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Elephants to Einstein
GA 352

III. Nutrition

23 January 1924, Dornach

I'd like to add something to what I said last Saturday. I can answer the two questions I have been given for today the next time. We have been speaking of poisons and their actions on human beings, and have learned from those poisons that for genuine knowledge we must rise to the supersensible aspect, to the spiritual aspects of the human being.

Today I'd like to complete the picture and add something to the discussion of elements that have such powerful poisonous effects. This concerns the work done by a more or less healthy body in nutrition. I have spoken on nutrition on a number of occasions, 6For instance, Steiner, R., in Cosmic Workings in Earth and Man (in GA 350), lecture of 22 Sept 1923. Tr. V.E. Evans. London: Rudolf Steiner Publishing Co. 1952. but let us speak again of some aspects relating to nutrition, taking into account what was said the last time.

To feed himself, man mainly takes in three or four kinds of foods. The first is protein, which you can get to know most easily by looking at a hen's egg. Protein is produced in plants as well as in animal and human bodies. Both human and animal bodies need not only the powers they have in them to produce protein, for every living body actually produces protein; they also need the protein which a plant produces quite independently. And the human body also takes in animal protein. Some scientists have suffered severe embarrassment very recently concerning this very protein. Twenty years ago it was still taught everywhere that people had to consume at least 120 grams of protein a day to stay healthy. The whole of nutrition was therefore geared to it that dishes were recommended which people should eat in order to have the right amount of protein; 120 grams were thought to be necessary.

Today scientists have completely abandoned that idea. They know that people do not serve their health by eating so much protein but actually serve their ill-health, with the greater part of the protein going putrid in the human intestinal organism. Consuming 120 grams of protein a day, therefore, the human organism constantly has something like rotting eggs in its gut, that pollutes the intestinal contents most dreadfully, sweating out poisons which then enter into the organism, into the body. This not only produces something in the body that later on in life causes hardening of the arteries, as it is called — most of this comes from eating too much protein —but also making people highly susceptible to infection with all kinds of infectious diseases. People are less at risk of catching infectious diseases— they must, of course, have the necessary amount — the less excess protein they consume. Anyone taking at lot of protein will more easily catch infectious diseases — diphtheria, smallpox — than someone who does not take in so much protein.

It is strange indeed that scientists are now saying people do not need 120 grams of protein but only 20 to 50 grams. This, they say, is the amount people really need every day. So quickly have scientists changed their views in two decades. So you see how much store you may set by anything said to have been scientifically established. For if it should happen that you need to find out about the subject and you take a 20-year-old encyclopaedia, you will read in the relevant chapter that you should have 120 grams of protein. If you consulted a later edition you would read: 20 to 50 grams, and that it will make you ill to take more. So you see how it is, basically, with scientific truths. You are informed what you should consider to be true or false, depending on the edition of the encyclopaedia you consult.

All this shows that this simply is not the way to get a clear picture about things that involve the spiritual dimension. And it gives us reason, if we really think about it, to enter into the spiritual aspects if we want to understand what happens when people consume protein. But this is the food that absolutely must still be processed in the intestines, in the lower body, and the lower body itself must have the power to digest this protein. You know that protein, especially fresh egg white, is semi-fluid. All protein is semi-fluid. Anything semi-fluid is accessible to the human ether body. The human ether body cannot do anything with solid matter, only with fluid matter. Human beings must therefore take all the food they consume in fluid form.

You will say that when people take salt, sugar, or the like, they are solid. Yes, but they are immediately dissolved. That is why we have saliva. The solid matter of which the actual physical body is made must never come into the human body from the outside world. From this you may learn: you have solid matter in you. You know that. Your bones are solid. But it is like this: the solid bones are created out of the fluid element in the human body; no solid from the outside world can ever enter into the human body. The human body must let all its solid parts arise out of the fluid sphere. You are thus able to say: we have solid matter in us and this is our physical body, but the physical body is wholly and entirely created out of the fluid sphere, and for the fluid sphere we have the ether body, a subtle body that cannot be seen but is present everywhere in the human being.

