Despite our food and living conditions being cleaner than ever before, certain illnesses such as allergies and eczema are on the increase. Could high hygiene levels be responsible for these health problems? And could food provide the solution? Hugh Westbrook investigates.

We live in a clean society as never before. Our houses and bodies are scrupulously washed, as is our food. When we survey our vegetables in the supermarket, it is sometimes hard to remember that when harvested they would have been covered with mud, such is their pristine condition. But while we live longer than ever before, many would say that we do not live healthier - certain diseases are on the increase, while many people live with chronic conditions that they seem unable to cure. Is there a connection between our current state of health and our food consumption?

One theory which has been gaining currency over the last few years is the so-called 'hygiene hypothesis'. This suggests that various cleanliness factors in our lifestyles are leading to certain health problems. Allergies, eczema and irritable bowel syndrome are particular conditions that have received attention from this notion.

The hygiene hypothesis

The theory is largely based on the notion that we need healthy bacteria in our gut in order to function properly. It suggests that the growth in theincreasing use of pesticides has killed off a large number of healthy organisms in the soil, meaning our food no longer has certain vital nutrients. In addition, the increase in our consumption of antibiotics has served to kill off a large amount of the healthy bacteria whichbacteria that we do have, while our lack of exposure to dirt from an early age no longer allows us to build up a strong immune system, leading to health problems. Anecdotal evidence from the third world countries where dirt is more prevalent suggests that certain health problems are less common there.

Although Tthis theory is still unproven, but if food is seen as being one of the causes of the problem, could food also be one of the solutions? Research into the relationship between what we eat and our health is growing all the time. The growth of functional foods has shown that eating for the positive benefits that food can bring is an increasingly important area for production. One area in particular which has shown growthparticular that has shown growth is probiotics, which are beneficial bacteria.

The benefits of good bacteria

Products with probiotics seek to replace missing beneficial bacteria in people's bodies, so thereby improving their health. While their role is also unproven, there is a growing body of evidence to support their positive effects. A recent British Journal of Nutrition supplement presented a number of papers from a Yakult-sponsored probiotics conference held in September 2001. The research demonstrated that the consumption of probiotics can have positive effects.

Yakult is one of a number of companies selling fermented milk products for the beneficial bacteria whichbacteria that they contain. Company nutritionist Helen Killalla told just-food.com that she believed there was credence to the hygiene hypothesis, saying that we are exposed to lessfewer bacteria because everything is cleaner and we have smaller family sizes.

She said that recent studies have shown that babies with allergies and eczema have different gut flora to those without the problems, showing a direct correlation between bacteria and health conditions. She cited another study, which showed that children growing up around farm animals had lessfewer incidences of these conditions than those growing up with away from farm animals.

As for the effects of probiotics, she added that some studies have shown that giving them to children with allergies has seen an improvement in their health.

"We are trying to educate people into about beneficial bacteria, to get them into their daily routine and general diet," she added. "They are marketed as a general health product and are very much a food product and are sold as such."

Probiotics can also be ingested as a supplement. As well as cultures such as acidophilis, a number of supplement companies market products based on the notion that they are supplying what is missing from diet because of the pesticides used in soil. For example, US-based Garden of Life uses 'Homeostatic Soil Organisms' to deliver its probiotics in a bid to replicate benefits from soil which it claimssoil that it claims people no longer receive.

So is thereir universal support for the hygiene hypothesis? Britain's Food Standards Agency does not really agree and has recently launched a hygiene campaign aimed atto reducing instances of food-related illnesses caused by cleanliness problems.

An FSA spokesman told just-food.com that in the Agency's opinion, excessive hygiene does not cause problems. "People fall sick because of harmful bacteria, not because of good food hygiene. All the good bacteria which are needed live naturally in the gut. They are not destroyed by food hygiene, but can be disturbed by changes in diet, gut diseases and antibiotics, for example."

A food-based solution?

And therein lies with the problem with the hygiene hypothesis. Though it is an elegant and plausible explanation for many modern-day ills, it is unproven. And what would it have us do? We have to be careful about hygiene, the FSA and other similar bodies are absolutely right about that. We cannot judge just by eye sight whether some dirt is likely to be good or bad for us, so we will always err on the side of caution and cut the dirt out rather than include it in our diets.

In addition, people prefer their fruit and vegetables clean and ready for use - it is part of the modern lifestyle and they will not go back to having to wash everything. In fact, packaging with mud is a marketing statement in itself. We expect many of our organic vegetables to come with mud as in some strange way that seems to support their authenticity as something which is good for us. This in itself supports the notion that mud is somehow good for us. But we are now on a course whichcourse that is unlikely to change.

Therefore, probiotics will be one of the long-term answers to dealing with what is no longer in our diet. If it is the case that food production and presentation methods are denying our bodies vital, healthy bacteria, then it will also be through food-based solutions that we deal with the problem.