A Bad Taste
We have since discovered that some of the most prolific consumers of fat in the world, the Cretans from southern Greece, are among the healthiest and longest-lived.
Cubans, despite eating on average twice the total amount of sugar as Americans, are poorer but far healthier.
Our bodies simply seem to adapt to the new reduced calorie intake and do what they are programmed by evolution to do. It appears that the dull monotony of most exclusion diets is overridden by the body’s impulse to hold on to our fat stores. Once someone has been obese for a while, a whole series of biological changes transpire to maintain or increase their fat storage and the brain’s reward mechanisms for food. This is why most diets fail.
Most diets are based on a narrow traditional view or simple observation and quackery, but the massive differences between individuals and their physiological responses to food go unexplained.
Our narrow, blinkered view of nutrition and weight as a simple energy-in and energy-out phenomenon and our failure to account for our microbes have been the main reasons for the miserable failure of diets and nutritional advice.
Microbes
Microbes generally get a bad press, but less than a tiny fraction of the millions of species are harmful to us and most, in fact, are crucial to our health. Microbes are not only essential to how we digest food, they control the calories we absorb and provide vital enzymes and vitamins as well as keeping our immune system healthy.
When you next go to the toilet, spare a thought for your trillions of microbes. Nearly half the mass you are flushing away are microbes.
Intermittent fasting (such as the Fast Diet or 5:2) may be the exception, as short-term fasting can stimulate friendly microbes, but this is only as long as the other, ‘free eating’, days contain a diverse diet.
Fifteen thousand years ago our ancestors regularly ingested around 150 ingredients in a week. Most people nowadays consume fewer than twenty separate food items and many, if not most, of these are artificially refined.
Energy and Calories
This suggests that all calories are not the same. Two thousand fast-food calories will have very different energy consequences from 2,000 calories made up of whole grains, fruits and vegetables.
Also, people with longer large intestines can extract more calories from food than those with short ones, and some studies have shown differences of up to 50 centimetres between populations.
manufacturers are legally allowed error rates of up to 20 per cent on their product labels.2 Many common items, such as processed frozen foods, underestimate calories by up to 70 per cent, and high-fibre products by 30 per cent;
One study even showed that eating white rice with chopsticks rather than a spoon significantly reduced the speed at which the blood glucose rose and triggered insulin
But response to calories also depends on your own physical and genetic make-up and, last but not least, on the microbes in your gut.
Butyrate is a small fatty substance produced by our gut microbes that has many beneficial effects on the immune system, and exercise stimulates microbes to produce more of it.
The bottom line, however, is that although exercise is not of much benefit for your weight or for burning fat (unless you are a professional athlete), it is good for you, your heart and your longevity. And since it also makes your microbes healthier and more diverse, it is a good thing.
Total
We couldn’t exist long without fat, and when deprived of it in the diet our livers will do whatever it takes to make some.
Polyunsaturated fats (sometimes called PUFA) come from natural vegetable oils and are fairly neutral or protective, but the claims that margarines containing them are heart-protective are exaggerated and not backed up by hard evidence.
Trans fats (also called hydrogenated fats) are the worst kind, and as they are totally artificial come only from processed or fried foods. They were initially hailed as the healthy alternative to butter.
proportionally there is nearly three times as much of the lipid cholesterol in ‘healthy’ foods like lobster, crab meat or fish oil as in ‘unhealthy’ lard, beef or pork. Eggs are packed with cholesterol, and many people stopped eating them decades ago because of erroneous advice to avoid cholesterol at any cost. Cholesterol is a complex lipid that is part of virtually every cell in our bodies: 80 percent of it is synthesised naturally inside us and only around 20 percent is eaten as food. As well as providing the protective and nourishing lining to the walls of our cells, cholesterol is a key ingredient of many vitamins and important hormones.
Food fats come in many shapes and forms, some good, some bad and some ugly. So before you routinely reach for the zero-fat labelled items on the shelf it would be a good idea to find out more about them.