Protein must also be completely converted by the ether body, and this happens in the lower body. The higher aspects of the human being are also active there, as I have told you, but the protein must be processed in the ether body. The fluid sphere thus exists for the human ether body. And by merely knowing that protein has to be converted in the lower human body, you are able to realize that protein cannot have the hardest task in the human being, for it does not have to act up into the chest, it does not have to work up into the human head. You can see from this that protein cannot be a food of prime importance. We may say that people cannot possibly eat too little protein, for it is processed immediately in the lower body; it does not have to do much work. Protein is processed in the lower body. Even if people have a diet that is very low in protein, all the protein is processed immediately.

We can see, therefore, that human beings are perfectly able to manage with little protein. Scientists will now admit this, but years ago children in particular were fed excessive amounts of protein. And you know we see those children who in the 1870s and 1880s were given too much protein going about with hardening of the arteries, or they have already died of hardening of the arteries. The harmfulness of something does not show immediately, it only shows itself much later.

The second kind of foods are the fats. The fats we eat will of course also reach the lower body. But fats pass through the intestines and act most strongly on the middle human body, on the chest. For the middle body, the chest region, for proper nutrition of the heart, chest, and so on, it is therefore absolutely necessary to take in fatty substances.

We see from this that human beings above all need fatty substances in the chest region because that is the region where we breathe. What does this mean? It means that carbon, which we have in us, combines with oxygen. When carbon combines with oxygen we need to supply heat. What the fats do, when they themselves combine with oxygen, is to produce heat. Fats therefore contribute a great deal specifically to what is needed in the chest region.

Now we may say that proteins have a tendency to putrefy if they are not processed in the body, in the lower body. To have proteins in us that cannot be properly digested actually means that we have something like rotten eggs in our gut. I think you know the stink of rotten eggs, gentlemen, and the situation is that when people take too much protein they sweat out this stink of rotten eggs into their internal organism. They fill themselves with this stink of rotten eggs. If you leave eggs for some time they become rotten eggs, and they stink like rotten eggs. And the part that has not been digested in the body will of course also produce a stink in the body; the other part, which is digested, will not produce a stink but enter cleanly into the body. And that is the work of the ether body. The ether body exists to overcome and remove the rotten stink that develops. The way it is in the human body is that the ether body fights and overcomes the rotting process. The rotting process is overcome by the ether body in the human being. When a human being no longer has an ether body after death, he begins to rot away. So there you have it right in front of your nose, we might say, that a human being does not rot away while he is alive; as soon as he no longer lives, he rots. Why is that so? Because the ether body has gone when a person is dead. The ether body is therefore the part of the human being that prevents rotting. We therefore have a continuous battle going on inside us against rotting away, and it is the ether body which fights that battle in us.

I think, gentlemen, you only need to think this through and you'll see very clearly, just from the evidence of your eyes, that there must be an ether body, that in fact there has to be an ether body everywhere. For proteins are produced everywhere on earth, and they rot. The earth would have to stink to high heaven if the ether did not keep driving this rotting principle away. Both inside and outside the human organism, the ether fights against proteins going rotten all the time. This is something we must certainly consider.

When we come to the fats, we have to say that fats do not rot but go rancid—you all know this, if you have ever left fats somewhere outside; even butter will go rancid. Fats thus have the property of going rancid. Now if you have left butter to stand, you will not be able to say if it is rancid or good fresh butter unless you have developed an eye for it. But when you taste it on your tongue you will know right away that it is rancid. This has something to do with awareness, therefore, with sensation. Rotting has to do with our sense of smell, with something you can smell outside. It is different, of course, if you have rotten eggs or the scent of roses, but in either case you smell it. Not so the going rancid. Going rancid is something where we only put a name to it because of something more inward, our sense of taste.

This immediately shows that it has a lot more to do with an inner response than in the case of eggs going rotten. The middle human body, the chest body, has to do with everything that is an inner response coming to awareness; and spiritually it is the astral body. As you know, in the chest we have something that functions on an airy principle. We breathe in air. We transform air. The air has its rightful place in the chest. In the remaining part of the human body gases and types of air should only be produced sparingly. If too much gas is produced in the gut, pathological flatulence develops, and that is not healthy. The middle human body exists for the generation of gases. And the higher supersensible spiritual aspect which intervenes here —it intervenes in things that are gaseous by nature —is the human astral body. This fights the going rancid of fats in itself. Just as the ether body combats the rotting of proteins, so does the astral body combat the going rancid of fats. People would continually have rancid eructations from their own fats, they would taste rancid to themselves inwardly, if their astral bodies did not constantly fight this process of going rancid. We thus have this astral body inside us to prevent fats going rancid.

