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AND OPTIMAL HEALTH
RECOMMENDATIONS TO PREVENT DISEASES
BASED ON SCIENCE, NOT MARKETING
MARÍA I. TAPIA
Vitaminas, minerales y salud óptima
© María I. Tapia 2018
All rights reserved
Cover: Finder Design
To my mother, wherever she is
To you, for reading this book, my first book
TABLE OF CONTENTS
VITAMINS AND MINERALS
1. A discovery that changed human health
2. Vitamins: those almost magical substances
3. The latest discoveries
4. What are vitamins useful for?
5. Minerals: our inalterable body component
6. What are minerals useful for?
SOURCES OF VITAMINS AND MINERALS
7. Surprising data: where we get vitamins and minerals
8. We are not what we eat, but rather what we make use of
9. A plant’s goal is not our survival, but rather its own
10. The micronutrient content of plants varies greatly
11. How vitamins are lost from foods
IS IT NORMAL TO HAVE DEFICIENCIES IN VITAMINS AND MINERALS?
12. How to know if we are consuming enough vitamins and minerals
13. A super-productive agriculture does not provide us with more micronutrients
14. Do we consume enough vitamins and minerals in developed countries?
15. What are the scarcest vitamins and minerals amongst the population of developed countries?
HOW TO GET THE VITAMINS AND MINERALS THAT WE NEED FROM OUR DIET
17. To get the nutrients we need, let’s it eat real food
18. Strategies to consume more vitamins and minerals without turning to supplements
19. How to increase consumption of the scarcest micronutrients in our diet
HOW TO LIVE A HEALTHIER LIFE
20. Let’s not blame our genes for our bad health
21. How we can improve our diets
22. What other aspects of our lifestyles we can improve
About the author
Your opinion matters
Another book by the author
If I had a T-shirt slogan for this whole book it would be: “I think you’ll find it’s a bit more complicated than that”.
—BEN GOLDACRE,Bad science
WHAT WILL YOU DISCOVER IN THIS BOOK?
I would bet that you would like someone to answer the following questions:
• What are the real values of vitamins and minerals?
• Do we have deficiencies in any of them?
• What are the long-term effects of moderate deficiencies in these substances?
• Can we be overweight or obese and at the same time be undernourished?
• Would we have better health if we provide our bodies with more vitamins and minerals?
• How can we get sufficient vitamins and minerals from our diets?
• How can we live a healthier life?
If I hit the mark and you want to know the answer to one of these questions, or to all, this book will help you.
WHY DID I WRITE THIS BOOK?
Because I believe that everyone has the right to have access to the best information available (explained in a simple and summarized way), despite never having read a scientific article nor ever having specific training in science. My goal is for you to access that information, which is emerging almost daily, and that you can apply it in your day to day.
WHY CAN YOU TRUST ME?
I must confess something: as I am writing these lines (with the book already written) I still doubt if I should include this sentence: I became a Doctor of Biochemistry and Molecular Biology at 26 years old. Over time I have learned that titles alone are not enough to show the professional value of a person. What really matters is experience.
For that reason I think it’s important for you to know that throughout the years I have worked in a pharmaceutical company and in various research centres (The Institut Pasteur, amongst others), on quite different subjects such as: metabolism regulation, development of new vaccines, functional foods, improvement of the quality of fruit, detection of chemical and microbiological contaminants in processed food, water quality... All those have a common base: biochemistry and molecular biology. The science of the small. The study of our most basic nature, that of chemicals1 and the molecules2 of life.
In 2016 I made a turn in my professional career path: I decided to be a spectator and narrator of science (without straying far from the path I already knew “from the inside”). Since then I have thrown myself into writing books based in science. You are about to read the first of them, this one that you have in your hands.
If there’s something I have practice in it is searching for and managing the best information; a quality that is quite needed today as we are bombarded constantly with scientific news about nutrition. Scientific? Nowadays, a lot of people talk about science. They critique investigations despite never having conducted an experiment. This does not invalidate those comments, of course; but analysing scientific information from a theoretical point of view is not the same as having the knowledge and background from working for almost twenty years in the field, since the credibility of the studies lies in the details. Modestly, I believe that I can help bring scientific advances to anyone with enough interest in improving their health.
