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Yin-Yang, Science and "Macrobiotic" Cancer
by Carlo Guglielmo


In this follow up to my article, first of all I wish to thank very much all the friends and teachers that contributed with their comments, and then to respond to the principal questions and remarks that I received. At the end, I will add some considerations.


1. B12 deficiency in vegans does not exist, it is a myth created by the meat and dairy industry.

Carlo: Unfortunately, B12 deficiency in vegans is a documented fact: please see references in my article. Vegetarian institutions emphasize the importance of vegetarians and especially vegans taking vitamin. B12 supplements.

As a very authoritative example of a dedicated vegan doctor recommending vitamin B12 supplementation, please refer to Dr. Neal Barnard and the Physicians Committee for Responsible Medicine site

Macrobiotic people, also if not vegan in principle, may eat such a little amount of animal food so as to be at risk of Vitamin. B12 deficiency.

At least two studies document this fact. The first one, “Vitamin B12 status in a macrobiotic community”, published in 1991, has been conducted within the macrobiotic communities of Boston, MA, and Middletown, CT.

The study showed that many of the macrobiotic individuals tested were lacking vitamin B12 to a certain extent, and probably, with the more sensitive tests available today, the results would have been even worse. At that time no test for Homocysteine was conducted, for example. Everybody can download for free and check by himself the study here:

The second study, while not specifically speaking of macrobiotic people, checked and compared the vitamin B12 (and anti oxidants) status of people that:

1. ate no animal food at all.
2. ate only fish / meat once a week (and this is roughly our case).
3. ate eggs and milk / dairy frequently.
4. ate an omnivore diet rich in meat.

The study gave similar results employing a wider range of tests, included the one for homocysteine concentration in blood. The less animal food that was eaten, the worse was the vitamin B12 status, and higher was the level of Homocysteine in blood, so the approach similar to the macrobiotic one fared worse than the lacto ovo vegetarian one, from this point of view.

The study is Total Homocysteine, Vitamin B12, and Total Antioxidant Status in Vegetarians,
freely downloadable here:

It is true that we must be aware of the meat and dairy industry interest in this topic. However, it is not impossible to discriminate when a specific study or research is nothing more than an advertisement for these industries, or a good and honest one. The studies cited in the references are all of very high quality and solidly based on facts. Of course, it is necessary to read them thoroughly in order to verify my affirmation.

2. It is demonstrated that vegans are far more healthy than omnivores, so there is no reason to worry about vitamin B12 deficiency.

Carlo: Eating a lot of vegetables and fruits, and reducing or avoiding animal foods, sugar and chemicals, definitely improves one's health conditions. Nevertheless, in this way it is still possible to slowly determine a lack of Vitamin B12 and other substances, and it can create problems at a later time, even decades later.

3. My affirmations and concerns about B12 are groundless, and that is demonstrated from a
study cited
here: (the study is “Staging B12 status in Vegetarians”, and it is freely downloadable here: )

Carlo: Actually this study confirms my affirmations and concerns. In the very first page it says that “dietary deficiency of vitamin B12 results from a strict vegan (all plant food) diet”, while “vegetarians who are not vegans (...) ingest adequate amounts of vitamin B12 in animal (e.g., egg, milk, and other) products”.

The author then says that Vitamin B12 is reabsorbed from the intestine and recycled, so that an healthy and adult vegan can avoid B12 deficiency for many years, even 20 – 30 years (page 1217 S). But this only means that, when all organ conditions are perfect, deficiency can be delayed.

In fact (page 1215 S): “If daily vitamin B- 12 absorption continues to be less than daily vitamin B-12 loss, negative balance will progress to Stage II, depletion of stores. At this point, many vegetarians stabilize for years with depleted stores, because depleted stores trigger upregulation of healthy machinery for absorption, making more efficient the absorption of the trace amount of vitamin B-12 from bacterial contamination of the small intestine and vitamin B- 12 secreted in the bile.

