Jambo, I'm Julia.

Food for Life is a great reference book for understanding what foods to include in your daily diet. The book is divided into two main sections: (i) why the food we eat matters and its impact on our gut microbiome; (ii) an in-depth look into all of the main categories of food and drink we consume, and their impact on our health and environment.

Main ideas

Gut Microbiome

• I like to think of the gut microbiome as a beautiful garden, which has all of the necessary elements to blossom into a diverse and colourful oasis. The food we eat forms the soil for our microbial garden, specifically so-called prebiotic foods; the fibres and other non-digestible food components (including some fatty acids, long sugars like those in breast milk and polyphenols) that act as food for the microbiome, stimulating growth of our existing gut bacteria. The microbes themselves we can think of as seeds, which will only be able to thrive if the soil is ready and rich. A healthy, thriving microbial garden will then have flowers, leaves and lush grass, all releasing oxygen, water vapour and other chemicals into the garden’s microclimate. Many of the chemicals are created by our microbes themselves and are known now as ‘postbiotics’.
• By interacting with and fermenting our food, microbes can control the rate at which both fat and sugar are absorbed into the body as seen by the spikes in our blood and the way they affect our metabolism. Whatever your starting point, having a diverse range of microbes and a good ratio of good to bad bugs means you can eat the same amount of carbs or fats but have less harmful effects.
• When a particular microbe species runs out of its food supply, it will send out signals to the brain asking for more.
• We share roughly 99.7% of our gene variants with each other and are on average fifth-cousins. But we only share around 25 per cent of our gut microbe genes.
• We all have individual responses to different foods – no two people respond in the same way, not even identical twins. Our response to foods depends on several factors, but is more influenced by our unique microbiome than our genes. Amending your diet can alter your gut bacteria and thus change your response to foods, stress, moods as well as helping weight loss and reducing inflammation.

Taste

• Taste is an imprecise term often used interchangeably with flavour, which is a combined food experience.
• Some foods, including apples, have chemicals that provide a key characteristic called astringency. It is neither a taste nor a smell but a tactile sensation of puckering or drying of the mouth and tongue.
• There is a common myth that we have super-specialised receptors for different tastes in different areas of our tongues.
• The key to taste is not my tongue but my nose.
• Most ultra-processed foods (UPFs) contain mixtures of fat, salt and sugar in quantities that have been tested on human volunteers to produce the perfect bliss point which lights up the pleasure centres. The brain, once tricked, then produces feel-good neurochemicals like dopamine which override any signals of fullness from our gut hormones or even our microbes.

Plants

• Plants inherited this skill from algae, who in turn inherited it from some clever bacteria about three billion years ago that had mutated to produce a chemical similar to chlorophyll, which is now found in all plants.
• The different parts of a plant all have different roles and contain varying mixes of both nutrients and chemicals to protect it. The fast-growing leaves or the tips of the young sprouts need the most protection, and so have the highest concentrations of polyphenols. They also hold the most flavour compounds, which is why we often use these tips as herbs to enhance our food.

Vitamins

• In winter, underrated natural sources of vitamin D are oily fish, egg yolks and sunbathed mushrooms (especially shiitake and button), as well as fortified foods. The levels of vitamin D are generally not affected by cooking.

Healthy vs. unhealthy eating

• Healthy eating tips
  • Foods that are good for your health are also good for your gut microbes.
  • Eat plenty of plants and a variety of them. I recommend aiming for thirty different plants per week.
  • Select plant foods high in the defence chemicals called polyphenols, and fibre.
  • Eat fermented foods regularly.
  • Eat foods in their whole, natural form to maintain the optimal matrix, and avoid UPFs.
• The context of how the food or drink is consumed can also be important in deciding if it is ‘unhealthy’. Having a glass of high-sugar orange juice with your meal, or a block of chocolate afterwards with your coffee, will likely do less harm than having it on its own as a mid-morning or late-night snack. This is because although the calorie intake is the same, the sugar spikes and dips will be much greater when the food or drink are taken as a stand-alone snack, resulting in greater hunger levels in the next twelve hours and consequently overeating.
• Top five unhealthy foods
  • Ultra-processed foods (UPFs) – with extra fat, sugar and salt as well as other preservatives and additives.
  • Artificial sweeteners in foods or drinks.
  • Highly refined carbs – these are usually UPFs and low in fibre.
  • Foods that produce high blood sugar and blood fat peaks after meals with a lack of natural matrix or fibre.
  • Snacks containing a lot of sugar or low-quality fats – even if they have ‘healthy’ labels saying they contain protein or ‘natural’ sugars.
• Making better food choices
  • Labels and certificates can be misleading.
  • None of us is good at estimating risks of food choices. Companies can easily produce data and papers to falsely claim their product is ‘healthy’ and back it up through marketing.
  • Food fraud is rife and increasing: much of our food is not what it seems.
  • Knowledge of seasonality can help us bypass the labels and enjoy a varied and nutritious diet.

