Do you know where your food comes from and how it is grown? In traditional farming societies, people have an intimate connection with the food they grow and eat but for urban populations, food generally comes from a shop shelf. We can take a lot of trouble to choose a good diet and prepare interesting recipes, but good chefs know that however skilled a cook you are, you cannot prepare a good meal from poor food ingredients.

Nutrition and health

We live in a world where technology is so advanced that communications, complex industrial processes and household chores are achieved by the flick of a switch, yet the majority of people in the world suffer from malnutrition. The reasons vary: insufficient food, insufficient income to pay for food, poor dietary choices, but a further reason is less often acknowledged: poor food quality.

Much of the food consumed in more affluent societies is deficient in quality. It does not contain sufficient essential oils, complex sugars, vitamins and complex proteins with the right balance of essential amino acids to keep us healthy. Most of the ways in which food is assessed for quality do not show up these deficiencies, and we cannot always rely on our taste. We can be fooled into eating poor quality food through artificial flavouring additives.

There is increasing evidence that our food and diet contribute to ill-health. Obesity, diabetes, cancer, cardiovascular disease, eczema, asthma, food allergies – the list goes on and on. Nutrition has been found to affect mental and emotional states as well as physical health.

We are recommended to eat more fresh fruit and vegetables and wholefoods. As we have seen, the Five-a-Day campaign encourages people to eat at least five servings of fruit and vegetables a day. But some medical doctors and nutritionists advocate nutrient supplementation because the nutrients in fruit and vegetables currently available are insufficient to protect against infertility, learning disabilities and a range of illnesses. This is not a new concern. In the 1930s a dentist, Dr Weston Price, thought the tooth decay he found in people’s teeth related to their diet. He compared the ‘Western’ diet with those of Eskimos and various African and Indonesian people who still ate traditional diets. People eating traditional diets were much healthier, with little tooth decay, and their food contained at least four times as much calcium, other minerals and water-soluble vitamins and ten times the amount of fat-soluble vitamins than Western diets of that time (Price 1939, pp.275, 276). Since that time, comparison of nutrient tables between 1936 and 1986 has shown significant reductions in the average levels of calcium, magnesium, copper and sodium in vegetables, and of magnesium, iron, copper and potassium in fruits (Meyer 1997).

There could be several reasons for this decline. Maybe plant breeders have inadvertently bred less nutritious strains through focusing on other attributes such as yields, fast growth and pest and disease resistance. A major problem is that plants are forced to grow too quickly without all the elements and energies needed for balanced growth. Genetic modification is promoted as the way to increase nutritional content of food, regardless of the dangers to our health and the environment. But some farmers have shown that food nutrient content can be greatly improved through working with nature rather than against it.

Most of us are well aware that we need to regularly consume plenty of vitamins and minerals and many people try a variety of diets. Even if we do manage to find the right diet for our individual type, and eat a well-balanced diet, with plenty of fresh home-grown or organic labelled fruit and vegetables, and reduce intake of harmful fats, sugar and processed food, it may not solve our health problems. Many people find they need to take vitamin supplements and other health foods to maintain energy levels and health. How many people do you meet who are really bursting with energy, and whose eyes are sparkling with health and vitality?

The situation is serious, it is time that we take charge of what we eat and learn to distinguish good quality food through using our senses of taste, smell and sight, and seek good quality food rather than fake food.

I have an eighteen month old grand-daughter who I visit as often as I can. It has been fascinating watching her introduction to eating food and what she enjoys and doesn’t like. She enjoys most of her meals and particularly likes green vegetables and slices of orange picked fresh from the tree. My daughter has difficulty finding her foods suitable for breakfast, with most of the breakfast cereals containing a lot of refined sugar and artificial flavourings. We had a discussion about buying organic cow’s milk. My daughter was not convinced that the benefits from it would be sufficient to warrant paying over twice as much for organic milk compared to the conventional milk. When I see my grand-daughter blissfully drinking her bottle of milk, I wonder about the farms the milk came from and what difference it might make to her growing body whether it was organic or not.

I think this is a dilemma many of us face: what are the benefits of organic food, and is it worth paying more for? We know there is a reduced risk of pesticide and other chemical contamination of organic food, and that it is grown with more care for the environment, but what about nutritional quality? Many scientific trials have compared nutrient quality of conventional and organically grown food. Overall their results have been inconsistent and inconclusive, although many of the tests have shown fewer nitrates, more vitamin C and some minerals in organic food (Heaton 2002). Some recent trials have found that organically grown fruits and vegetables have higher antioxidant activity (Ellis et al. 2006) and that organic milk contains more essential oils than non-organic milk (Mitchell et al. 2007).

Food production methods affect product quality and taste

Nutritionists recommend that everyone should consume several servings of fruit and vegetables each day. But no-one seems to mention the huge variations in nutrient content you can encounter in fruit and vegetables. The USDA nutrient database (USDA 2011) shows average calcium content of iceberg type lettuce leaves to be 18 mg, and iron content 0.4 mg, per 100g fresh weight. Corresponding figures for loose-leaf type are 40 mg and 0.9 mg. That is a big difference, and note that these are average figures and individual lettuces would vary a lot more than that!