Eventually, however, continuing slight negative balance will deplete vitamin B-12 stores, after which Stage III negative balance occurs (biochemical deficiency, i.e., inadequate vitamin B-12 for normal vitamin B-12-dependent biochemical reactions, sometimes called preclinical deficiency)”.

Moreover, if the gastric or intestinal efficiency is not perfect, deficiency can occur far earlier, because B12 is not adequately absorbed, the same study states. This is a rather common situation both for omnivores and vegetarians but, according to the author, it is a more frequent occurrence in vegetarians, due to a less efficient utilization of iron from vegetable sources.

In fact (page 1215 S): “iron from plant foods averages 3% absorbable; iron from animal foods averages 15% absorbable. Therefore, iron deficiency is twice as common in vegetarians as in omnivores. Because some vegetarians, especially those consuming restrictive diets, are at greater risk for deficiencies than omnivores, all vegetarians should be tested for iron disorders. Prolonged iron deficiency damages the gastric mucosa and promotes atrophic gastritis and gastric atrophy, including loss of gastric acid and IF secretion, and therefore diminished vitamin B-12 absorption. This would cause vitamin B-12 deficiency in twice as many vegetarians as omnivores”.

The study also states that the situation is even worse if one individual becomes vegan without large Vitamin B12 stores in the liver, a not infrequent possibility, or for children of vegan mothers.

Actually this study is aimed to identify the best laboratory tests to detect vitamin B12 deficiency, not to demonstrate the possibility to thrive on a strict vegan diet, and its affirmations clearly sustain, complete and precise the ones from the other references I reported in my article.

4. Many vegan groups and populations have demonstrated, through-out human history, that vegan nutrition is safe.

Carlo: Actually there are no data to support this thesis. It is possible that vegan monks stay healthy for a long time because they start their diet when adults, but probably many of them actually suffered in the past and suffer now for vitamin deficiency. They did not necessarily live a long time, or were healthy.

Moreover, monks have a very different way of life from common people, and practice powerful techniques that probably can help in optimizing the resources from food. In Daoism, practices are known that can help you to live almost without food, but of course this is very far from what common people regard living a normal life.

No population in the world has been vegan for generations: animal food has always been enjoyed if only available. Of course, specific religious groups may be vegan, and this is more common in India.

The only study of which I am aware on vegetarians living in India finds a very widespread B12 deficiency, even if the authors report that this situation cannot be completely attributed to a vegetarian diet but also to other factors. In any case, deficiency is there, not an adequate level of this vitamin.

(Please refer to this free downloadable article: “Hyperhomocysteinemia and elevated methylmalonic acid indicate a high prevalence of cobalamin deficiency in Asian Indians”, available here: and the comment to the same study available here:).

It may be helpful to remember here the Ohsawa's book “Zen Macrobiotics”, in which ten eating patterns are proposed as “ways to health”, and where the most wide one includes only 10% of grains and 30 % of animal foods, plus vegetables and fruits, while the most strict one is totally vegan and based only on grains. Apart from the details and proportions, the general idea is a good, flexible and realistic one.

Vegan diets, as well as animal food based ones like the chetogenic diet, are both legitimate, because a human being is able to sustain himself only on vegetables or animal foods for a pretty long time, if necessary. Otherwise, we could not explain some good results obtained with the Atkins diet, for example in rebalancing blood risk factors for cardiovascular diseases or metabolic syndrome.

This comes from the fact that humans have been able to survive on many different foods during their evolution, thanks to the development of specific abilities to optimize the use of the available nutrients (as vitamin B12).

However, those diets are at the limits of the human ability for survival, and humans usually sustained themselves on diets in which both vegetables and animal foods were present in different proportions according to climate.