Immune system support

• Eat fermented foods, which contain helpful probiotics.
• Eat foods rich in a variety of prebiotic fibres, such as leeks, onions, artichokes, cabbages.
• Eat foods rich in polyphenols, such as colourful blueberries, beetroot, blood oranges, and nuts and seeds.
• Eat foods that dampen any inflammation after meals such as green leafy vegetables.
• Reduce consumption of meat and non-fermented dairy to occasional meals.

Food storage and cooking tips

• Frozen or canned fruits and vegetables can retain nutritional value and are good options to access out-of-season foods and reduce food waste.
• Storing, heating and consuming foods exclusively from plastics may not be a good idea – glass, ceramics and wood are safer.
• Many vegetables are better cooked lightly, and avoid boiling vegetables unless it’s for hearty soups.
• Cook at home as often as possible with whole, unprocessed ingredients using good-quality extra virgin olive oil.
• Fermenting is a great way to preserve foods and enjoy added flavour and probiotic benefits.

Big agriculture and environmental considerations

• Perhaps pesticides somehow weaken the plant by reducing its need to produce as many natural chemical defences, a bit like stopping exercise and watching muscles wither. Another possibility, with some data to back it up, is that nitrogen fertilisers used in conventional farming force plants to focus their energy reserves on growth at the expense of polyphenol defences.
• Eating for the environment
  • Buy (and freeze) more fruits and vegetables in season.
  • Eat a greater variety of beans and legumes (that fix nitrogen).
  • Reduce red meat consumption to once or twice per month and make it high-quality, local and organic.
  • Buy less cow’s milk and fewer milk products, focusing on fermented milks and traditional cheeses.
  • Buy more organic fruits and vegetables.
  • Grow some vegetables and herbs in my garden.
  • Make plants the main component of every meal and learn more recipes.
  • Reduce food waste by buying less, more often and locally and making soups and smoothies with leftovers.
  • Compost food waste to enrich the soil in my garden.

Future food trends

• Locally grown, seasonal fruits and vegetables will return to our kitchens.
• We will soon be eating meat, fish and fungi protein grown ethically in labs.
• Meat and dairy replacements will continue to diversify with greater environmental awareness.
• Individual diet scores from new tech and AI will replace governmental guidelines and shape our food choices to suit our personal biology.
• It will be essential to modify UPFs so that they don’t cause us harm.

Fruits

• Apples are an underestimated source of a fibre called pectin, which is thought to be an important factor in healthy weight maintenance and perhaps even weight loss. An apple a day has been estimated to have a similar health impact to taking a statin.
• Pears have slightly fewer polyphenols than apples but are a good source of fibre including pectin and are low in sugar. As usual the skin (and core) is worth eating providing ten times the polyphenols of the flesh.
• Quince is a distant relative that is hard to eat raw because of very high levels of tannin polyphenols, but when cooked these colourless polyphenols transform both colour, taste and aroma to a beautiful red with pigmented carotenoids.
• When dried, plums become the famous prune. They are mass produced by rapidly dehydrating ripe plums in hot air tunnels, which conserves very high levels of polyphenols and the fruit’s dark colour, so they don’t need additional sulphur preservatives.
• In contrast to the usual colour rule, white-fleshed peaches have greater total anti-inflammatory polyphenol levels than the yellow-fleshed ones, although newer red-fleshed peaches beat both of them.
• The mandarin, the pomelo and the citron were probably the original citrus fruits from India and China.
• Limes are a cross of a citron and mandarin and are the most acidic of the citrus fruits, (8 per cent citric acid), lemons are a cross between a sour orange and a citron, with around 5 per cent acidity, the orange is a pomelo-mandarin hybrid, and the grapefruit, with its distinctive astringent naringin chemical, is a pomelo and orange mix.
• Though not topping the vitamin C or the total polyphenol charts, grapefruit are high in anthocyanins and lycopenes, particularly in the recent red-fleshed mutations from Florida and Texas. Grapefruit consumption has been shown to reduce blood pressure in at least three human trials.The hundreds of polyphenol chemicals in grapefruit can also alter the effects of over eighty-five medicines by disrupting the enzymes that normally break them down. While a few medications become less effective, most become far more potent, especially immune, heart and lipid medications as well as painkillers, sedatives, even Viagra. They also make a shot of caffeine go further.
• Drinking a large glass of orange juice is like eating roughly twelve oranges per day, but without much of the fibre and extra polyphenols from the white pithy part of the fruit.
• The raspberry family has the highest fibre content [of berries] because of their high number of seeds, and includes a whole range of hybrid berries derived from crossing blackberries or raspberries, such as loganberries, boysenberries, etc., all with very similar beneficial properties.
• Avoid strawberries with a white ring at the base. These are deliberately picked unripe for decoration not taste; but unlike fruits like peaches and bananas, however long you wait, they will never ripen.
• As a group, berries average nearly ten times more antioxidants than other fruits and vegetables (fifty times more than animal-based foods). It is not surprising that they have earned a reputation as a superfood.
• This suggests that blueberry juice could be the perfect pre-exam breakfast;
• Kiwi is best eaten raw; like pineapple, heating releases dangerous protein-digesting enzymes that damage other food ingredients and can cause a nasty rash.
• Another sleep aid with better evidence is sour cherries (also called Montmorency cherries). These bright-red acidic fruits lack sugar, so growers needed to find other uses for them. They naturally contain melatonin whose primary function is as an antioxidant, but also initiates sleep in mammals.

