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Margaret Moss on biochemical individuality |
Sometimes, when I read health advice, I cringe, thinking, if I did what they tell us, I’d be really ill. That is because my body chemistry is not the same as yours, and yours is not the same as your friend’s. There are differences in our genes, called polymorphisms, which make our chemistry work differently. There are also differences in which genes are expressed, or activated, depending on our environment. These differences are called epigenetic. Genes are passed on from generation to generation, often only causing a problem when two carriers mate together, producing a damaged offspring. Epigenetic changes can affect future generations too. Grand-daughters of women who suffered in the Dutch famine in the 1940s are affected by their grandmothers’ starvation. We are not clones... We are not clones. We know that there is room in the world for those with different aptitudes. Some make better parents, some are skilled musicians, some can design safe bridges, some are prepared to carry out repetitive tasks, and some bring consolation to the sick and dying. We need that variety. We also need different body chemistry, as some of us will be more likely to survive in different conditions of cold, disease or famine, to keep the human race going. In Ireland only a few varieties of potato were used. When blight came, the harvest was disastrous, and people starved. In South America, there were many varieties of potato, and many resisted the blight. We need many varieties of people, for the same reason. Fructose is a sugar that is in fruit, and is part of honey and table sugar. Genes that are a problem in some situations, like fructose intolerance in the Western world, may have been no problem in the past, when sugar was scarce. Food sensitivity is chemical sensitivity. Food sensitivity is chemical sensitivity. If you are sensitive to chemicals in foods, you are likely to have a problem with similar chemicals in the environment. For example if you do not make enough sulphate, you may have a problem with oranges and spinach, and with some disinfectants. Food allergy is different from food sensitivity. It is a disorder of the immune system, and it can also go with allergy to environmental substances. Those allergic to birch pollen are likely to be allergic to certain fruits and vegetables, like apple and carrot. When the birches are flowering, they may be worse affected by these foods than usual, because the total load of allergens is too much for them. IgE mediated allergy Some people die because they are allergic to certain foods. They have a lot of a specific antibody to these foods, called IgE. Such reactions can be rapid. In some people, only a tiny amount of an allergenic substance can kill. Most reactions to foods are slower, and larger quantities are needed to cause a reaction. They are often reactions to a chemical, or a class of chemicals in foods and in the environment. It is the quantity of such chemicals encountered that causes the reaction. Drugs are powerful, toxic chemicals, and can kill susceptible people. Poor detoxification Chemical sensitivity, and so food sensitivity, may be due to poor detoxification. Detoxification is the process of changing fat soluble chemicals into water soluble ones, so that they may be excreted in urine. This process may involve more than one chemical reaction. One major method of detoxification is oxidation, the addition of oxygen to a compound. There is a family of enzymes, called Cytochrome P450, or CYP, that do this. Different people have slightly different genes, which produce more or less efficient versions of some of the CYP enzymes. Also how much of these enzymes we make depends on our lifestyle and environment. Those who drink a lot of alcohol make lots of one of these enzymes called CYP2E1. If they go into hospital, and are unable to consume alcohol, they may cope with the drugs they are given, because the 2E1 is available to deal with them. A teetotaller may have more of a problem with the drugs. People who have grapefruit or grapefruit juice reduce the effectiveness of a different enzyme, called CYP3A4. After eating grapefruit, the enzyme is not able to detoxify certain drugs like statins properly, and so the effect of the drug is much greater than it should be. The drug side effects become much worse than usual. People are told not to consume grapefruit with such drugs. However, the drug Artemether, used for malaria, may work better if given with grapefruit. More enzymatic activity In some cases, the CYP enzymes make a substance into a more toxic chemical. What is then needed is for a second enzyme to take over, add something to make the harmful chemical water soluble, and then it can be removed in urine. If the second enzyme is not sufficiently active, the toxic chemical may remain, and may cause damage to the body. People with Gilbert’s Syndrome are inefficient at adding glucuronide to chemicals, which may not matter, if they are efficient at adding sulphate instead. However, inefficiency at adding both of these is a problem. The body is designed with redundancy, the ability to deal with issues in more than one way, so that if one process fails, another can substitute for it. This is rather like the situation in a good hospital, that has extra wards and staff that seem to be redundant, but are available for emergencies. A poor hospital is working at capacity all the time, and cannot cope with an epidemic or bus crash. Alcohol is oxidised to aldehyde, a process that requires zinc and vitamin B3. It is aldehyde which causes a hangover. The aldehyde needs to be oxidised to an acid, which can be excreted in urine. This requires zinc and vitamin B3, or molybdenum and vitamin B2. Many Japanese, and some others are inefficient at this, and flush after drinking alcohol. Sulphites are used as preservatives. An enzyme oxidises sulphite to make sulphate, which is beneficial. Those with poor enzyme activity may have an asthma attack, after eating foods containing sulphite preservatives, or after breathing in coal smoke. Poor activity of this enzyme also occurs in a significant proportion of autistic people. If I eat fish I smell of fish. That is because I cannot process the trimethylanine in fish. There are thought to be a few thousand of us in the UK. Some smell fishy also after eating eggs. When I ate fruit or sugar, my blood sugar could drop drastically, giving me a terrible hunger. This is because I cannot process a sugar in them, which is called fructose. I am fructose intolerant. This is fairly rare, but fructose malabsorption is common. This is the condition where a person consumes too much sugar, honey, fruit juice