Fats:Saturated
Most cheese is made up of 30 to 40 percent fat, and most of this is saturated fat which is traditionally considered the fat to avoid. The rest of the fat in cheese is of the poly-and monounsaturated varieties. Only about 1 percent is actually cholesterol.
Some human clinical trials have shown that cheese supplements could be used to maintain the microbiome in people taking antibiotics, which normally knock out a large proportion of our healthy species.
For French cheeses the key to the many tastes are the other substances that the milky rag may be dipped in – such as, in the past, horse urine, which gave acidity as well as distinctive flavours.
These mites emphasise that cheese is very much alive – a living entity full of microbes – from the specialist milk bacteria, lactobacilli, to yeasts and fungi that are responsible for the tasty blue veins in cheeses such as Roquefort and Stilton.
But it turned out that only about 1 percent of our gut microbes are easy to grow in culture and these are the ones generally harmful to us – pathogens, in other words. New gene-sequencing methods have totally changed the process and uncovered the other 99 percent of species we live with, most of which are never harmful.
After just a day of the cheese diet my gut microbes had started to change, with big increases particularly in a number of the lactic acid bacilli (lactobacilli) and in the yeast penicillium.
The cheese group didn’t increase blood lipid levels or cholesterol at all, whereas the butter group did, showing that not all saturated fat is the same.
The famously pungent Limburger cheese is made from the same bacteria that many people have between their toes (Brevibacterium linens), the ones that cause smelly feet.
His theory was that ageing is caused by rotting toxic bacteria in the gut and that consuming lactic acid (producing bacteria in milk and yoghurt) could counteract this, thus prolonging life.
Despite the ‘unhealthy’ saturated fat and concentration of calories, dairy products could, paradoxically, help us lose weight.
So the consumption of yoghurt microbes alters the way we break down other foods and initiate anti-inflammatory pathways.
Many low-fat yoghurts are full of sugar (or puréed fruit), which could negate the benefits as sugar stops bacteria growing.
In the affected twin’s blood we found altered levels of the key brain chemical serotonin. This chemical comes from our food except when we are fasting, when our gut microbes manufacture it for us.
As discussed earlier, many commercial yoghurts while promoting their low-fat status contain lots of concentrated fruit and sugar or sweeteners which could inhibit the growth or function of many microbes. So avoid these and keep your yoghurt natural and with plenty of microbes.
Fats: Unsaturated
People that really enjoy their food may actually, via their brains, be able to both make themselves feel happier and stimulate their microbes.
Sadly, the truth is somewhat different, and the people reporting to be happiest and most content are the Scandinavians.
Polyphenols actively encourage some microbes to flourish, such as lactobacilli that mop up and bind fat/lipid particles and clear them from the blood. They also prevent unwanted microbes from colonising our guts.
It clearly demonstrates that extra virgin olive oil and nuts taken regularly on top of a basic Mediterranean diet reduces the incidence of disease and early death.
In fact polyphenols are found in a number of other Mediterranean foods: in many brightly coloured vegetables and fruits such as berries, in cocoa nuts, some green and black teas, turmeric and red wine.
Once you ferment these fruits and vegetables as pickles or alcohol, the number of polyphenols produced can increase exponentially.
Trans Fats
Another study showed that a love of junk food in pregnant rats could be passed on to their offspring. It could be transmitted to the babies by subtle (epigenetic) changes switching their genes up or down, or alternatively by maternal gut microbes that got passed on at birth, or via suckling.
The American documentary maker Morgan Spurlock famously went on a total McDonald’s diet for thirty days for his documentary Supersize Me. His cholesterol went up 30 per cent, his uric acid levels (associated with gout) doubled, and the results of tests for liver damage more than trebled. He had a gut ache, sweats and occasional nausea, and after a few days experienced strange cravings, depression and headaches, which were relieved temporarily on resuming eating. By the end of day 30 he had eaten 12 lb of fat, 30 lb of sugar and gained 7 percent of body fat, most of it visceral.