There is something else that we cannot overlook. Most frequently, authors of books related to nutrition and health (supplements, diets, detox products, etc.) have a very defined prior opinion; and in their book or articles they promote these opinions with the scientific literature that is the most favourable to them, avoiding the studies that contradict them. (Like Ben Goldacre said, “There is so much information available on any topic related to nutrition in relation to health, that it will always be possible to find a wide selection of studies that will prove you right”. The quality of those studies is another question.)
If I wanted to know the answer to the questions posed at the beginning, and maybe wanted to make a decision about them, I would choose authors who try to approach the topic without already having taken a position. I think that impartiality is one of my best values.
THIS BOOK IS FOR YOU IF:
• You turn to science, and not to dogmas or advertising, for the answers to many questions related to nutrition and health.
• You accept that, sometimes, “It is not known” is the only reasonable response.
• When choosing between what is simple and what is true, you always prefer what is true.
Do not expect personalized diets or medical advice from this book. That is not my objective. I am not a nutritionist, nor a dietitian, nor a doctor. I am inviting you to see the world of vitamins and minerals through the lens of biology and biochemistry. You will discover what is currently known about vitamins and minerals as it related to health, and the cutting-edge research that is ongoing in this domain. You will also know the important questions that researchers are trying to answer.
To begin, let’s go through the history of the discovery of vitamins.
VITAMINS AND MINERALS
A DISCOVERY THAT CHANGED HUMAN HEALTH
Finding a needle in a haystack is much easier than isolating a vitamin. The one who seeks the needle knows what haystack to look in, but the one looking for the vitamin must first find the haystack.
—WALDEMAR KAEMPFFERT,What we know about vitamins (adapted), 1942
HOW DID WE GET HERE?
Eating has historically been a matter of survival. The main problem was getting the food. For many years, the meals of the majority of the population consisted mostly of cereals, legumes and a bit of meat at parties and other special moments. Sometimes some garden produce were added, whichever ones were in season.
Now we eat how only a few did back then: like the rich and the powerful. However, despite the abundance of food that crowds the colourful aisles of supermarkets, we feed ourselves with a limited variety of plant species, and a lot of themare becoming extinct.
It has only been a few years since we started relating food to health. And, since then, the concern about food has been ever-increasing. As well as the sometimes contradictory information. People are confused. And, in certain aspects, the researchers too.
Imagine that we are going to send astronauts into space with the food they need for several months in the form of pills. We can make pills with a mixture of carbohydrates, proteins and fats (the macronutrients), in the proportion that we want, and in enough quantity so that they have all the energy they need. But no more than that. What would happen? They would get sick and end up dying. Why, if they have plenty of energy? Because they need a few dozen more compounds to survive, and their bodies cannot make them. We are talking about vitamins, some minerals and other nutrients: the essential nutrients. What we nowfind so obvious we have only known for a short time. A flicker in the history of human beings.
Until the discovery of vitamins, about a hundred years ago, it was thought that foods contained only fats, carbohydrates and proteins (all three were known since 1827), in addition to minerals and water. And they were unaware of the nutritional importance of minerals. Technology had been sufficiently developed to break down foods into their major parts and analyse them separately. They separated fats, carbohydrates (or sugars, as they were called), proteins and minerals. When they analysed them and calculated what they all weighed together (with the scales they used at that time) they obtained one hundred percent of the original weight of the food, which is why for a long time nobody thought that there could be anything else in food. In fact, formulas of these three compounds were used to feed the babies, thinking that they could supply everything that was in the breast milk. How naïve. Or how arrogant, depending on how you look at it.