or fruit. All the fructose cannot be absorbed from the gut into the bloodstream. What remains in the gut is fermented by bacteria, making gas, and causing pain and diarrhoea. Often irritable bowel syndrome is just a matter of too much fructose. If you read about these problems, you may be confused, as some writers call fructose malabsorption fructose intolerance. We need vitamins, but the right ones in the right amount We all need some vitamin A, but not too much. When I ate foods rich in beta carotene, like carrots or kale, I rapidly converted it to vitamin A, which poisoned my liver cell membranes. In freezing times, when there was little fruit or vegetable available, this ultra-efficient conversion from carotene to vitamin A might have kept my ancestors alive. If I eat much of any vegetable, I have diarrhoea, because the vitamin C in it is too much for the small amount of an enzyme called phenolsulphotransferase that I have. People praise certain supplements like pycnogenol, or drinks like green tea, but I don’t have enough of the same enzyme to deal with them. Yet in times of drought, my ancestors may have benefitted from being able to use vitamin C so efficiently. Now that so many people have dental fillings containing mercury, so many have had vaccines with mercury preservative in them, so many eat tuna, which may contain much mercury, and many mothers transferred a lot of their mercury into their babies, most people need a lot of vitamin C. Vitamin C binds to mercury, so that we excrete it. Those fighting nasty viruses, like flu, polio, HIV, and presumably Ebola, need very high doses of vitamin C, as do those dealing with radioactivity, especially those cleaning up after the disaster at Fukushima. Unfortunately, medical organisations are unlikely to provide much vitamin C, if any. Vaccines are supposed to have brought down the death rates from infectious diseases, but graphs show this not to be the case. Death from infection dropped in parallel with deaths from scurvy, extreme vitamin C deficiency. As the population consumed more vitamin C, people were better able to resist infection. The American settler population soared, after the Irish brought the habit of eating potatoes rather than wheat and rye, as their staple food. People with poor activity of an enzyme called paraoxonase are susceptible to heart disease, and also to organophosphate poisoning. Farmers have been too ill to harvest their crops, because of dipping their animals in organophosphates. If dipping livestock on windy farms, it is difficult to protect yourself entirely from such chemicals. Presumably the enzyme has some other function, because heart attacks and organophosphates were hardly major problems in the Stone Age, when much of our chemistry evolved. Food families Some people avoid particular families of foods. If you avoid potatoes, tomatoes, peppers, chillies, and aubergines, you are avoiding the different alkaloids in these foods. However, there are phenols in green and brown tea, cocoa, kale, blueberries, apples, onions, red grapes and wine, and in some herbs, drugs and disinfectants. Avoiding one family of foods will not avoid phenols. Indeed, no one can avoid them altogether. It is a matter of keeping the total exposure down, if you are sensitive to them. It is actually more complicated than that, as people who cannot cope with phenols are likely to have a problem with amines as well, and they come in chocolate, mature cheese and fish and meat that are not very fresh. Some people can eat happily at a Chinese restaurant, but others react badly to the monosodium glutamate in much food in these restaurants, especially in the soup. Others may seem to cope, but too much monosodium glutamate may lead to motor neurone disease later on. Glutamic acid and glutamate, aspartic acid and aspartate, and cysteine are excitotoxins, which overexcite nervous system cells, even causing some of them to die. Using aspartame at the same time as monosodium glutamate will cause more damage. N-acetyl cysteine (NAC) is used in treating HIV, mushroom poisoning, paracetamol poisoning and flu, but some people have high levels of cysteine, and taking NAC may increase their risk of motor neurone disease. Magnesium is protective against excitotoxins, but it is deficient in many in Britain. Genetic malfunctions A few people are born with disastrous genes, that do not work, and which lead to severe illness and early death. In most cases genes do work, but not all of them well. It may be the interaction of several of these inefficient genes that makes us ill. For example, if you have five of the genes that increase susceptibility to auto-immune diseases, like multiple sclerosis, you have only an average risk of such disease, but if you have eight of those genes, you are likely to develop one or more auto-immune diseases. Some healthy people are now taking tests to look at their genes, to see whether they are likely to develop certain diseases. We have lots of genes, and we can expect problems somewhere. If people receive reports of these polymorphisms, they may just be afraid, and testing will have harmed them. If however they realise that they have genes associated with cancer or heart disease, and change their lifestyles, cutting down on sugar and milk, and eating vegetables, than the testing will have been worth doing. For example, people with BRCA 1 and 2 polymorphisms are more likely to develop breast cancer. BRCA means BReast CAncer. However, breast cancer was much less common in the past, when people ate less sugar, and did not take birth control pills and HRT. Polymorphisms in genes involved in an enzyme called MTHFR make heart attacks more likely, but countries where they consume less milk sugar have much less coronary heart disease. Biochemical individuality People vary a great deal in how their bodies deal with foods, herbs and drugs. This is called biochemical individuality. Advice has to be for the individual. For some while, paediatric clinics have looked at certain biochemical oddities in children. It is only recently that the NHS has set up half a dozen clinics to look at such issues in adults. We are all different. Our genes are different. The environments of our grandparents and parents affect us, and the environment in which we developed. Our lifestyles are different. No wonder we do not all thrive on the same diet, we do not all tolerate the same chemicals, and drugs that work for one person do not work for another. It is an illusion to think that there could be one lab test or machine that could tell you what foods you can eat. It is all far more complicated than that. Margaret Moss MA UCTD, DipION, CBiol MSB MBANT February 2015
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