(For a very balanced view on this subject, please refer to “Hunter-gatherers diets: a different perspective”, freely downloadable here:). Extreme diets such as vegan or semi-vegan ones, as well as highly carnivorous ones, are clearly sustainable only for a imitate period of time, even if vegan ones may be continued far longer than the ones that include a lot of animal foods.

How much animal food is necessary in our present way of living, and for each individual, is something that we must still discover, and experiment with, but starting from the fact that it represents a legitimate part of the human way of eating.

5. If both scientific conclusions and the ones based on yin-yang are not absolutes, why should we trust only those coming from science?

Carlo: I completely agree that it would be foolish. Science is absolutely blind with regard to many realms of our existence. I am speaking about a dialogue. We have much to learn and much to teach, but if we only stay within the limits of our philosophy, we end in making mistakes. The data from science are very interesting for us because we can evaluate them according to our yin-yang principle, so expanding our understanding of reality.

And if the data suggest that a substantial number of macrobiotic friends may be lacking B12 and presenting high levels of a toxic substance as homocysteine in the blood, there is no profit in trying to nullify this truth.

In any case, the way to clear this quarrel is very simple: anyone interested can have his own blood tests done and check the results. It seems that the best test for screening an early negative Vitamin B12 balance is the test for serum Holotranscobalamin II, while the test for Homocysteine is important in order to show the presence of an unnoticed but already existing – even if not clinically evident yet – metabolical damage. Of course, this is a matter to be discussed with a qualified Physician.

6. Yin-yang and science are the same thing. If intuition is refined, it can be a tool as reliable as science in order to understand reality.

Carlo: The yin-yang method has been born in China around 300 B.C., as a way to organize the data from senses, and the daily experience of living, in a coherent way. The underlying paradigm, at that time, was that humanity has to adapt to an harmonious and cyclically changing nature. According to this view of the world, people can stay healthy, and can even reach superhuman states, if they are able to find their right place in the order of the universe, and flow with its law.

Actually, not only ordinary senses were used in order to reach that goal, but also superhuman senses and abilities developed through special practices. It is also important to note that this method was originally based on Chinese language, which is far less definite and far more open to paradox than western languages, and that it never developed a clear concept of cause and effect, relying more on the idea of influence and attunement with the natural order.

Modern science springs, around the fifteenth and sixteenth centuries, from a very strict interplay between ordinary senses, intellect working on the basis of non-contradiction principle, mathematics and technology. Cause and effect is the cornerstone of this way to consider the reality, at least until the development of quantum mechanics. The paradigm in which modern science is born is an individualistic one, aimed to free man from dependency on nature.

So yin-yang and modern science are both in contact with reality, but approach it from different perspectives and using different tools. As I understand it, the greatness of George Ohsawa stays in his efforts to start a dialogue between these two paradigms, and I believe that his vision is still an inspiring one for our present times. Hopefully, it could lead to integrate these two approaches in one higher order future approach. But we are still not able to do that well, and sometimes we are not rigorous enough even in applying yin-yang itself, so we must learn more from the other side.

An example of how lightly yin-yang is often applied can be offered by referring to a classical question in macrobiotic lessons: why water expands when heat is applied to it (which is no surprise) and also when it freezes? The usual “macrobiotic” answer is: because Oxygen is yin and Hydrogen is yang. When cold is applied, the more yang Hydrogen attracts it and becomes more yin. Necessarily, the attraction between Oxygen and this yinnized Hydrogen diminishes, so the molecule expands, making ice light and able to float on water.

It is an attractive answer, and correct under the yin-yang point of view, but it is not true.

What actually happens is that, when freezing, the water molecules (and not the atoms within the molecules) arrange themselves at the vertex and in the center of a tetrahedron (a pyramid-like shape), with Oxygen and Hydrogen atoms of different molecules united by hydrogen bonds, so that ice becomes structured in an expanded way compared to water. All this is still in perfect harmony with yin-yang principles, but it is completely different from what is stated in the classical answer above.