Several other rodent studies have confirmed that high-fat and high-sugar diets produce these inflammatory changes as well as a leaky gut wall, which allows gut microbes and chemicals to pass through into the blood.
When the fat content of the diet increases rapidly there’s a sudden increase in a certain type of bacteria that has a thick protective cell wall. Fragments of these cell walls (made up of lipids and sugars called LPS, or lipopolysaccharide) quickly build up and form an endotoxin, an internal poison that humans are very sensitive to.
This was clear proof that fat-associated microbes are really toxic and can be transmitted like an infection.
So the more poor-quality junk or processed food people eat, lacking in fibre and nutrients, the more signals the body sends to eat more in order to recover those ‘missing factors’, causing a vicious cycle of obesity and under-nutrition.
Protein: Animal
Paleo meals contain plenty of animal protein and are low in carbs, without grains, cereals and most sugars.
For example, our friendly bifidobacteria that we get from yoghurt and that all Westerners have, was totally absent in all the Hadza and most of the Yanomami.
It should be possible, however, to improve the microbiome of a regular meat eater by having a meat/carnitine holiday. In other words, indulging in an occasional steak may not be harmful.
One problem is that there is also L-carnitine in fish. Cod, sea bass, sardines, tiger prawns and squid, for example, have 5 to 6 mg of L-carnitine per 100 grams, though this is only a tenth of the amount in beef which has 95 mg.
switching to organically raised meat may also be a slightly healthier option, as you’d hope it would be hormone-and antibiotic-free and so the animals would have had healthier microbes as well as healthier lives.
Protein: Non-animal
Although most beans have 20–25 per cent protein, soy is the champion at 36–40 per cent.
As we have noted before in this book, the same foods can have very different effects in different people. Even when considering a single soy product, we have found that its effect in Europeans appears different from its effect in Asians.
When you combine the epigenetic effects of soy with other known endocrine disruptor chemicals like bisphenol (BPA), which is in many babies’ plastic bottles, you could be preparing a dangerous cocktail.
Protein: Milk Products
Remember that over 20 percent of people report stomach upsets when taking placebos in drug trials.
According to our combined studies of over 50,000 European twins, height is over 80 per cent heritable (that is, 80 percent of the variation between people is due to genes).
When I visit the hospitals and universities in Holland, I find that most Dutch students still have a large glass of it at lunchtime.
In fact, the microbial contents of raw and pasteurised milk are remarkably similar.
Carbohydrates: of which Sugars
Fructose is the sweetest naturally occurring substance and considerably sweeter than glucose.
My fibre intake was quite good, which might limit some of the damage by reducing the speed of absorption of the fructose and glucose.
If the sugar comes from fruit or another ‘better’ source, it doesn’t matter, because if there is little or no fibre your body treats it just the same.
Dentists’ families, in contrast, didn’t have sugary drinks at night, not even milky ones, and seemed magically never to suffer the same problems, showing that the decay was entirely preventable.
Compared to our ancestors, nowadays we rarely use our chewing powers and jaw muscles to the full, as shown by the lack of growth of our jaws and the subsequent modern epidemic of impacted wisdom teeth resulting from a mismatch of jaw sizes.
When rodents are fed high doses of fructose, it increases their visceral fat dramatically.
Carbohydrates: Non-sugars
Humans have just thirty enzymes to break down all the complex carbohydrates they ingest, but luckily our gut microbes have over six thousand at their disposal to do the job properly.
Fibre
Whereas probiotics are selected microbes that benefit the health of the host, prebiotics are the constituent parts of foods that act as fertilisers for the microbes in the colon.
The first prebiotic we encounter in life comes handily packaged in breast milk and is called an oligosaccharide, which is a complex group of tightly bound sugars.
A healthy person needs about 6 grams of prebiotics a day to keep both their microbes and themselves healthy.
These prebiotic compounds come from natural ingredients such as chicory root, Jerusalem artichoke, dandelion greens, leeks, onions, garlic, asparagus, wheat bran, wheat flour, broccoli and bananas and some nuts.6 The percentages of the prebiotic inulin in each one vary enormously, from about 65 per cent in chicory root to only 1 per cent in a banana.