You see, gentlemen, this is truly marvellous, for you can see from this that things go very differently in the ordinary physical world outside than they do inside us. Out there in the physical world fats inevitably go rancid. Human beings are blessed in that they do not go rancid, or only if they develop an internal disease. The matter is, therefore, that in health human beings have their astral body so that they cannot go rancid. They only go rancid if they eat too much fat, so that the astral body is unable to cope, or if something or other causes too much fat to be produced; cannibals know more about this than we do. Inwardly, however, human beings do perceive it if they go rancid. We may say that if someone grows very rancid, which means that his astral body is not sufficiently active, he continually has an unpleasant taste in his mouth. This unpleasant taste in turn affects the stomach. And in this roundabout way people get diseases of the stomach and intestines from the rancid fat in them.

If you notice that a person is inwardly going rancid, then arsenic is a good medicine for fats he has inside him which are not digested. Arsenic prevents one getting fat; it strengthens the astral body. The result is that a person is then able to combat the process of going rancid. These things are extraordinarily important. When a person shows himself to have an inner tendency of being unable to overcome his rotting protein with the help of the ether body, some copper compound or other usually proves highly effective as a medicine. Copper is thus effective when abdominal diseases, intestinal diseases are caused directly by protein. But when you find that something comes to awareness in the mouth, in the taste, it will not help to give copper; in that case it has to be arsenic, because you must first of all strengthen the astral body. It will not do to say simply that diseases of one kind or another are in a particular part of the human being. You have to know where they come from, if they come from rotting protein in the gut or fats that have gone rancid and affect the intestines and the stomach via the taste in one's mouth.

You see, therefore, gentlemen, that inside us we have the opposite of what these substances show themselves to be on the outside. We have an astral body that combats the going rancid of fats, while the ordinary physical and material world simply makes fats go rancid.

A third food people eat are the substances known as carbohydrates. Carbohydrates are found particularly in potatoes, for instance, in lentils and beans, and of course in all cereal grains. The carbohydrates are in there. Very many of them also contain actual sugar, which we always take as a food, or the sugar is directly produced from those carbohydrates because we transform the substances we take in when we eat potatoes, for instance. Potatoes contain much starch. This sticky starch is converted to dextrin inside us and then into sugar. If you eat potatoes you are therefore really taking sugar, for the potato starch paste is converted to sugar in the human body. As you know, grapes are particularly rich in sugar, hence also the alcohol. Everything alcohol is to man is, apart from being alcohol, really due to its sugar content, for sugar is produced particularly from alcohol in the human organism.

The first kind of food thus was protein, the second kind fats and the third starch, sugar. We have seen that protein is digested in certain quantities, without going putrid, by the ether body. Fats are digested, without going rancid, by the astral body. Now to starch and sugar. Looking at the ether body we have to say it is mainly active in the lower body. The astral body is mainly active in the chest region. Now we come to something else. You all know —I won't say from personal experience, but from seeing people who are not like you — the effects of alcohol, and you know that alcohol causes a peculiar condition in people, first of all drunkenness, but we'll leave that aside for the moment. But as you know, the next day—we have spoken of this before 7Steiner, R, Health and Illness, vol. 2 (in GA 348), lecture of 8 January 1923. Tr. M. St Goar. New York: Anthroposophic Press 1981 and 1983. — one has a thick head, a hangover, as it is called. What does such a heavy head or hangover signify?

Well, gentlemen, you can see even the term 'thick head' refers to the human head. And if you have heard people— different from yourselves, of course — talk about the bit of a hangover they had the day before, you will hear them complain above all of their skulls. The skull aches, and if it did not ache it felt as if it would drop off their shoulders, and so on. What is really going on?

