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Modern nutrition

The balancing act between science and experience 

Brigitte Neumann

Man needs food like air to live. But while breathing is a reflex, hunger signals that food intake is sensible, but what someone eats depends on the food supply and eating habits of the individual. They vary from age to age and from culture to culture, even from person to person.

Everybody has their favorite food. For example, spaghetti has long conquered our menu, spaghetti with pesto or with Bolognese is one of the most popular dishes not only among children, but there are also people who tend not to like spaghetti. Some foods trigger memories - both positive and negative - and often these associations remain burned in for life. It shapes dietary habits in early childhood - and changes only occur during a lifetime when a “re-education” takes place for a variety of reasons. This can happen through a changed offer, through the realization that one has to eat “healthier”, through diseases or also in adaptation to the budget for food. Changes in lifestyle also lead to a certain extent to changes in eating habits.

Most of all, however, the fundamental change from lack to abundance in our society, which goes hand in hand with an about-turn in nutrition science. Until the start of the 1960s the focus was on remedying deficiencies, but since then there has been an increasing tendency to fish out those foods that serve health abundance. With large campaigns and elaborate materials, institutes and institutions are trying to recommend healthy nutrition to the modern man of the 20th century for preventive-medical reasons.

It is no longer a matter of just being satisfied, but of the consumer wanting to choose the best food from the abundance of supply and producers, manufacturers and retailers fighting for their raison d’être. Nutrition is a lifestyle instrument to fulfill wellness and anti-aging visions that promise eternal youth, beauty and fitness. The model of Maslow’s hierarchy of needs explains that this is possible and that many people want more than just to .

The hierarchy of needs

According to the American psychologist Maslow, human needs . The basis of this pyramid are physiological needs such as eating, drinking and sleeping. At the second level are security needs such as health protection, stockpiling and security. Social needs build on this. These include, for example, friends, acceptance in the group and at work.  the needs of the ego such as autonomy and self-respect, and at the top is self-realization. According to Maslow, it can only take place once someone has met all other needs. However, disturbances on one of the “upper levels” influence all lower levels.

Applied to nutrition, this hierarchy of needs means we have enough to eat so we move at least to the second level of our needs or even higher. But when, for example, protecting health is no longer guaranteed, whether we are ill or need to protect our health, the physiological needs of the first level become the focus of this second level. Then we no longer need food to “only” , but we use food as a preventive measure against diseases or even to cure diseases.

Anyone who refuses any food in an acute gastrointestinal infection and eats oatmeal with a grated apple as a transitional measure, perceives the real needs of his body and thus supports recovery. This is a meaningful nutritional therapy.

However, various experts are awakening in us the need to eat against several diseases. It firmly establishes  rules: Low in fat, low in salt, rich in salad, vegetables, fruit and whole grain products, it should be the preventive diet for everyone.

Depending on the team of experts, it recommends the additional consumption of various dietary supplements. They often invoke scientific results. However, when viewed more, scientific proof is still lacking in many areas. Although there is at least one confirmatory study for each hypothesis, “evidence-based” criteria are applied according to which high demands are placed on the profile of meaningful studies (coming from evidence-based medicine), which leads to sobering results, for example in fat research.

Lean evidence against fat

One of the evidence-based criteria is the study design. This excludes the numerous epidemiological studies based on observations of different population groups. To create “convincing evidence” to support the “heart diet hypothesis” that low-fat diets protect against cardiovascular diseases, Lee Hooper’s research group at the University of Manchester tested randomized clinical intervention studies. In intervention studies, they give a group of trial participants a certain diet and a comparable group continues to eat as before. It regards them as the “gold standard of nutritionists” and are the most cost-intensive to implement.

The influence of a reduction in total fat intake, saturated fats or cholesterol or a shift in fat intake from saturated to unsaturated fats on the morbidity and mortality of cardiovascular disease was investigated. Other requirements for the study design were adequate randomisation, a control group and a minimum study duration of six months. Participants They only allowed participants be healthy adults. They excluded multifactorial interventions. To avoid manipulations by selecting the incoming studies as far as possible, two scientists decided they should include which studies in the meta-analysis according to the selection criteria. Only similarities were taken into account, in case of doubt they consulted a third expert.

The results were meagre: Of the almost 17,000 studies researched over the last 35 years, only 27 met the selection criteria. Only studies with a duration of over two years showed a minimal protective effect. Overall, the researchers summed up: “Despite decades of effort and thousands of selected test subjects, there is only limited and unconvincing evidence to date that the altered total fat intake or the change containing saturated, monounsaturated and polyunsaturated fats influences the morbidity and mortality of cardiovascular diseases.