Practically since then we have been thinking about what proportion of each of the three macronutrients is necessary for optimal health. A question not yet resolved, given the intense debate that exists today on diets low in carbohydrates or low in fat, or on the ideal proportion of proteins that we should consume; or considering the endless number of food pyramids (or the modern version, the nutritional plate) that have been recommended for decades. And a question that perhaps is not so important if we take into consideration that the human metabolism is incredibly flexible, and that diets as different as that of an Eskimo (who consumes large amounts of fats) and those of some tribes that practically only eat plants, could be equally as healthy.
In addition, this debate on nutrients causes us to divert our attention from something more important: the quality of food.
But let’s get back to the vitamins. It is worth making a stop along the way and diving for a moment into the history of their discovery.
For a while everything was going relatively well, outside of the periods of famine. Wheat was the staple food in Europe and North America, and rice in Asia. But when they started deconstructing the foods and stripping them of some of their parts, for example the skin and the germ of the rice or the wheat, the problems started.
The seed of wheat (whole) has a lot of micronutrients, much more than that of rice or corn; it has vitamin A (that gives the flour a yellowish colour, before bleaching it), group B vitamins (niacin, folate) and vitamin E (alpha, beta and gamma tocopherols). Different molecules that perform different functions in our bodies. But these nutrients are not distributed homogeneously. Most of them are in the germ. When breaking the seed, these vitamins are exposed to the air, and the majority of them are destroyed, especially if bleaching or heating treatments are added to the system. What remains in the refined flour is not the living part of the plant (the germ, the embryo), but the food reserve of the seed, the endosperm, formed essentially by dead cells packed full of carbohydrates (starch).
Brown rice is not particularly poor in vitamins either; however, the husked grain consists in little more than the endosperm, rich in carbohydrates and almost devoid of vitamins and other essential micronutrients.
And why is the shell removed? Because the polyunsaturated fats in the outer layer of the cereal grain become rancid when rice (or wheat flour) is stored at high temperatures. The better the milling, the less vitamins will remain in the rice (or in the wheat). Around 1870, European colonists introduced steel roller mills in Asia; these machines were much more effective at removing the shell and producing the desired white rice. If the diet is varied, as it is today (in our environment), nothing happens; but if the base of the food is white rice or bread, like it was in many countries (and still is in some), the necessary vitamins and minerals are not obtained. It is important to keep in mind, also, that the vitamins and other micronutrients that are naturally contained in the seeds and cereal grains help assimilate carbohydrates (starch). In removing the shell, we must use our own reserves of vitamins to extract the energy contained in these carbohydrates.
The disaster came: many people started to get sick from pellagra or beriberi, diseases that you may not have even heard of, but which were very common until not so long ago. And they were terrible diseases.
Pellagra, for example, was the most frequent (and feared) disease among people in asylums and psychiatric hospitals at the end of the 18th century. It seems that there is no record of the disease before this time. The disease, considered a peculiar form of leprosy, prevailed in northern Italy and in other regions where corn, which had just been introduced from America, had become the main cereal, replacing rye. The disease was associated with poverty and the consumption of diets based on damaged corn. In 1784, the prevalence of pellagra in that area was so great that a hospital was founded in Lake Lugano to treat it. The success of the treatment of pellagra was attributed to factors other than diet, for example to rest, fresh air, water and sun.
In the United States, the disease was common at the beginning of the 19th century, during and after the American Civil War (1861–1865), coinciding with the shortage of food in the southern states. It was called the disease of the four “D’”: diarrhoea, dementia, dermatitis and death. The death rate was 69%. Since it appeared, pellagra was associated with poverty and the dependence on corn as the main staple food. It was proposed that it was caused by a toxin in mouldy corn.3
But towards the turn of the century (at the beginning of the twentieth century) other hypotheses also became popular: an infectious agent (“the germ of pellagra”), or perhaps some insect. However, something strange happened: the people who cared for those sick with pellagra did not contract the disease. In spite of this, and that at that time the existence of vitamins—“those miraculous chemical compounds from food capable of restoring the health of the body and mind”—was already known, politicians and scientists of the time remained convinced that pellagra was caused by a germ.
