diet can be found in animal products such as meat, fish, dairy products and eggs. The common starches in the diet are bread, rice, pasta, cereals and potatoes. Proteins and starches are very different chemically, and are digested by different enzymes in the gut. In addition, proteins are initially digested in acid, while starches are digested in alkali (quite the opposite). Some individual’s digestive systems are unable to cope with protein/starch combinations, and this can lead to impaired digestion.

The principle of food combining theory is to avoid mixing protein (e.g. meat, fish, eggs) and starch (e.g. bread, potatoes, rice, pasta) at the same meal. This means eating either protein or starch, and combining it with a food which is classified as ‘neutral’ (e.g. non-starchy vegetables).

Supplements for over-coming food sensitivity

Supplements of hydrochloric acid (HCl) taken in capsule form can certainly assist in the digestive process in individuals who have low or no stomach acid. Part of the action of hydrochloric acid is to convert an inactive substance called pepsinogen, into an active enzyme called pepsin. The function of pepsin is to start the digestion of protein food molecules. Acid supplements are therefore best combined with pepsin for maximum potency. Acid supplements should be taken before meals. Because acid supplements may worsen or possibly even cause inflammation or ulcers in the stomach, they should only be used under the instruction of a suitably qualified doctor.

A good alternative to acid capsules are supplements of digestive enzymes. A good digestive enzyme supplement will normally contain a range of enzymes each of which is responsible for digesting a certain food type. Examples of such enzymes include:

Protease – for the digestion of protein

Bromelain – for the digestion of protein

Amylase – for the digestion of starch

Sucrase- for the digestion of sugar (sucrose)

Cellulase – for the digestion of cellulose in plant matter

Lactase – for the digestion of lactose (milk sugar)

Lipase – for the digestion of fat

Maltase – for the digestion of maltose (a form of sugar found in some grains and made naturally in the gut)

Digestive enzyme use should be avoided in cases of gastritis (inflammation of the stomach lining) and/or ulceration, but otherwise seem quite safe to use. 1 or 2 capsules should be taken after each main meal.

Dr John Briffa is a Nutritional Physician, the Observer’s nutrition columnist and author of Ultimate Health – 12 Keys to Abundant Health and Happiness (Michael Joseph) from which this piece was extracted. He can be contacted via his website at www.drbriffa.com


Click here for more articles on digestive conditions

First Published in 2003

Back to top

If you found this article interesting, you will find many more general articles and research reports on coeliac disease here, and lots of information on the management of coeliac disease here.
You can also find articles and research reports on gluten intolerance here and articles on a wide range of other digestive conditions here.

For hundreds of gluten free foods see our freefrom food section here, and for nearly 800 gluten-free recipes see here.

And if you would like to get our FREE fortnightly e-newsletter with new products, recipes, articles and all the latest news from the allergy and freefrom world, just sign up here.