Rules without foundation

Another disillusionment followed on the foot. It reflects the practical conversion of nourish-scientific realizations, which spring essentially from the nutrient science with us in the 10 rules to the healthy nutrition , in the nourishing circle and the nourishing pyramid. They should give orientation to everyone on the way to a healthier diet.

To check whether this menu, which is also valid in the USA, is being implemented, experts there developed the “Index for Healthy Eating”. It can collect up to 100 points by those who consume generous portions of bread, noodles, vegetables and fruit every day and are more reluctant to eat other foods, especially fat.

Is every point collected a health benefit? Evaluating the two largest prospective nutrition studies, the Nurses Health Study (women) and the Health Professional Study, with 170,000 subjects observed over an 8-year period, was rather devastating. No matter how the women were fed, the risk of becoming ill did not change, neither in cardiovascular diseases nor in tumour development nor in other civilisation diseases. There was a small difference among the men: with increasing points in the nutrition index, the risk of illness decreased. However, this effect was also so minimal that the authors demand that in future the preventive effect of dietary rules should first be tested before it flows into health policy.


The demand for evidence-based nutrition could thus call into question the work of those who, to the best of their knowledge, have tried in recent decades to motivate everyone, from infants to senior citizens, to change familiar eating habits in favour of new insights. They publish “the more good” studies, the more obvious it becomes how little we know about the invoked preventive effects of the right diet.

With fat, it took 11 years, in which four project leaders resigned their office, until the highest health authority concluded that the health-promoting effect of low-fat nutrition, they propagated which yesterday, was no longer valid today. This happened pretty much at the same time as the failed proof that the postulated so-called “healthy diet” prevented the most widespread diseases of civilization.

However, nutritional research faces a particular dilemma, as nutrition decisions often have to be made quickly. We eat three times a day - and most times cannot wait until the side effects and risks of what we eat have been clarified. Research often takes decades.

The scientist Prof. Dr. Hans Konrad Biesalski, who works in nutrition research at the University of Hohenheim, criticises the current science as too static, too conformist and too dogmatic. Knowledge that has been proven to date can mostly only be regarded as pre-scientific knowledge.

Multidisciplinary instead of causal

Prof. Dr. Biesalski’s proposed solution is based on the complex interactions of nutrition, health and disease. He calls for a nutrition science that is future-oriented and open to new findings, in genetic research. These point out that large individual differences, based on so-called polymorphisms, according to which the genetic disposition can differ from person to a person, for example, for forming different digestive enzymes, also determine very different eating habits. He also demands that nutrition science should lose its fear of contact with other sciences and thus become not only an interdisciplinary, but even a multidisciplinary science.

Nutrition science as an applied science has dedicated itself from its beginnings to interdisciplinary work and has a wide range of instruments at its disposal for the targeted uncovering of the interrelationships in which nutrition stands. According to their own model, it integrates humans as into social and ecological networks. All this affects developing diseases at least as much as what we eat - and it affects the eating habits of each individual.

Where food is experienced as a social event, meals determine the daily rhythm and shopping habits are not only oriented to the wallet or advertising, a meal with spaghetti and tomato sauce can have a different significance than where food happens in between, the same dish lands from the freezer to the microwave on the desk in the office and is eaten next to telephoning or where in modern experience gastronomy food is celebrated as an “event”, integrated into a complete entertainment programme.

Eating behaviour is influenced by both internal and external control. From the “inside” comes hunger, the emotions of a meal, the appreciation, which is also subject to many external influences and can change. Before the BSE crisis, beef in sausages was regarded as a sign of quality, with the crisis nobody wanted to eat beef in sausages or on plates any more, the disgust with it has long since disappeared - although the number of BSE cases that are becoming known is still increasing. Confidence-building measures from outside have almost regained the positive appreciation. Socioeconomic factors, such as the increasing number of single-person households, are among the various environmental factors that influence eating behaviour from the outside. Those who live alone feed themselves differently from those who are part of a family or community. According to Professor Dr. Ingrid-Ute Leonhäuser from the Justus Liebig University in Giessen, this interaction of all factors has so far been neglected. She states: “We know what and how many people should eat and eat. We know little about why people eat what they eat.”

One doesn’t eat like the other

Many years of experience in nutrition counselling comes a little closer to the phenomenon of why people eat, what they eat, in many individual cases, which, however, have no statistical significance for the time being.