The function of the head is to combat what starch and sugar want. What do starch and sugar want? You only have to consider wine. As you know, the wine, the grapes, are harvested when autumn comes. They are pressed and the matter then ferments. When fermentation is complete, people drink the wine. By becoming wine through fermentation, wine has overcome the fermentation. But if you put wine into your stomach, something develops from it that becomes part of the food again. The alcohol is literally converted back. Now starch and sugar are substances that want to ferment. Starch and sugar mainly want to ferment in the human organism. If you drink alcohol, the alcohol drives away the powers in the head that prevent the fermentation of sugar and starch in the human being. Let us take a good look at this. Let us say you had potatoes on 22 January, you had some beans and you drank alcohol with them. Right then. If you had not taken alcohol your head would have remained sober. Potatoes and beans contain starch and the sugar that comes from starch. The head would have the power to prevent fermentation of the starch and sugar in the proper way. If you bring in alcohol, the head loses the ability to prevent the fermentation of the starch and sugar you have in you from the potatoes, and then the potatoes and beans, and other things, too, cereal grains, for example, begin to ferment inside you.

Instead of being prevented, fermentation occurs in the person. It occurs because of the inability of the head that has developed because of the alcohol, so that the person comes to be full of fermentative powers. In central Germany, in Thuringia, people have a strange popular expression. When someone talks nonsense people in Thuringia say: 'He ferments.' It is not something people say in this area, but those who have been to Germany will no doubt have heard it in central Germany. And when someone is talking nonsense all the time, people in central Germany, in Thuringia, call him 'an old wretch in ferment'. The situation is that in central Germany, people connect fermentation with confusion in the head, with fooling around. That is an excellent popular instinct. They know that when someone talks a lot of nonsense he is in ferment in his head. And if someone has been drinking and got a thick head, he does not talk nonsense, for he tends to be quiet, but the nonsense is inside him, it rumbles in him. The process which develops to prevent the fermentation of starch and sugar is therefore the opposite of the tangible effect of alcohol. We may say, therefore, that there is something in the human head that continually works in the direction of preventing the fermentation of everything the person has in him by way of starch and sugar.

No one will deny that the I, the actual human I, has its main seat in the head, just as the ether body has its seat in the lower part and the astral body in the middle part of the human body. The situation is that this actual I has to do with warmth qualities, just as the physical body has to do with solids, the ether body with fluids and the astral body with gases. The situation is that with everything that relates to his actual I, the human being makes warmth move. This can be seen in detail if we study the human body. The actual I is also connected with the blood, and the blood therefore produces warmth. But the actual I, of which human beings have conscious awareness, is also connected with glandular secretion, for instance. Because of this, glandular secretion is connected with temperature conditions. With its supersensible powers the actual I also uses the powers of the head to prevent fermentation. We are thus able to say: the ether body combats the rotting of proteins, the astral body combats fats going rancid, and the I combats the fermentation of sugar and starch.

This is also the reason why I had to tell you on one occasion 8See note 6. that eating too many potatoes is bad for the head. Excessive potato consumption affects the human being as follows. You see, a potato contains little protein, which basically makes it a good human food. And if people eat moderate amounts of potatoes together with other things, the potato is a good food, having little protein. But it contains an extraordinary amount of starch which has to be converted to sugar in the human being, first into dextrin and then into sugar. I told you on that earlier occasion that the head has to do a terrible lot of work when people eat too many potatoes, obviously, for the head has to prevent fermentation. People who eat too many potatoes and have to make a terrible effort in their heads to cope with potato fermentation therefore tend to be weak in the head. It is mainly the middle parts of the brain that grow weak, leaving only the front parts which make little effort to prevent potato fermentation. It is actually due to the fact that potatoes have come to be widely eaten in recent times that materialism has developed, for this is produced in the front part of the brain.

It is really peculiar. People think materialism is a matter of logic. To some extent materialism is nothing but the consequence of eating potatoes! Now I think you'll agree people do not really like it if they have to live mainly on potatoes, but they do like materialism. So they are really caught up in a contradiction. To be a proper materialist, one should really advise everyone to eat potatoes, for that would surely be the best way of being convinced of materialism. But it is something that does not happen with most people. However, if the materialistic monists, the Monist Association, wanted to be really effective in their fight, they should really make sure that other foods are as far as possible replaced with potatoes. Then the Monist Association would be terribly successful. It would not be quick, but over some decades the Monist Association would be most effective if it were to influence the eating of potatoes. Though the people they would seek to influence with their potato diet would also give them something to think about; and so they would not be all that successful.

