Today, our food arrives to our table by a variety of means and methods. In this day and age it is a very difficult task indeed to work out the exact 'life' our food has led before it reaches us and how good a food it actually is when it gets to us.
For instance, not that many years ago, food was mostly grown, produced and consumed within either a short distance or had to be 'transformed' into a form that would survive longer in storage (i.e. jams, pickles, dry cured, salted, etc).
Nowadays, technology and science provides many ways of overcoming the restrictions of 'locality' of production and consumption. For instance the invention of powered refrigeration has allowed foods to be stored and transported over great distances in large volumes. Also a better understanding of how food 'goes off' has led to the use of chemicals and advanced packaging techniques (i.e. vacuum packed, tinning, etc).
What really needs to be remembered these days is that the food business is a multi-billion dollar world-wide business, where the profit margins are 'squeezed' all the way through the supply chain. Time literally is money and anything which can be done to make foods last longer is literally profit in hand, as by giving more time for transportation to two things occur:
Note: None of this is directly related to the actually 'quality' of the food obtained, the aim is not to get higher quality food, rather to get the same food cheaper...
So how does this all impact you and how does it relate to Food toxicity? Read on..
In general, the level of environmental contaminants in our food complies with the limits recommended by government health authorities. However, because of the uncertainty in establishing exactly what is a safe level for many of these contaminants, it is in the interests of our general health to consume as wide a variety of foods as possible. By doing this, the chances of eating large amounts of a contaminated food are minimized. Continued and extensive surveillance and control are needed.
Of course the level of surveillance and control are not a universal constant, and this is where the toxin problem 'creeps in'; food sourced from other markets might not consistently apply the same controls as expected in the local market. Also the surveillance might not be looking for the right things or told to ignore things that are becoming known as problems.
The common environmental contaminants of greatest concern in food are the so-called 'heavy metals', most notably cadmium, lead and mercury.
Almost all of the mercury found in food occurs in seafood.
A dramatic instance of mercury poisoning occurred in the Minimata Bay area in Japan. Fish and shellfish that were heavily contaminated by industrial waste caused poisoning in many of the people who ate them, resulting in damage to the central nervous system and in some instances death.
Surveys of the levels of mercury and other heavy metals in food are regularly carried out and have shown that generally the levels are below the maximum amounts permitted by health authorities. Occasionally, higher levels are detected and the food withdrawn from sale.
Lead occurs widely in the environment and it can enter our bodies through drinking water (either from source or via lead piping) and the air we breathe, as well as through food.
Children are the group at greatest risk, because even at levels below those that produce the usual signs of poisoning, lead can cause behavioural abnormalities. The levels of lead that cause these effects are uncertain so it is difficult to estimate what amount is 'safe'. In some areas, particularly where there is heavy lead pollution in the air from leaded petrol, lead levels may be hazardous for children.
Cadmium is present at very low levels in a wide variety of foods. Poisoning due to cadmium in food is rare. The upper 'acceptable' limit for cadmium in food recommended by the WHO (World Health Organization) is generally complied with. The kidneys of animals are generally higher in cadmium than are other foods. Contamination of rice, soya bean and seafood with cadmium from local industrial and mining operations has caused cadmium poisoning.
Two very persistent environmental contaminants are the pesticide DDT and PCBs (polychlorinated biphenyls), which have been used in electrical transformers, plastics and paints. DDT and PCBs are not easily degraded in the environment and can concentrate in the fatty tissues of many organisms as they move up the food chain. Recent surveys in Australia have not detected the presence of PCBs in food. DDT has been found in many foods but the amounts are such that the total daily intake of DDT is within the acceptable' upper limit recommended by the WHO.
The notion that 'natural' food may be harmful is not widely understood. The terms 'health', ‘organic', 'natural', 'unprocessed', 'no added chemicals' when applied to food suggest that the food is safer or more nutritious than its conventional counterpart but this is might not be true. All food is entirely made up of chemicals. In addition to well-known nutrients such as carbohydrate, fat, protein and water, food contains many other substances.
Any substance in a food may have a degree of toxicity or 'poisonousness', whether it is natural, deliberately added, or a contaminant. There is nothing special about natural chemicals in food and no distinction should be made between natural and other substances when deciding if a food is likely to be hazardous. For example, a potato contains a number of poisonous substances such as nitrate, arsenic and solanine but in the amounts in which potatoes are normally eaten these natural substances are not hazardous. For this reason it is important not to consume large amounts of a small number of foods, as in some faddist diets, but to consume a wide variety of foods. This not only minimizes the amount of a particular potentially hazardous substance but also ensures that a range of essential nutrients are consumed.
Herbal teas have become popular with an increasing number of people. Herbal and 'bush' teas contain a large number of different components, many of which have not yet been assessed for safety. Some teas can lead to disturbing effects. Tea made from the South Pacific kava plant has been associated with impaired breathing, vision and hearing, and other symptoms. Comfrey and tea made from the roots of sassafras contain substances that have caused cancer in laboratory animals. In addition, some teas can interfere with the therapeutic value of some drugs that are taken at the same time. Heavy consumption of these teas is not to be recommended.
It must be remembered that heavily processed food only really exists to do the following:
In the last few years, gluten intolerance has become more and more common; now the problem with this is two fold:
This presents a potential decision problem; the first case means nothing has changed with the food as such, just our ability to diagnose (or willingness to do so). The second indicates something fundamental has happened. My gut (no pun indicated) says a mixture of both, as its very hard to find all sorts of food without gluten in it. Which given its from a specific seed family means most of the population are being exposed to a common ingredient, a situation which is highly artificial.
The only good news is that with the increased awareness has come an increased availability of Gluten Free foods, although at a price.