A mother and her five-year-old daughter come to the nutrition consultation, driven by the concern that their lively child is too fat because the weight is above the norm. The family doctor advised her to do something as research would show that more and more children are suffering from overweight and that there is an urgent need for action. The girl loves to eat, loves to romp around and has a lot outdoors, and has every opportunity to do so. Mother and child are insecure. The kid’s “pump healthy.” He likes the food, no matter if apples, plum cake or bratwurst with potato salad. It prefers spaghetti - without sauce, but with butter. Daddy can cook them well - even if or because that’s all he can cook.

The doctor sends a sixteen-year-old adolescent with extreme obesity. He has started type I diabetes and must be given insulin. First, he tells us he is sitting in front of the computer until the early hours of the morning. He found his true friends on the Internet. He eats noodles, coke and chips on the side. His father is an alcoholic and moved out, his mother almost never at home. Nutritional advice? Doesn’t interest him. He’ll continue to eat his chips and coke, the noodles too. He just likes nothing else. But just talking about himself, having a counterpart to listen to - that’s important to him.

An overweight woman reports she has tried to lose weight countless times. For a few months it always went well, then the pounds climbed higher than ever before. Now she wants to start a new attempt and is looking for the ultimate diet. But please, not again with renouncing everything she likes to eat. She doesn’t feel like chastening herself anymore. She wants to eat what she likes. But how can she deal with her guilty conscience?

The doctors told the man he could eat anything again, just small meals. But he doesn’t succeed. Since they removed his stomach, he has been plagued by digestive disorders of the worst kind. Now he wants to know how small the meals must be. A whole roll or half a roll for breakfast? He will start again: with half a sandwich for the first breakfast, the second half for the second breakfast and a small portion of potatoes with butter for lunch and other small dishes that are coordinated with each other during the day. Soon he will be able to increase his quantities. The loop laid in the intestine will take over the storage functions of the stomach to a certain degree.

Many more factors need to be perceived in all examples to discover why everyone eats what they eat. It requires scientific “background knowledge” of how different foods affect the organism, for example, that chocolate lifts the mood. If they eat it out of (love’s) sorrow, it cannot be a matter of forbidding the chocolates to the person concerned, but foremost a way must be found of dealing with the sorrow. So we have to understand the world of experience of the individual to classify where the cause lies, why advice is sought, where the roots of the disturbances of his eating behaviour felt by the affected person lie. And again and again it is a matter of not distributing advice according to the watering can principle, but of working out a way of helping people to help themselves together. The general knowledge about nutrition is often large, among people seeking advice. However, it is complicated to explore this abundance and decide what is important for one’s own nutrition. And because of stupid advertising messages the orientation can be lost easily, which food is the superb and healthy for the individual.

Impulses instead of recipes

For thousands of years, humans have been able to feed themselves - even without scientific knowledge, based on experience and constant adaptation to the food supply offered by the environment. More decisive than the question of the health value of the food was the desire for what is “good from experience”, which shaped eating behaviour. Good potatoes can be on the table every lunchtime and are still eaten with pleasure while bad potatoes cause aversion at the first meal. Because raw potatoes lead to discomfort, because they are indigestible, anyone comes up to consume them in larger quantities.

If one bases one’s observation on the fact that everyone has sensors for what and how much would be good for them, the logical consequence is that one cannot delegate responsibility for one’s own nutritional behaviour to trained specialists. A well-founded nutrition consultation can and must therefore “only” aim at helping people to help themselves.

Anyone who knows he empties the entire contents of the fridge every evening after work and feels rather uncomfortable afterwards has the responsibility to change his behaviour, also with professional support. These changes include different points than “adapting” the actual contents of the refrigerator to the actual needs. Maybe a walk or a bath will help you relax and get rid of the stress of the day before they open the fridge - or maybe not. There are no patent recipes, only courageous experimentation and trial and error.

Both are difficult to grasp in scientific studies, but they are important for the individual’s world of experience, because - and this is also a truism - those who have learned to perceive their own needs and to integrate them into their social environment in such a way they themselves and the world around them are “well” with them, either remain or become less dependent on colourful, dazzling advertising for all those foods that are rather superfluous. Potatoes, pasta, bread, cheese, sausage, milk, vegetables and fruit - all staple foods that have a firm place in the tradition of our diet do not need large-scale advertising campaigns. A benchmark for the practice can therefore be: The more complex the advertising for a product, the more superfluous it is on the plate. To arouse a need for it, however, the (food) advertising uses our dreams and fantasies of a happy, healthy and fit world, in which only one margarine brand makes a good breakfast.

Hear what the genes say?