Garlic, as well as being an excellent source of polyphenols and vitamins, is a first-class prebiotic that used to be a major discriminator between the cuisines and habits.
amylase is in our saliva to break down carbohydrates and in the pancreas for releasing into the small intestine.
For each copy of the amylase gene you are short of, your risk of obesity increases by 19 per cent.
This in turn could lead to more rapid increases in insulin on eating starch, which ultimately leads to predisposed people storing more fat.
Artificial Sweeteners and Preservatives
The carbonation is another factor that can trick the brain into thinking a product is less sweet than it really is. Flat cola is often undrinkable.
Researchers fed rats Splenda (Sucralose) at the FDA-recommended human doses for twelve weeks, and found significant reductions in total microbe counts and diversity, and in particular this affected the healthy microbes.
This elegant series of experiments shows that artificial sweeteners are definitely not a free lunch; they do have potentially harmful metabolic effects that can increase weight gain and the risk of diabetes.
reason for the recent rise of allergies. Most of the chemical safety-testing of food additives and sweeteners focuses on determining the risks of poisoning or cancer, not on detecting metabolic changes.
Contains Cocoa and Caffeine
Caffeine is probably the world’s commonest psychoactive drug, drunk by 80 per cent of the world.
Most of the body’s hormone serotonin is produced in the intestines, and recently we have found it is mainly manufactured by microbes during times when we are not eating. Autism is increasingly and consistently associated with disordered microbes, and these could be the link with abnormal brain-chemical signalling.
Gram for gram, cocoa has the highest concentration of polyphenols and flavonoids of any food, and it’s a precious commodity.
When a British clinical trial gave volunteers the polyphenol extracts (flavonoids) from cocoa for four weeks, it saw significant increases in bifidus and lactobacilli and reductions in the Firmicutes family as well as in markers of inflammation.
The microbes fed off the flavonoid polyphenols and produced many helpful by-products, like the healthy SCFA butyrate. What was striking was that after a week the amount of these polyphenol metabolites was greater than could be accounted for just from the diet. The microbes, once fed a bit of chocolate, were producing these healthy chemicals of their own accord, like little home industries. They also found that regular chocolate eaters had different and healthier metabolisms and microbes than occasional chocolate eaters.
So training your taste buds to eat more than 70 percent cocoa dark chocolate may be worthwhile in the long term. But working out your minimum daily dose is going to be difficult, as actual amounts of helpful flavonoids vary widely according to the manufacturing process.
Caffeine has been linked with increasing stress, poor sleep and long-term heart disease and cancer.
It showed that moderate coffee drinking, three or four cups per day, reduces the risk of death by around 8 per cent and heart disease by 20 per cent. Unlike my own, inferior, analysis, there was no effect either way on cancer.
Contains Alcohol
Asians famously have low tolerance, as they carry a variant of the alcohol gene dehydrogenase, which metabolises it fifty times faster than in Europeans or Africans, who lack that variant.
This experiment suggests that it was the polyphenols in the wine rather than the alcohol that had the greatest effect.
Vitamins
Beta-carotene, vitamin E, and high doses of vitamin A supplements are definitely harmful.
Other antioxidants, folic acid and B vitamins, as well as multivitamin and mineral supplements, are ineffective for preventing mortality or morbidity due to major chronic diseases.
Proper trials, however, show it has no effect in the prevention of colds, or of cancer or any other disease. A few studies have shown that, like zinc supplements, it may reduce cold symptoms by half a day if taken early on, but an orange or some broccoli may do the same.
vitamin loyalty
Studies show that folate can epigenetically switch off some of the protective genes of both the mother and the baby, and in a high dose could be having other effects such as increasing the risk of allergy, asthma and breast cancer.
Europeans who regularly take calcium pills have stiffer arteries, full of calcium deposits. This gives them a slightly increased risk of heart disease and stroke which they were trying to avoid.