One thing you can see from this is that the science of the spirit we work with here recognizes the true nature of materialism. Materialism does not know anything about the world of matter; the science of the spirit recognizes the potato in particular as the real creator of materialism. It is dreadfully malicious, the potato, crafty, sly to an excessive degree. For you see, people can only eat the tubers of potatoes, not even the eyes on a potato — they are harmful — and they certainly cannot eat the flowers, for the potato is a member of the deadly nightshade family and the flowers are poisonous. But what is poison? As I told you the last time, large amounts of a poison kill, small amounts, in fine distribution, are medicinal. Potato as such contains much sticky starch, it consists almost entirely of sticky starch. It would be quite unable to live, because the sticky starch would be terribly harmful to it. But it attracts poison from the world at the same time, and destroys the harmful effect that is inside itself. This is why I say it is crafty and sly. It has its poison which removes the effect that would be harmful to it. But the poison in potatoes is particularly harmful to humans; it does not give this ability to them but only the matter which it renders harmless in itself by using the poison. This really is something we may refer to by saying that the potato is a sly, crafty thing. And people must clearly understand that if they eat too many potatoes their midbrain will wither away and it is even possible that their senses also suffer from eating too many potatoes.

If someone eats too many potatoes as a child or a young person, his midbrain will become extraordinarily weak. But the midbrain is the source of the most important sense organs. In the midbrain lie four rounded eminences called colliculi, the thalamus, and so on, and excessive potato consumption even weakens one's eyesight, for this has its origins in the midbrain. Some eye conditions in old age are due to the person having been brought up eating too many potatoes as a child. A person then gets weak eyes, weak eyesight. It really is true that people in Europe suffered much less from weak eyesight in earlier times than they do now. And this is because apart from other things that influence the eyes (but less strongly, because they do not act from inside, electric light and so on) excessive potato consumption in particular is very harmful to the eyes, affecting our vision and even the ability to taste — even the ability to taste! You see, the consequence is as follows. Let us assume someone eats too many potatoes even as a child. Later in life you will very7 often find that such a person never knows when he has had enough, because his sense of taste has been ruined by potato consumption, while someone who has not eaten too many potatoes will know instinctively when he has had enough. This instinct, which is largely connected with the midbrain, is thus ruined by excessive potato consumption. This is something that has emerged particularly clearly in recent times.

From everything I have said you will see that people must take particular care to be strong enough to overcome firstly the rotting of proteins, secondly the getting rancid of fats, thirdly the fermentation of starch and sugar.

As I told you the last time, people cannot be complete anti-alcoholics — for if they do not take any alcohol at all, alcohol is produced inside them. This alcohol stays in the lower body; it does not go up to the head, for the head must be free from alcohol, otherwise it will be unable, as bearer of the I, to have proper control of the fermentation in the body. You see, you can now have an idea of the way in which human beings relate to their natural environment. Looking at rotting protein everywhere — animals rot away, plants rot away —you have to say: ether is also present everywhere, and this gradually balances it out again. Looking at fats, which are also found in plants, which are found everywhere, you have to say: these fats would gradually make it impossible for all living creatures to continue to live, both animals and humans, if the astral body were not present to combat the process of going rancid. The human being thus fights everything that exists in nature outside. And when the human being dies the ether body, astral body and I go away. They leave the physical body. The human being then moves on into the world of the spirit. What happens then? Well, gentlemen, you know what happens. The dead body immediately begins to rot, to go rancid and at the same time to ferment, though the rotting is more apparent to the eye and to the nose, for we only rarely go about with our noses blocked up. The rotting process is thus easily smelt. But to go and lie across a grave somewhere and taste if the fat of the dead body has gone rancid —that is something we do not normally do, and therefore people usually do not know about it. And the fermentation that takes place is not studied at all. So it truly is the case that because the I goes away the human body begins to ferment, because the astral body goes away the human body goes rancid, and because the ether body goes away the human body starts to rot. This is something human beings always have in them, but for as long as they live on earth they are always fighting it. Any48 one who denies that the ether body, the astral body and the I are present in the body as real spiritual entities simply has to be asked: What do you imagine? Why does the human being not rot away? Why does he not ferment? Why does he not go rancid? This would have to happen to the body if it were just a physical body.