Vegetables

• Even with pseudo vegetables that are actually fruits – tomatoes, aubergines, or peppers – pick the darker-coloured varieties, although generally, yellow is usually a better bet than green. So go for colour, although beware, there are always exceptions to the colour rule. The two main asparagus varieties, green and white, are similar but the white ones are grown covered by soil so they never gain the green pigment. Purple asparagus is grown with limited sunlight. In my view, all are delicious if cooked precisely. Studies show that all these plants are healthy, but there are large differences in polyphenol counts, with the greatest levels in the green ones, exposed most to the sun.
• As well as the leaf colour, the anatomy of the vegetable provides clues to potential nutrients. In the lettuce family, opt for loose-leaf varieties, with frilly or coloured edges, over the tightly bunched ones. In general, the more tightly-packed leaves near the centre of the plant need less defences, thus contain less antioxidants. In lettuce, for example, this can vary 100-fold from the outer leaves to the centre, so think twice before you discard too many of the tatty darker outer leaves.
• Kimchi, like sauerkraut, is symbiotic as it is a combination of a prebiotic and a probiotic, providing us with both the live microbes and the fertiliser to sustain them.
• In contrast to sauerkraut, however, which contains just five to twelve main bacteria, there are at least twenty-five species of beneficial microbes or yeast in kimchi, feeding off the fibre, sugars and polyphenols. Kimchi is usually a wide mix of vegetable ingredients, and each family has its own recipe. This means that all the vegetable chemicals potentially interact with multiple different microbes to produce multiple new chemicals and metabolites, making it impossible to pinpoint any key ingredient or metabolite.
• The members of the allium family – onions, spring onions, leeks, chives, garlic – contain large amounts of pungent sulphur compounds which they extract from the soil. They are released from the damaged plant cells on cutting or chopping, with eye-watering effect, and get steadily milder with slow cooking (but not with microwaving). While more nutrients are liberated from the chopped and cooked item, it is a good side bet to also ingest some raw alliums for chemical diversity.
• Onions are an important source of inulin, also found in bananas, Jerusalem artichokes and garlic, which is associated with a plethora of benefits for our gut microbiome. Eating inulin every day is likely to be beneficial for overall health.
• We [the UK] are not the world’s leaders in crisp eating, however. The Americans, based on revenue figures, consume three times more per head, and the Canadians double, probably because of those massive jumbo-size bags. While the Japanese are also fond of crisps (wasabi flavour) and come quite close to us, in Europe, the French surprisingly beat us in total consumption – paprika and grilled chicken are particularly popular across the channel, as well as ‘coq au vin’ and ‘chips à la truffe’ (truffle). Brits will usually eat crisps as an additional snack between meals, while the French generally only eat them as part of an aperitif.
• Tomatoes are originally a warm climate fruit and lose their flavour permanently when kept in the fridge.

Legumes and pulses

• Studies suggest that we can extract 20–50 per cent more polyphenols if we mix a squeeze of lime and its vitamin C with our beans, which many cultures have been doing for centuries.
• Eat plenty of peanuts during pregnancy and breastfeeding, and include them in early infant feeding to help avoid allergy.
• Make your own hummus using tinned chickpeas, tahini paste, garlic, olive oil and a squeeze of lemon.
• Eat legumes dried, canned or frozen: they retain nutritional value and are environmentally beneficial all year round – just make sure they’re thoroughly cooked.
• Chickpea, lentil, soy and pea proteins offer a plant-based, sustainable, environmentally beneficial and versatile alternative to animal proteins.