However, the truth was revealed recently when a meta-analysis of over fifty trials involving over 95,000 patients taking vitamin D replacements showed no convincing evidence that supplements do reduce death or fracture.
Warning: May Contain Antibiotics
All countries overuse antibiotics, but those with well-controlled centralised health care systems like Sweden and Denmark use the least – proportionally, half of what America uses.
This often begins when a round of antibiotics depletes the natural bacterial flora in the colon, reducing the diversity and power of the usual protective community and allowing a certain aggressiveness.
Remember that the first three years of our lives are the most important in forming our core set of gut microbes whose job it is to maintain our health. Sadly, many drugs are given around birth without any thought for the poor microbes. Giving pregnant mothers antibiotics for mild urinary tract infections is commonplace, and for the last thirty years powerful wide-ranging intravenous antibiotics like cephalosporins have been routinely prescribed for mothers just before caesarean section operations so as to reduce the 1 to 3 per cent risk of post-op infections. This drug crosses the placenta to the baby and affects the breast milk, and may have even worse effects.
In normal deliveries the infant gut is first seeded by microbes from the birth canal, including vaginal, urinary and gut microbes, followed by others from the skin. This produces a rich diversity of starting material for the crucial first three years, when, as noted earlier, the character and complex interactions in the gut are formed. These microbial communities are key to our normal development, and particularly in training our immune system, which has to learn from scratch. Vaginal microbes in particular change dramatically during pregnancy in preparation for the birthing process, and when they are altered can trigger early labour. Babies born via C-section are extracted before they can be exposed to the normal microbes from the traditional evolutionary route.
Nature has perfected the transfer of helpful nutrients and immune signals from the mother to the next generation not just via her genes but also from her microbes, which are finely tuned by what she eats during pregnancy.
The young cattle are rapidly weaned off natural hay and grass and trained to eat mass-produced corn laced with low-dose antibiotics.
Warning: May Contain Nuts
An extra 30 grams of mixed nuts, eaten raw (and unsoaked) in the famous PREDIMED randomised diet study, produced significant advantages over the low-fat heart-disease diet and was nearly as good as the extra olive oil group.
There are many other chemicals in nuts we know little about, such as cachexins which may help with losing weight. If you don’t cover these complex bundles of food in sugar or salt, nuts overall are good for us.
These doctors, who perform hundreds of allergy tests monthly on high-risk kids, say this kind of severe reaction is very rare and never occurs with peanuts transmitted by air. One exception to this is fish allergy because it’s the fish odour that contains the allergenic protein.
However, the opposite is true: that women snacking on peanuts during pregnancy are actually much less likely to give birth to nut-allergic kids than those who abstain.
Licking babies is common in most mammals and in some human cultures, and of course kissing is pretty universal.
Thus was the hypothesis that excess hygiene could lead to modern allergic diseases.
People brought up in less sanitary conditions and regularly exposed to animals and worm infestations never seemed to develop asthma or food allergies. This was believed at first to be purely to do with the immune system, which needed to be stimulated by infections early in life to fine-tune its defences.
One reason the Amish have such low rates of allergy is that they drink plenty of raw unpasteurised microbial milk.
But in terms of microbes, genes and our health we are very close to pigs.
The Checkout
‘Eat food, mostly plants, not too much.’ And to modify another bit of his advice: ‘Don’t eat anything your great-grandmother’s microbes wouldn’t recognise as food.’
I have found that reducing amounts of over-refined carbs (white pasta, rice, potatoes etc.) is beneficial to my health and that replacing them with wholegrain varieties is fairly easy,
Try to eat a greater variety of foods, particularly fruits, olive oil, nuts, vegetables and pulses plus fibre and polyphenols. Avoid processed foods and reduce your meat intake. Eat traditional cheese and yoghurt, avoiding high-sugar low-fat varieties. I like the concept that our ancestors ate in very irregular and seasonal ways, so intermittent fasting or giving up meat for months at a time or skipping some meals seems sensible to enhance your perception of variety.