It must also be said that it is absurd to think that the water molecules themselves can expand under the weak influence of a few degrees difference in temperature, because the Oxygen and Hydrogen atoms in the water molecule are united by very strong covalent bonds that – differently from the weaker hydrogen bonds that link together water molecules in ice - do not allow for that. If something like this could happen it would subvert modern Physics.

Now, it seems that nobody ever had the desire to check if this affirmation actually corresponds to reality, and I believe that the same is true for many assertions taken for granted in this field.

So, again, I am sure that yin-yang can really help in solving many problems and suggesting new hypotheses, but we must learn to use it rigorously. I personally experienced some of this difficulty when I gave my contribution to the work of one of the leading epidemiologists in Italy, who is presently studying the risk factors for breast cancer.

He asked me to try to figure out for him, according to yin-yang and starting from the available scientific data on this subject, how foods influence the level of a very important class of hormones, the Insulin-like Growth factors, and related binding proteins.

I checked the data, interpreted them according to yin-yang and combined them with my macrobiotic experience, and finally proposed a few ideas that could be experimentally checked. So I believe that it is definitely possible to reach useful conclusions with yin-yang, even entering the scientific ground, but I know that it is not so easy to do.

(I've written a book that tries to carry the dialogue between yin-yang and science a little further on. The book is titled “Il grande libro dell'Ecodieta”, and it is published in Italian by Edizioni Mediterranean.

The first third of the book presents the scientific data that we have about the food that human beings did eat during the last couple of millions years of their evolution, plus the principal data about the favourable and unfavourable effects on the health of the main groups of modern foods. From this first section, a general indication of the best eating pattern for the human being comes out, and it is very in tune with the macrobiotic approach.

I decided to start with the scientific approach because this is the language of our modern society, and I wanted to reach not only macrobiotic people but the widest audience. The second part of the book is dedicated to yin-yang and its use, and shows how this method can confirm, pinpoint and make more practically and flexibly usable the data from science, beyond supplying new information by itself. The third part is about how to address specific sicknesses with food and treatments.)

7. Cancer in macrobiotic people comes from eating every day pressure cooked brown rice or other grains. This creates a too contracted condition, that makes people overeat and eat in a disorderly way.

Carlo: I agree that eating everyday pressure cooked brown rice makes people too yang in the long run, and that this contributes to overeating and attraction to sweets, so leading to several kinds of problems. A wider range of cooking methods and preparation should be routinely used. However, I believe that some stronger factors – as the ones proposed in my article - are at the core of such a big problem as cancer, even if overeating and sweets can possibly contribute.

8. I am deadly allergic to fish and fish oils, and dislike meat. How can I get adequate amounts of B12 and Omega-3 Fats?

Carlo: Any individual health problem has its own particularities, and must be discussed with a qualified therapist. However, in general it can be said that free range eggs and poultry contain a certain amount of both long chain omega-3 fatty acids and vitamin B12.

Milk contains B12. It is better to learn how to introduce these foods in a balanced way and in proper amounts, than risking a Vitamin B12 depletion. An alternative, or in addition, supplements are there.

However, supplements only supply some definite nutrients that we are aware of, while a lack of B12 may indicate a lack of many other nutrients contained in animal foods such as zinc, Vitamin B6, and more. A whole food is always very different from a supplement.

Short-chain omega – 3 fatty acids, from which the long-chain ones can be synthesized, are also contained in flaxseed oil and green vegetables, that should be regularly consumed. However, the synthesis of long-chain omega 3 fatty acids from the short-chain ones is often not sufficient to satisfy the body needs, hence the need for the animal foods in which they are already present.

9. Depletion of Jing is not necessarily linked with being skinny. The classical Chinese medicine views for depletion of Jing include: stress, over consumption of foods, alcohol and drugs, excessive sex, excess or lack of exercise, lack of sleep, poor breathing and natural aging.