What do our scientists do? They wait until a human being has died before they examine him. For they know precious little of the living human being compared to what they know of the anatomy of the dead body, when the human being has died. Everything you are able to learn from them really only relates to the dead body. Scientists always wait for the dead body. They are thus quite unable to know anything about the real human being, who is alive, for they do not consider him. And this is the great problem, that all the knowledge of our modern science —this really is only so since the seventeenth century—basically comes only from the dead body. But the dead body is no longer the human being, for we have to ask ourselves: what brings it about that the dead body which human beings have also when they are alive does not behave like the dead body, rotting, fermenting and going rancid? It is exactly when we take a real look at the living human being that we discover these supersensible aspects of human nature. And we then also find that the I is active mainly in the head, that the astral body is active mainly in the chest, and that the ether body is active mainly in the lower body. And scientists do not know anything about the lower body, for they believe the processes in there are the same as those in outside nature. But that is not so.

Well, gentlemen, it is interesting to study things by not shutting oneself away in one's study but going out among living people. You know there are spas where you get a smell of rotten eggs, in Marienbad 9Marienbad, spa, in what was formerly Bohemia. for instance, because the water contains hydrogen sulphide. Yes, really, people who like fine foods and are also fussy about smells have to go to such spas. And why do they go? Why do they sometimes spend several summer months in places where it smells as if there were rotten eggs everywhere? You see, it is like this. These people really have eaten too much protein and now come to the spa. They are covered with skin and the whole business is inside, and so they do not smell like that. But if we were able to smell it, they would smell horribly of rotten eggs inside. So all the people who inwardly smell of rotten eggs come to the spas where you get a smell of rotten eggs. And what happens? Well, you see, in one case the rotten egg smell is inside, and in the other it is outside. In the one case, where it is inside, the nose does not notice it; in the other case, where it is outside, the nose does notice. Head and belly are opposites. The rotten egg smell produced in the belly is combated when it comes from the head side, through the sense of smell. And the inner smell of rotten eggs is fought in spas that smell of rotten eggs.

This is very noticeable for anyone who is inclined to make such observations. It so happens that when I was a boy I had to go to such a spa. Every second day I had to go to a spring called Marienquelle. 10Marienquelle, Our Lady's Well. There you also get a smell of rotten eggs. While this is rather unpleasant outwardly, there being such a terrible smell, you suddenly begin to feel rather good in your belly. So if one is not sick, and does not have the rotten egg smell in one's belly, a feeling of greater vitality comes up. Anyone who is not driven away by the smell can experience this. Someone who holds his nose will of course not experience the contrast, will not have this springtime effect in the belly that comes if one really gives oneself up to the rotten egg smell. And rotten egg smell is an extraordinarily good medicine, for example, even if artificially produced. It will give the body the power to make atrophying muscles grow strong and firm again. People are not keen on such treatments, but in one respect they are extraordinarily useful. For you see, if the rotten egg smell comes to us from outside, spring comes inside, in the belly. And in spring everything grows and sprouts, and people can gain new strength when spring comes inside, in their bellies.

This then is what happens with people who ruin their digestion by eating too much during the winter. You see, when someone does not ruin his digestion by eating too much in winter, he shares in the spring that comes in the outside world. The lower body in particular participates in the spring very strongly. But if you want to really enjoy spring in the world of nature outside, you should as far as possible avoid such things as goose liver pate and so on. If you have eaten a lot of goose liver pate then the environment in your belly will always be the way it is below the surface of the soil in winter, not above ground but below ground. It is warm there, for it is where pits are dug to store potatoes through the winter. But it all goes rotten in the human being because the warmth is stored in the belly; spring does not come in the human being. And then he must find an artificial spring in the smell of rotten eggs. This is the contrast between I and ether body. I and ether body must be in balance in the human being. You can see from this that if one really studies things in the world of nature, going to a spa that has the smell of rotten eggs with open senses, the sensation of spring in one's belly teaches one that inwardly the opposite process takes effect as proteins begin to rot.

chart of human bodies

I wanted to add to what I said the last time. You know I told you that when someone has taken certain poisons he has to take liquid egg-white protein as an antidote. Things that are healthy become poisons if they are not treated properly in the body, if too much of them gets into the body. Protein can therefore drive away poison in the human being, but protein is itself poisonous if it rots in the body, if too much of it gets into the body. That is how close nutrition and poisoning are to one another. You have no doubt heard that excess food can become poison. A great many diseases are nutritional diseases, that is, people failed to consider that only certain amounts of some substances should be taken if the body is to cope with them.

I'll ask them to tell you when the next talk will be, because I won't be here on Saturday. I'll be in Bern then.