We are what we eat. Most of us would agree that in the long term, good health is sustainable only with good nutrition.

However, if we cannot process and absorb our food efficiently, even the best diet is of little use. It is more accurate to say we are what we absorb.

If one of the organs malfunctions or the conveyerbelt system is interrupted, there is an immediate knockon effect on the entire system.

In time, poor digestion and absorption may be responsible for chronic illnesses.

The digestive process often goes wrong from the start. Prone to overeating and bolting down our food without a thought to what happens next, we are encouraged to reach for antacid medication when indigestion strikes.

Antacids may relieve the problem but, alarmingly, recent research from the University of Vienna suggest they may be responsible for food allergies.

Another study found mice given the popular acid-reducing medicines ranitidine and omeprazole frequently develop allergic symptoms.

These reports make a lot of sense. Gastric juice is strong stuff and the stomach should produce one to two litres per day. It sterilises food, reducing our exposure to undesirable bacteria.

The acid also helps to free minerals such as calcium, iron and zinc from our food, an important first step towards preventing anaemia or osteoporosis.

Gastric acid is crucial for the digestion of proteins, stimulates the pancreas to secrete enzymes and the gallbladder to release bile.

If you don't make enough stomach acid to digest your food properly, problems are to be expected.

Common symptoms are bad breath, bloating, belching, burning and flatulence after meals and a sense of fullness after eating.

Other symptoms may include nausea, diarrhoea, constipation and undigested food in stools. And, if the gut is continuously presented with larger protein molecules that haven't been processed properly, allergies may result.

Therefore, Nutritional Therapists routinely evaluate your digestive capacity and, if necessary, recommend digestive aids that work with your stomach to support the process.

Increasing age, nutrient deficiencies, certain bacteria, diet and drugs all contribute to low acid levels, which is a surprisingly common problem.

The growing popularity of the Atkins Diet virtually guarantees low gastric acidity in those poor tummies unused to large amounts of protein.

People with low stomach acid often mistakenly believe they suffer from excessive stomach acid and rely on indigestion pills.

But they may not realise these reduce acid levels even further, undermining digestion and making the situation worse in the long term.

GlaxoSmithKline (Zantac, Settlers), and Roche Healthcare (Rennie) insist their pills are perfectly safe, suggesting that if acid-lowering treatments caused problems, there would have been some evidence of it by now.

With allergies at record levels, there is ample evidence, if you care to look for it.

Will it prevent drug companies from pushing allergy-inducing antacids down our throats? Somehow, I doubt it.

Martina Watts is a qualified Nutritional Therapist at the Crescent Clinic of Complementary Medicine, Brighton (call 01273 202221), and the Dolphin House Clinic, Brighton (call 01273 324790), or visit www.thehealthbank.co.uk