The deaths continued until 1937, when vitamin B3 (niacin) was (finally) isolated, and it was seen as the long-awaited cure. In 1941, the importance of the vitamin was so widely recognised that the US government ordered that it be added, by law, to bread.
Let’s travel now to Asia. Beriberi (“I can’t, I can’t”) is a disease that is so uncommon in our environment that it is practically unknown; nonetheless, it is a historic disease that caused havoc until the beginning of the twentieth century, especially among the poor who survived on diets where white or husked rice was the main food. In the 1860s, 30–40% of sailors in the Japanese navy were affected by the disease. The cause of beriberi was a mystery for many years: “bad” water? Some toxin? A “poisonous air that rises from the moist soil”? Finally, beriberi was linked to diet.
And, as so often happens in scientific research, chance helped a lot. The chickens that they were using in the experiments were fed for a period of time with white rice instead of brown rice, which is what they usually gave them (because it was considered inferior in quality), keeping the white rice for people; keen researchers observed that when the chickens ate white rice they got sick, and they recovered after going back to eating brown rice. Bingo! The disease was caused by the deficiency of “something” present in the brown rice, but not in the white. What I summarize in last sentence is something that intrigued researchers at the time for many years.
The (not so far off) idea of nutritional deficiencies rose for the first time from the study of beriberi. At that time no one had heard of this, nor had they heard of vitamins. But it was obvious that the diet had something to do with diseases: by replacing rice with meat, condensed milk and bread, sailors recovered; back then, it was thought to be because of the protein. We now know that it was not the protein, but rather a vitamin, thiamine (vitamin B1), that was responsible for the cure. In 1910, Funk (the Polish scientist who coined the word vitamin) started to split (separate into its parts) the rice husks. The problem is that the quantity of what he was looking for was very little (now we know that a ton of brown rice contains only a teaspoon of pure thiamine). But, finally, he was able to isolate a tiny sample of a crystalline substance, which turned out to be a mixture of vitamins (especially niacin). Thiamine was not isolated until 1926. More than 317 kilograms of rice husks were needed to get 100 milligrams (a thousandth of a gram) of thiamine crystals.
The history of the discovery of vitamins shows us many things. Among them, the surprisingly long period of time between making a scientific discovery and implementing it to protect the population. No better example than scurvy can be found.
Unlike pellagra and beriberi, scurvy is a very old disease; signs of the disease were found in skeleton remains of primitive humans. It was common in the north of Europe during the Middle Ages, when harvests were too poor to provide sufficient vitamin C during the long winters. At that time, it was treated by eating water cresses and fir leaves. It only started being noticed (and how!) when the technology that allowed ships to travel long distances was developed. Sailors started embarking on transoceanic voyages, struggling to survive for months without fruits or vegetables; the numbers became horrifying: scurvy killed or badly infected almost the entire crew.
As early as 1601 it was known that the consumption of berries, vegetables, certain herbs and citrus fruits were effective in preventing scurvy. That year, the English corsair Sir James Lancaster made the sailors of one of his ships take three spoonsful of lemon every morning, and the treatment was a success. However, the prestigious London College of Physicians saw scurvy as a “putrefactive” disease, that caused the affected tissues to become alkalized, and claimed that other acids could be as effective as lemon juice in treating the disease. As such, in the mid-1600s, doctors of the British ships embarked with diluted sulfuric acid!
In 1628, the positive effects of citrus fruits on the prevention of scurvy had already been published. But the discovery went unnoticed.
In 1747, the doctor and naval officer James Lind, doctor of the Royal Navy, carried out what could be considered the first clinical trial in history. And it was at open sea. He divided the sailors into pairs; they all ate the same and slept in the same cabins; the only difference was their treatment. He gave each one of the pairs for fourteen days (although fruits finished in seven) one of these ingredients: cider, a mixture of sulfuric acid and alcohol (!), vinegar, a paste from a mixture of a variety of spices, sea water and fruit (two oranges and a lemon). Those six were supposed remedies for scurvy. The men treated with lemons and oranges recovered so well and so quickly—in just seven days—that they helped Lind take care of the others. No other treatment was effective.