Grains

• Grains are just a particular type of hard, dry seed that comes from cereal plants like grasses.
• Bulgur wheat retains more nutrients than refined wheat and is made from a hard wheat variety that is precooked in water before being dried and crushed (cracked) to form tiny brown grains that are easily cooked by boiling in two to three minutes. It is the equivalent to parboiled rice.
• After the nutritious fat-laden parts of the grain are removed, corn grits are superheated in pressure cookers for several hours. The resulting mash is then rolled flat and toasted. The result is mainly toasted starch whose nutritional value is only minimally better than cardboard, necessitating the addition of multiple fortifying chemicals and high doses of vitamins.
• This effect on blood fats appears due to a special fibre in oats called beta glucan which lines the gut wall with a slimy layer and so reduces fat absorption. Other studies have shown that the more purified and processed the oat glucan, the less well it works. Oats are not unique and barley, shiitake mushrooms and seaweed also contain this beta-glucan fibre. This fibre may also act directly on the gut microbes, stimulating them to produce bile acids and break down fats more rapidly. This benefit on blood lipids is relatively small but could be useful long term. To get any proven beneficial effects of beta-glucan you need 3–4g per day, which equates to one and a half cups of regular oatmeal and a massive three sachets of instant porridge oats.
• The ten most common breakfast foods in the US all contain detectable glyphosate levels, but oatmeal has by far the highest levels. This means that regular porridge or muesli eaters have tenfold higher blood levels of particular chemicals like glyphosate (or Roundup, see page 85). A 2016 UK monitoring program also highlighted breakfast cereals, with glyphosate present in most samples purchased, and the highest levels found in supermarket porridge. Roundup is so ubiquitous that we should take even weak evidence of its harmful effects on our body and microbes and cancer risk seriously, especially if we consume large amounts of oats daily.
• Spelt is a great source of proteins (9–14 per cent) including all nine of the essential amino acids in the right balance. It also has more fibre than other grains (5–7 per cent), alongside plenty of nutrients like iron, folate, manganese zinc and the usual B vitamins. It also provides some omega-3 fats.
• Head to head with quinoa, spelt is nutritionally pretty similar, with less fat and more starch; it has the same good balance of essential amino acids. Although it loses out marginally on protein content and amount of nutrients, it gains by having an even higher concentration and diversity of antioxidant polyphenols, which you notice from some astringency on the tongue.
• Unless you have coeliac disease, choosing gluten-free products is likely to negatively impact your gut microbiome.

Rice

• Usually pre-cooked and processed foods lack nutrients or add unhealthy chemicals, but rice is the exception: the Huzenlaub method actually retains nutrients from the bran husk, so that unlike polished white rice, it has around 80 per cent of the nutrients of brown rice.
• Brown rice has much more fibre than white rice and a better glucose profile.Risotto rice is a great vehicle for vegetables: use a sofrito base and plenty of vegetables and herbs when making yours.
• To save stirring time, rinse your rice in a sieve and collect the starchy water in a pot below and add it back to the rice.
• Eating rice every day can cause weight gain and blood glucose peaks, but eaten occasionally it can be part of a healthy diet, especially when enjoyed with a range of whole plant foods.
• White rice comes in many forms, with softer starchy and stickier types often causing more blood sugar problems in those that are predisposed to them.

Pasta

• Durum wheat pasta is a high-protein food with around 13 per cent protein.
• Couscous is a highly refined fast-cooking pasta more likely to spike your sugar levels – opt for the wholegrain version or go for a whole grain like bulgur wheat.
• Noodles can be made from wheat, buckwheat or refined plant starches and are softer, usually causing more sugar peaks.
• Pasta can be a healthy part of our diet, especially as whole wheat or as a vehicle for plant-rich sauces.
• Some wheat alternative pastas such as chickpea, spelt, buckwheat and lentil are more environmentally friendly and can be healthier, but they are harder to cook well.

Bread

• The term ‘wholemeal’ is the only one properly covered by UK law (and most EU countries) and states that the flour used in the process must contain the two parts of the kernel of the seed (germ and bran).
• To be called ‘wheatgerm’, bread must have some processed wheatgerm added back in, equalling at least 10 per cent of the dry matter of the bread.
• Bread is a good source of fibre and protein but can cause sugar spikes.
• Many bakeries and supermarkets now reheat frozen loaves up to a year old.
• Choose rye, wholegrain and mixed-flour breads with added seeds for fibre and variety.
• When buying bread, pick a low carb:fat ratio and a simple ingredients list.
• Where possible, make your own or buy slow-fermented sourdough bread.