Carlo: I don't put in connection the fact of being lean with jing depletion, and I am aware of the classical Chinese view on this subject , that seems very valuable to me. However, I am referring here to an impression of “emptying”, a kind of “exhaustion” that some macrobiotic individuals show, and that can be easily noticed by a trained eye, if only attention is paid to it.

Moreover, my suggestion is that vitamin B12, being so important for correct DNA reproduction and expression, has to do with jing depletion, even if this is something that the classical Chinese view could not understand in ancient times.


The problem of cancer is a huge one, and I do not pretend to have exhaustively or perfectly identified the factors that can contribute to its manifestation in macrobiotic people. However, the problems that I mentioned definitely exist, derive from our current way of interpreting the macrobiotic way of eating, ask for a solution, and probably can help us to understand also the cancer issue.

It could even be that the present global environmental unbalance, added to the lack of natural selection in the first years of life, are factors too strong to be overcomed only by a good way of eating and an active life.

And certainly the emotional problems have a role bigger than what we usually take into account, when dealing with this specific sickness. If things are like that, there's nothing to hide. We know that many people succeed in healing their cancers with macrobiotics, and very probably our way of eating still prevents many cases of this illness. What we have to offer is of the utmost importance for humanity, even if we are not able to completely prevent this sickness.

In any case, the main point here does not regard only vitamin B12 or D, Omega 3 and 6 fats, or any other specific nutrient, but our attitude toward the facts that disturb us, and oppose our idea of what the reality is. We just need to look at the problems as they are, without trying to explain them off in a simplistic way.

An example of this attitude is attributing the problem of cancer in macrobiotic people only to minimal mistakes within an otherwise perfect way of cooking and eating.

If we say that it is possible to get cancer only from, say, sautéing too much our vegetables, or eating too many cookies, or pouring too much raw oil on our salad, or something similar as we have indeed heard, we not only say something that it is very probably not true, but also create an attitude of fear and rigidity in many friends that trust our judgment and experience. This cannot be a road to liberty and happiness.

From experience to dogma

Every school of thought, or spiritual path, starts with an enlightening experience that shows aspects of reality that were hidden until that moment. As time passes the experience fades, and knowledge remains. After a longer time, even knowledge ages, loses its contact with reality, and dogma arises.

If we wish to avoid that eventuality, or at least to delay it as long as possible, it is essential that we strive to keep in touch with reality. And we know very well that the most painful experiences are the most useful ones, with regard to keeping us aware and alert.

Believing that we know how to stay healthy, how to prevent and cure any sickness, and that because of that we must become leaders of the new world and save the Humanity from the dangers in which it lives, would be a delusional attitude. I would like to suggest another approach.

Nourishing the Future

Many of us have children. From them we learnt that we cannot really lead another persons' life to a big extent. Our children have their way to go, their goals, limits and experiences to live just as we have. If we believe that we understand everything about life, and so we can guide them to reach their happiness, we create unhappiness. We can just help, and even that not so much. The same is true with Humanity.

We don't know what future Humanity will choose to live, nor which future is actually the best for it. We learned a few things from our macrobiotic practice, because we experienced them and because we apply a method that really helps in understanding things, but we are ignorant about many more matters.

The only attitude that we can reasonably cultivate is the one of nourishing the future, as we nourish our children, with good food, a little knowledge, a few dreams, and many unanswered questions, helping the future to grow according to its own way. We can put the little we know in the big flow of the human evolution, and let Humanity take or reject what it chooses to.

Let's say that we can strive to become good ingredients of
the cosmic soup, knowing well that we are not the Cook.

If we keep ourselves open and eager to learn from reality, also when it opposes or disappoints us, we will be able to stay flexible and helpful to others for a long time, putting something positive and valuable in the flow. And this can really make a difference, especially in a deeply transformational historical period as the one we presently live in.

Here in the center of the spiral of history, what we learned and can offer to others – even if very limited - can make a critical difference for everybody.

Posted- January 2006


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