Lind published his results in 1753, in Treatise of the scurvy. However, until the year 1769, the Royal Army did not accept the idea that the disease could be prevented, and only from 1795 (almost 170 years after the first publication!) did they start carrying lemon juice in their ships to prevent scurvy among their crew. It did not matter how many times the connection between scurvy and fruits was shown; people would forget; the cures for scurvy (as for many of the diseases stemming from vitamin deficiency) would get lost, found and then lost again.
Scurvy appeared in Arctic explorers in 1820, in American gold prospectors in 1850, and in the Crimean War of 1853–1856 (they were sent cabbage specifically to treat the scurvy, but due to “bureaucratic errors” no one gave orders for it to be distributed among the crew; entire loads of cabbage were thrown overboard while the sailors were dying from the disease). It even appeared among the babies of well-educated and prosperous European and North American families in the early twentieth century and, a few years later, in the camps of war prisoners.
It took more than a century after Lind’s experiment in the ship for someone to really understand why fresh fruit and cabbage were effective in preventing scurvy. The key was vitamin C. Although the cargo holds of the ships carried sufficient calories so that the sailors would not die of starvation (they had dried and salty foods, so that they would not rot), it was too long for any man to hold out without vitamin C.
Although they had the solution right in front of them, and some even used it, it took centuries for the official bodies of the time to implement measures to tackle the disease and protect the population.
By the end of the 19th century, more than a third of the children in London were suffering from rickets; it was easy to recognise them: the sick children’s legs were so feeble that they bent. By the beginning of the 20th century, it was estimated that 80% of the child population was suffering from the disease, making rickets popular as “the English disease”. Its appearance on a large scale was more recent and more geographically restricted than that of scurvy or beriberi. The mummified remains of the Egyptians had no signs of the disease.
One researcher, Palm, realized in 1888 that the disease did not appear in southern Europe and, however, was frequent in northern latitudes, with little sunlight. He suggested that exposure to sunlight prevented rickets; but many argued that the cause of the disease was something else, for example inheritance or syphilis. During the turn of the century, a large part of the western medical community was unaware of (or disregarded) a remedy that had been popular among the peoples of the Baltic Sea and North Sea coasts: cod liver oil. It was not until the 1920s that all the confusion about the cause of rickets became clear: a vitamin D deficiency was responsible.
Many others lost their sight due to xerophthalmia. When it gets dark, the vision disappears, and everything turns black. It is night blindness, the first stage of the disease. Night blindness was also frequent among the sailors with scurvy. It appeared in long transoceanic journeys and, although it took longer to develop, it was just as scary. This disease was one of the first medical diseases to appear in historical records. Writings of Greek, Roman and Arabic doctors have been found in which they described the liver of animals as effective for the prevention and cure of the disease. Although today we would see it as an unconventional treatment, a papyrus scroll from 1550 BC described the treatment as crushing the liver of a lamb directly over the eyes of the infected patient.
In the 1880s it was confirmed that cod liver oil was effective in curing both night blindness and incipient corneal lesions; by the end of the century, cod liver oil was used routinely in Europe to treat both illnesses. However, until the 1900s it was not understood why.
Today there is a much more pleasant treatment: squeezing a single gelatine capsule in a child’s mouth can cure night blindness in just a few days.4 Its protection lasts at least half a year. And it costs about two cents per capsule. It is not even considered a medication. And what substance produces this miraculous cure? Vitamin A. The liver of well-nourished animals is a good source of vitamin A. That is why it was so effective.
This vitamin also plays a role in the functioning of the immune system. The lower the level of vitamin A in the body, the greater the risk of developing very severe infections, and of dying. This surprising relationship was known because children who received supplements of that vitamin had a 34% less risk of dying compared to those who did not receive them. Today it is known that the majority of well-fed people have sufficient vitamin A in their liver to last them at least a year. In addition, our bodies are capable of recycling the majority of the vitamin A; however, they do not have much vitamin C reserves. This is why the sailors noticed the symptoms of scurvy much earlier than those of night blindness.