Fungi

• A mushroom is the fruit of a fungus, full of spores that get their nutrition from substances like sawdust, grain, straw or wood chips rather than the soil, before being pushed above ground by a vast network of underground filaments.
• Mushrooms are a rich source of chemicals which play an important role in protecting human immune cells against diseases, such as cancer.
• Mushrooms and fungi should be a larger component of our diet, providing vitamin D, protein and fibre and no downside.
• Magic mushrooms appear as effective as antidepressant drugs.
• Truffles are a rare fungal treat that are best eaten fresh in thin shavings full of complex aromas.
• Replacing 30 per cent of traditional burger meat with mushrooms or fungi would be the equivalent of taking 2 million cars off the road.

Meat

• Red flesh contains higher amounts of iron and myoglobin pigments and is made up of the key long distance muscles, with extra nutrients and flavour, but it is tougher to eat. For most people white meat includes poultry, veal and pork, and poultry can include duck which has dark red meat. White flesh has less myoglobin and fewer nutrients and is more tender but less flavourful. Active humans are mainly made up of red muscle, which help us run marathons; pigs, in contrast, don’t run far and are mainly white muscle, and chickens, as they sometimes cross roads, are a mixture of both, with their dark legs in constant use, while their white breasts or wings are hardly used at all.
• When vegans were persuaded to eat meat their TMAO levels did not change much. This was because they did not have enough resident microbes which could process the original waste products. This suggests we should be wary of too much protein, but having the occasional piece of unprocessed meat may be perfectly healthy, if we leave most of the room in our diets for plants.
• There is little evidence that occasional good-quality meat consumption is associated with poor health outcomes. On the other hand, cheap processed meat products are definitely bad for our health.
• Reducing meat intakes, especially beef and lamb, can have major impacts on global warming and on your health if replaced with diverse vegetables.
• Meat as we know it now has changed drastically since the mid-twentieth century. Modern intensive farming practices do not produce healthy, nutritious or ethical animal meat.
• Meat alternatives and lab-based meats are part of our future.

Processed meat

• Regular processed-meat consumption is associated with increased heart disease and probably cancer.
• Not all processed meats are the same; traditional methods are less likely to be harmful compared to modern fast methods using chemicals, emulsifiers and artificial flavours.
• Ready meals, frozen nuggets and other meat products are made with poor-quality ultra processed meat. Nitrites are not the main chemical to worry about: a cocktail of chemicals is what we need to avoid.
• Beware buying ‘100% natural chicken breast’: if it doesn’t look like a part of the original animal, it’s probably processed.

Fish

• Unless you are pregnant or recovering from a heart attack, overhyped omega-3 is not a useful supplement.
• Half the fish we buy is fake, so check the origin and invest in good quality.
• Eating two portions of fish per week is not needed for health and is not sustainable.
• Most fish we buy are farmed fish that use twice as many smaller fish to grow so are an environmental and ethical disaster. Use accredited labels and websites to help you choose wisely.
• Fish stocks will run out in most parts of the world within twenty years if we continue to fish at the current rate.

Other seafood

• Most British people believe that scampi swim happily in the sea. In fact they were created in a food lab as a mix of deep-fried breadcrumbs and unwanted langoustine tails (also called Dublin Bay prawns) in the 1960s. Now the cheaper varieties of this ultra-processed food contain very little, if any, langoustine and are mainly scraps of other white fish like the tasteless Vietnamese pangasius catfish, bound together with a dozen other chemicals, flavourings and dyes and moulded to make them look like real prawns.
• Crab sticks contain no crab and are just fake, dyed, mashed, malleable farmed white surimi fish with crab flavourings and chemicals.
• We know virtually nothing of the potential risks of humans accumulating plastic in our intestines, but we do know more how our gut microbes will respond. Research on mice fed microplastics have shown that the microbes change to become more inflammatory and with a poorer immune response.3 What we don’t know is whether the microplastics or even the smaller nano plastics we eat are more harmful than the many plastic fragments already in the air we breathe. One scientist estimated that we breathe the equivalent of a credit card of plastic into our lungs each year; a 2022 report confirmed that in eleven out of thirteen people having surgery, plastic was detected in the deep part of the lungs.
• Many prawns and other seafood are farmed in non-sustainable ways.
• Oysters and mussels are a good source of protein and nutrients, sustainable and good for the planet.
• Farmed fish is used for UPFs, and scampi are not real seafood.
• Microplastic pollution is harming our fish and probably us humans too.
• Seaweed is a food of the future with plenty of nutrients.