Basic soil type and quality has a large effect on nutritional quality of vegetables grown in the soil. Another major reason for differences and decline in quality is the way food is grown, which is a focus of this book. Many trials have shown differences in nutrient content between lettuces of the same type, and of other vegetable types, grown in soil managed in different ways.

Let’s think about the different ways of producing food. Are you aware that many of the leaf lettuces and tomatoes in the supermarkets are grown hydroponically in huge greenhouses? Lettuces grown quickly in nutrient solution in an artificially lighted glasshouse may contain more of some chemical nutrients than those grown in old-fashioned composted soil in the back garden, but they have insufficient exposure to sunlight to build the complex proteins and oils we need. I would like you to consider other questions which will be further discussed in this book. For example: do you think home-grown tomatoes generally taste better? Taste can be a good guide to nutritional quality.

Have you had the experience of broccoli quickly turning to a bad-smelling mush when cooked? This broccoli has been grown quickly with a lot of fertiliser, so has a high water content. It may also be bitter, containing high levels of nitrates from nitrogen fertilisers. When a plant takes up nitrogen it is transported from the roots to the leaves. The leaves use sunlight to convert the nitrates to protein. If large quantities of nitrates are absorbed by the roots, they are likely to be deposited in the leaves more quickly than the leaves can convert them. Some of the nitrates remain in the leaves and in the broccoli heads, making them bitter. The bitter taste and low protein content of such vegetables is not the only problem: nitrates can be converted to nitrites in our bodies. High levels of nitrites can interfere with the transport of oxygen with serious health effects.

Many of the fruits and vegetables we buy can contain high levels of nitrates. A dark, bluish green in leafy vegetables is an indication of high nitrate content. No wonder many children reject vegetables – they often taste bitter because of their nitrate content.

Large scale ‘factory farming’ methods of food production

Fruit and vegetables with high levels of water and nitrates are a consequence of modern farming methods that use soluble nitrogenous fertilisers to grow large plants quickly. Food production has become very large scale and industrialised to keep production costs low. Crops are grown quickly and cheaply by applying large quantities of soluble fertilisers such as urea and superphosphate. The plants have to take up these soluble fertilisers when they take up water. Soil conditions are created in which plants are unable to absorb other nutrients such as copper and iron. The plants are not supplied all the different trace elements and energies needed for a healthy plant and the food produced by them is deficient in these minerals.

Unhealthy plants easily succumb to pests and fungal disease. To prevent this happening the plants are sprayed with pesticides and fungicides, traces of which may remain in the harvested food products. Even the low levels of pesticides that food authorities consider ‘safe’ adversely affect many people. Hormone disruption and infertility have been linked to specific insecticides and herbicides (Walsh et al. 2000). Crops such as celery and apples are generally sprayed many times with pesticides and onions are sprayed frequently with herbicides.

This type of farming has the advantage of enabling fast, large-scale production for large urban populations at costs low enough for people to afford. These production methods do not always lead to the problems discussed above, and poor quality food. Some good farmers with high quality soil grow high quality produce on a large scale. But large-scale distribution organisation may mean that produce such as milk and grain is collected together from many farms for transport and processing. The good quality is mixed with poor quality and the end buyer has no knowledge or control over the quality of food they buy.

The animals that produce the milk and meat we eat may also have suffered from eating pasture and grain crops grown with too much fertiliser and chemicals. Cattle have a different digestion system to ours. It is a longer process, including fermentation in the rumen stomach. Soft, fast-grown grass and maize corn do not provide sufficient fibre to enable proper fermentation, so the cattle are not healthy and cannot produce good food.

Many farm animals are kept in buildings with little or no access to pasture, soil and sunshine. This is not only cruel and unnatural, but can lead to poor quality food. Chickens and pigs eat grass and scratch in the soil when they have access to it. They pick up a large quantity of beetles, worms and other soil organisms, which are a good source of protein for them. The soil they ingest contains natural antibiotics which keep them healthy. When kept on concrete floors they would succumb to disease if not fed artificial antibiotics.

A DVD titled Food.Inc. (Schlosser & Pollan 2008), that shows how most food in the USA is grown, has been circulating around the world. If you have seen it, you are likely to have been as disgusted as I was to see how much of the chicken meat and hamburgers consumed in the USA are produced. How can chickens crowded into barns, so fat they cannot walk and cattle fed an unnatural diet of maize corn, knee deep in manure, produce food fit for us to eat?

We need more information about what are the alternatives to this type of production and what difference they make. Many people experience food grown by biological and organic methods as providing more wellbeing, even though scientific studies have not shown much difference in nutrient content compared to mainstream food. Chapter 3 discusses how the nutrients in food are measured and whether they can show the full nutritional value of food. With so many people less healthy than they would like to be, isn’t it time we took charge of our own health and find out how to recognise and source good quality food?