If “evidence-based nutrition” takes up all interrelationships, incorporates humanities and social science findings much more into its investigations, the rules for healthy nutrition will become much more complex. Then perhaps there will no longer be any nutritional rules recognised as valid because the individual differences in what each person needs cannot be grasped in simple rules or models. She may then discover that nutrition is much more than the sum of measurable individual components - and in principle finds back what centuries of experience have confirmed: There are good and bad eaters, fat and thin people, more disease-prone, more sensitive types and robust natures. Depending on which type and in which condition you are, the warm vegetable soup gets you better than the cold salad platter or vice versa.

However, it differs from the past in one respect: if previous experiences have influenced behaviour, this should in future lead to more scientific knowledge about the genetic make-up of the individual, i.e. those genetic engineering successes that Professor Dr. Biesalski says will lead to a targeted individual nutritional advice. As soon as diet-dependent diseases are detected by genetic investigations, the outbreak of the disease could at least be delayed, if not prevented, by targeted counselling and tailored diet plans. For example, it is becoming more and more clear that alcoholism is genetically determined. If “alcohol gene” is detected, they could take measures to protect the person concerned from addiction. The same is conceivable for diabetes, cardiovascular diseases or even tumour development.

But no light without shadow. What will be the training and job opportunities for the genetically predestined alcoholic? Do health insurances and life insurances charge higher premiums in the presence of diabetes, heart attack or tumor? If nutritional medical research is on its way to becoming a “transparent human being”, we must not leave ethical questions out in the cold.

Man is what he is?

Unlike animals, humans have had to prepare their meals since time immemorial to eat a balanced diet. Watering to remove unwanted ingredients, drying and fermenting (sauerkraut) to prolong shelf life and heating to increase digestibility are some of the oldest processes. Until the end of the Middle Ages they frowned it upon to eat raw fruit and vegetables or to drink water because in it sat the illnesses. Only with the advances in microbiology and improved hygienic conditions did raw food gain a firm place in the diet. Today, the following still applies to trips to tropical countries: Peel it, boil it, cook it or forget it. Montezuma’s revenge threatens some who ignore it.

In the meantime, hunger has long since ceased to be the main driving force behind developing new sources of food in the industrialized nations; instead, it is the administering of abundance that has to be carried out. Getting fed up in the land of milk and honey doesn’t seem easy. However, trend researchers have been describing for a long time what the future will bring: Food is no longer there to “only” satiate, but to meet the demands of aging populations for more health and thus more fitness, more attractiveness and more performance. The foods of the future will no longer be spaghetti, potatoes, vegetables or sausages, but functional foods. By definition, these are not remedies, but foods that increase physical and mental well-being and prevent diet-related diseases. Experience has shown that good food should be replaced by (pseudo?)scientifically good food. Monetary profit also plays a decisive role.

Spaghetti and potatoes, even cheese, sausage and meat or fruit and vegetables can hardly be used to make a profit according to market-economy rules if the supply is too high. However, this might be possible with genetically modified potatoes whose increased vitamin A content is intended to prevent eye diseases. The Hamburg-based company S.K. Enterprise also expects the launch of its functional food drink LipLac to generate a worldwide market volume of over 700 million euros annually. The drink “is supposed to influence the arteriosclerosis or cardiovascular risk by maintaining a healthy cholesterol level. LipLac has a bionic effect through natural nutritional substances that stimulate certain cholesterol-lowering processes in the body”. We are now looking for strong investors to support the launch of the product. A company based in southern Switzerland invented the praline, rich in vital substances, for a healthy enjoyment. It combines the ingredients of red wine, which are considered protecting the heart, with those of chocolate and other praline ingredients, which are considered promoting health. Chocolate bars are predestined for future functional foods, so to speak the “conscientious gourmet supplement”.

But the healthy food business has its price. Where science takes place to “design” food, food becomes an experiment. Where food designers use all their innovative power to develop new foods to remain marketable at all, our genetic makeup is expected to adapt at least as to the enrichment and modification of active ingredients in our daily food. The consequences of “novel food” are often only tested after market launch, as with the future drink LipLac.

So when food becomes a balancing act between science and experience, there is much to be said for doing it like the stupid farmer who does not eat what he does not know., Our enzyme equipment is based on the experience of past generations and not on the healthy products of today, which can be discarded again tomorrow because researchers have yet to discover their disease-causing potential. In principle, the nutritional rules that have been criticized at present remain valid: A diet with good basic foods such as bread, noodles, potatoes, vegetables, meat, fruit, milk, eggs, cheese and a delicious dessert for gourmets has already made many old healthy. However, everyone can only decide for himself who gets what best.

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