Dairy

• Many governments and doctors recommend adults drink up to a pint a day for bone health. The latest data is clear and simply doesn’t support this. A study following over 200,000 women with 3,500 fractures showed no protective effects of milk.
• We stupidly believed we could just process the milk industrially to remove the fatty layer, and this would leave all the healthy stuff behind. The fat-soluble vitamins and nutrients get eliminated when you remove the saturated fat content, including vitamins A, D, E and K as well as healthy fatty acids like omega-3 which grass-fed cows will have high levels of. This is another good reason children should not have low-fat milk.
• Comparing different animal milks at the very primitive macro level, human milk is one of the sweetest, has relatively less protein, but the biggest fat globules. Dairy cows produce three times more protein and 30 per cent less sugar, with about the same fat content on average as humans. Sheep, buffalo and yak milk all have more fat than most cows, while goat is slightly lower in fat content. As a low-fat alternative, try camel milk which has a cheesy savoury taste, or horse milk which has only 1 per cent fat.
• Drinking cow’s milk boosts growth but is not necessary for children with adequately diverse diets.
• Choose organic, grass-fed and whole milk, but be aware the environmental cost.
• Cream alternatives are increasingly common but beware of excessive chemicals and palm oil.
• Butter has no health benefits, but is tasty and most alternative spreads are likely worse for us.

Yogurt and kefir

• The fermenting process and presence of live microbes means it is different to milk in many subtle ways, such as a failure to trigger mTOR pathways involved in growth and cancer, discussed in the last chapter.
• As low-fat yogurt uses skimmed milk, fat-loving vitamins are removed and have to be artificially replaced, begging the question, why bother? As long as your yogurt is natural and alive, it’s OK. Avoid low fat, unless you prefer the bland taste, extra chemicals and carbohydrates.
• The microbiome diversity of the regular yogurt users was significantly greater (i.e. healthier) than non-users and they had reduced visceral fat. We had previously found different microbe families (streptococci, lactobacillus and bifidobacteria) that were not in original yogurt were significantly increased. But more importantly, we found many chemical metabolites in the blood and stools of regular yogurt users produced by microbes. These same metabolites appeared to be protective against developing internal belly fat. So, we think that eating the probiotic microbes in yogurt regularly encourages greater diversity of our gut microbes, and these microbes then produce a wider range of healthy metabolites that in turn help regulate our weight and metabolism. We know about prebiotics and probiotics, but this is perhaps a new era of the ‘postbiotic’ as we learn to harness the healthy chemicals that our microbes produce. We showed this may also be the way that microbes via omega-3 fats can help heart health in our twins.
• Flavoured yogurts, fromage frais and fruit or sweetened yogurts are not healthy and should not form part of children’s daily diet.
• Live yogurt and fermented products like kefir support our immune system via our microbes. Natural live yogurt and kefir are generally good for health but we need to be mindful of their environmental impact via milk production.
• Kefir and cultured milk products are rich sources of healthy probiotics and easy and cheap to make at home.

Cheese

• Depending on the microbes in the starter culture and atmosphere, levels of acidity and moisture reached at the point of moulding and the speed at which this happens you will have a very different cheese type. British cheeses like cheddar or stilton are typically acidic and low in moisture; soft French camembert is low in acidity and high in moisture; alpine cheeses like comté are dry but have low acidity; and smelly runny epoisses is both acidic and moist.
• Traditional artisan mozzarella is made with high-quality milk from herds of local buffalo that is transformed into delicate milky cheesy ovals with relatively low fat levels (17 per cent), and is best eaten fresh with an acid like balsamic vinegar or fresh tomatoes. Although buffalo mozzarella is now made around the world and all over Italy, the top product is called Mozzarella di Bufala Campana which is made in a (DOP) protected area of southern Italy.
• Feta is an ancient salted Greek cheese, mentioned in Homer’s Odyssey, made from sheep’s milk (or up to 30 per cent goat’s milk). It is made in the normal way then mixed with salt in several stages, usually lying in a tub of brine with 7 per cent salt for several weeks. Salt encourages the right microbes to grow and up to twelve varieties of healthy bacteria have been detected that protect the cheese. Hard varieties are considered better quality than soft, and it has plenty of equivalents around the world. To be called feta it needs to come from Greece, and most others are called white cheese.
• There are thousands of different types of cheeses, containing varying amounts of fats.
• Traditional cheeses are a rich source of live microbes, protein, calcium and vitamin D.
• Cheese contained in ready meals, burgers, frozen pizzas and some cheese snacks is ultra-processed analogue cheese and confers none of the health benefits of the real thing.
• Raw-milk cheese can be enjoyed safely if properly stored, and supports artisanal, probiotic cheesemaking in its traditional form.
• All cheese has a big environmental footprint related to the large quantities of milk and water used.

Dairy alternatives

• Iodine is key to normal brain development and most teenage girls in the UK who avoid milk are now iodine deficient, potentially impacting the reading age and IQ of their future children.
• Alternative iodine sources to milk include seafood, seaweed, eggs and prunes.
• Plant-based ‘milks’ generally don’t contain as many calories, proteins and vitamins as cow’s milk, and are often highly processed.
• Vegan cheeses are a mixed bag, and while nut-based products have some health benefits, starch-based ones do not.
• The dairy industry has adverse environmental impact, so finding more sustainable alternatives is important, and fortified plant milks and vegan cheese, although not perfect, seem to be an evolving solution.
• Fake butters, although variable and improving, are not beneficial to health.
• Eating high-quality extra virgin olive oil, or smaller quantities of butter or homemade buttermilk, is a better option.

Eggs

• Older eggs, depending on storage, don’t always need to be discarded. They can still be used for baking when over seventy days old or several weeks past the expiry dates. Most supermarket eggs can sit around for one to two months in the system and even longer in your fridge.
• As a normal egg ages, the air will increase in pockets at the wider end and the egg becomes more alkaline. If in doubt, don’t use the expiry date on the pack: put your egg in a pan of water and, like the old medieval test for witches, if it sinks, keep it – and if it floats, throw it away.
• Current estimates place eggs as the least damaging form of animal protein, producing 2.1kg of CO2 per 50g protein, or per egg. Per 50g, tofu weighs in at about 1kg and beef a whopping 17.7kg of CO2. So, while eggs definitely have a smaller climate footprint than other animal proteins, plant-based foods, especially pulses, are still better for the planet.
• Eggs are a great source of nutrients, containing over 100 types of protein and all of the essential amino acids and multivitamins.
• Choose organic eggs from chickens who have plenty of access to the outdoors – they should have a clear transparent egg white when cracked.
• An egg a day is not harmful for your heart or general health, and many people can handle more.
• Eggs are the most environmentally friendly form of animal protein if you eat three to four eggs per week, but they still require billions of caged chickens and the systematic culling of male chicks.

Sweets

• Honey produces a similar effect on the body as table sugar, but it may help tickly coughs and hay fever thanks to its active ingredients. Some human studies have shown that ingesting locally sourced honey can significantly improve hay fever symptoms. It seems that honey might well have anti-allergy benefits. The best theory is that it has an anti-inflammatory effect, and that it may also be presenting the local pollen allergen in a way that allows our gut microbes to recognise it as a harmless protein, thus avoiding an itchy nose.
• It takes twelve worker bees their entire lifetime to produce just one teaspoon of honey.
• The world’s best-loved chocolate spread, Nutella, has around fifty roasted hazelnuts per jar (its production uses a quarter of the world’s hazelnut supply), 58 per cent sugar, 10 per cent saturated fat and very little cocoa.
• When we extract glycyrrhizic acid from the root to make liquorice sweets in their processed glory, beneficial effects decrease and the resulting processed product could be lethal. Chronic liquorice ingestion is associated with increased blood pressure and a drop in plasma potassium levels, with reports of daily liquorice addicts dying from sudden cardiac arrest.
• Dark chocolate has large amounts of polyphenols and fibre and is good for your gut. Look for the high-quality dark chocolate bars with only three or four ingredients. Most commercial chocolate bars are highly processed with dubious ethical credentials – pick high-cocoa varieties where possible.
• Beware of the many sugar aliases on food labels.
• ‘No added sugar’ products can contain sugar alcohols or sugars by other names, which are not necessarily good for us or our gut microbes, or artificial sweeteners, which may have a negative impact on our metabolism.

Nuts and seeds

• People who ate one portion (28g) five days a week had a roughly 20 per cent reduced risk of heart disease compared to non or occasional eaters. They also looked at types of nuts, with some evidence that walnuts were very slightly more beneficial than nuts in general, though introducing nuts and seeds to our diet overall seems to have beneficial effects.
• Walnuts have come out in many studies as being particularly healthy, and the Harvard group estimated that taking occasional handfuls of walnuts conferred the same benefits as regular mixed nuts.
• With seeds, milling them makes their nutrients easier to absorb, but studies show that nut butters do not confer the same benefits as eating whole nuts, and minimal processing is crucial, allowing the nutrients to stay intact.
• It’s hard to have too many nuts and seeds, ideally in their unprocessed form.
• There is reasonable evidence that both seeds and nuts have health benefits against heart disease and cancer.
• They are increasingly being used as vegan dairy alternatives and are a great source of protein and healthy oleic acid fats.
• Eat a mixed variety of nuts and seeds to boost your weekly plant intake. Keep a jar of mixed seeds and ground-up nuts to hand and add to yogurts and smoothies, sprinkle onto salads or into baking dough.

Herbs and spices

• The spiciness of the dishes correlated with the average temperature of that country. That was not surprising, but they also correlated the spiciness of the foods with the predicted number of disease-causing microbes killed by cooking with the spice. This suggests that we have evolved a love of spices because we survived infections by eating spicy food.
• Table salt is refined salt with small even grains that usually contains 2 per cent of other anti-caking chemicals such as magnesium carbonate or sodium alumina-silicate to stop it clumping. It is often ‘iodised’ to help prevent thyroid deficiencies and mental retardation.
• Different countries vary widely in their salt additives, and nearly half of French table salt also contains fluoride to help reduce tooth decay, as they don’t generally add it to water; Germany and Hungary also offer fluoride varieties. Other countries add some dangerous sounding (but approved) chemicals like sodium ferro-cyanide or folic acid and iron. Kosher or kitchen salt, preferred by chefs, is a purer form of table salt without additives and with larger irregular granules, so a pinch is a third less concentrated (and salty) than table salt. Salt is best added from a height (and a flourish) to the pot or food so it disperses evenly.
• Sea salt, if unrefined, has a much wider surface area and irregular crystal structure. It contains several minerals like calcium and magnesium and can contain algae and sometimes a fishy smell. It is good for adding to plated food where these subtle differences can be picked up by the tongue, but is much more expensive and wasted when added to the pot.
• Black peppercorns are unripe berries left in the sun to ferment (thanks again to microbes) and then dried out and left to wrinkle. Green peppercorns are unripe berries that are not allowed to dry, and white peppercorns are just the peeled inner fruit of the soaked black whole peppercorn which slowly turns red when the husk is removed.
• Rosemary and thyme, being quite dry leaves, are easier to package and transport without losing too much of their essential oils and chemicals. Basil, parsley and coriander probably retain more of their benefits eaten fresh. To keep dried herbs fragrant for longer, store them in a cool area in airtight containers as exposed most will lose their magic within six months.
• The exact quantities needed are uncertain, but as a guess, taking 2tsp turmeric per day is worth doing if you suffer with arthritic pain, and probably as an addition to chemotherapy.
• The trigeminal nerves of the face and tongue are responsible for a dual role of detecting burning as well as cool sensations. The capsaicin in chilli affects these nerves by releasing a chemical called substance P, which is picked up by a pain receptor, first irritating then numbing the nerve. Psychologists describe deliberately eating hot chillies as benign masochism that releases endorphins. Humans are the only animals apart from birds who can tolerate and enjoy these hot chillies
• Though phenolic compounds seem to remain intact in dried herbs, vitamin C and carotenoid content greatly suffer from drying, but the consensus seems to be that processed herbs are still a fantastic addition of antioxidant capacity for our diets,
• Adding salt to food improves flavour and is not harmful for most people in normal amounts, but regularly eating hidden salt in UPFs should be avoided. With a few exceptions, salt restriction to low levels is not helpful for most people.
• Spices are good sources of polyphenols and added fibre, good for your gut microbes and contribute to your optimum thirty plants a week (excluding salt and pepper).
• Turmeric may have special health properties, though we need better studies to confirm this.
• Adding mixed spice blends to to your food is likely to increase fibre and polyphenol counts and improve your gut microbes, but make sure you replace them every six months for freshness.

Liquids, oil and condiments

• The cumulation of seventy-six epidemiological observational studies based on over a million people suggests that coffee drinking reduces risk by about 20 per cent for heart disease and mortality and possibly diabetes, with the best effects at around three cups per day.
• Spring water is derived from defined natural sources but has a variable composition. Mineral water, on the other hand, is defined as coming from ‘a source’, but in addition has to have a minimum mineral or electrolyte content (total dissolvable solids greater than 250 parts per million).
• High blood fat that hangs around rather than being cleared efficiently leads to local inflammation and oxidative stress which is bad for our blood vessels. Whilst all fats will cause a blood fat change, those that have high levels of antioxidants (or polyphenols) like EVOO will help to combat the associated inflammation.
• Another good tip is to find the EVOOs that have their vintage on the label – the more recently the olives were pressed, the better the polyphenol content and the lower the peroxides.
• There is no need to drink eight glasses of water a day if you are not thirsty.
• Bottled water is no better than tap water in most high-income countries.
• Soft drinks containing sugars or artificial sweeteners are virtually all unhealthy.
• Coffee and green teas are fermented plant products that have real health benefits. A cup of coffee contains more fibre than a glass of orange juice.
• Alcohol is harmful for most people, except in very small amounts or as a single glass of red wine.
• Extra virgin olive oil is the best oil for cooking and dressing food.
• Most mass-produced condiments, including ketchup, mayonnaise and pickles, have no benefits and their extensive ingredients lists include excessive salt, sugar and additives.
• Worcestershire sauce has powerful umami flavours and thus is great for accentuating ingredients when used in moderation.
• Tabasco is a fermented condiment, and is another good way to add flavour.
• True fermented pickles like sauerkraut, kimchi and traditional preserves made with minimal processing are great for your gut.