Put clothes on your carbs

“When we eat naked carbs, such as plain pasta or a slice of cake, the glucose molecules arrive really quickly into our bloodstream uninterrupted, causing a big glucose spike,” says Jessie Inchauspé, author of Glucose Revolution, who kickstarted a conversation about balancing blood sugar for optimal health.

Delivering too many starches (pasta, rice, oats, bread, potatoes) and sugars (anything sweet, from an apple to a cookie) to the bloodstream at once triggers a glucose rollercoaster of craving and crashing every two hours. Glucose spikes increase inflammation in the body and trigger mitochondrial stress. “When your mitochondria (the organelles responsible for making energy) become overwhelmed, they don’t make energy as effectively, leading to exhaustion, poor sleep and cravings for more sugar,” Inchauspé says. The brain is a heavy consumer of glucose and hypersensitive to spikes, which have been linked to increased anxiety and depression (if you have a medical history of them), brain fog, irritability and being “hangry”.

You can fix this with a simple hack Inchauspé calls “clothes on carbs”: adding protein, fat or fibre to slow down glucose absorption. “A bowl of pasta is naked carbs, but if you add spinach, chicken and olive oil, you’re adding protein, fibre and fat which will slow down the speed at which the carbs are digested and the glucose arrives in the bloodstream, reducing the spike.”

The same principle can be applied to all starches and sugars. “If you have a slice of cake, add a dollop of yoghurt and some almonds (protein and fat). The same goes for beans and rice, or grapes with cheese. Whole fruits are fine to eat naked because fruit contains fibre, but adding ‘clothing’, such as almond butter with apple slices, helps reduce spikes.”

Keep it bright and bountiful

The brighter your plate, the more nutritious it will be, so if in doubt, eat the rainbow. “The good news is gut microbes are not driven by genetics, so we have the power to improve them through a gut-friendly diet and lifestyle,” says Tim Spector, epidemiologist, author of Food for Life and co-founder of personalised nutrition programme Zoe. This is less about volume, more about variety. “Eat a diverse range of fruit and veg – I recommend 30 different plants a week. That includes coffee for me, as it’s a fermented bean,” Spector adds. “Pick plants that taste bitter, are brightly coloured and high in polyphenols [natural defence chemicals our microbes use as fuel]: berries, nuts, seeds. A red pepper is more beneficial than a green pepper and a purple carrot has nine times more polyphenols than an orange one.”

For Nick Mole, policy officer at Pesticide Action Network (Pan UK), cleaning up the fruit and vegetables we eat requires structural change. “The UK is one of the countries with the lowest percentage of organic farmland in Europe, so there should be more support from the government. We should be following the model of France’s Farm to Fork plan which aims to reduce the use of pesticides by 50% by 2030.” To shop smarter, Mole recommends checking the Pan UK website for supermarket ranking and a “Dirty Dozen” list of fruit and veg with the most pesticide residues on them. Top five in the latest research are peaches/nectarines, grapes, strawberries, cherries and spinach.

Start savoury

Rethink your morning pain au raisin and apple juice, because although a sweet, starchy breakfast gives us pleasure (it releases dopamine in the brain), it also kickstarts a glucose rollercoaster for the rest of the day. “It’s like having a chocolate bar first thing in the morning on an empty stomach – two hours later you’ll crave something else sweet, and you’ll have cravings every two hours until you go to bed,” Inchauspé says.

The good news is you don’t have to quit sugar altogether; just eat it at the right time. “Dessert is not for breakfast – it traditionally comes after a meal and now, with modern science, we understand why.” Inchauspé swears by a savoury breakfast to keep energy levels steady throughout the day. The key thing is to make protein the main ingredient, not sugar or starch. Eggs, Greek yoghurt, cream cheese, meat or tofu should keep you full for four hours. Add fat (avocado, chia or flax seeds, olive oil to scramble the eggs) and fibre (spinach, tomatoes or mushrooms) where possible.

“If you’re going to have something sweet, eat it after the savoury food, not on an empty stomach, and stick to whole fruit, which contains fibre and tends to be consumed more slowly than juices and smoothies,” Inchauspé says. “Many of us drink apple or orange juice or smoothies marketed as ‘100% fruit’, so we think we’re making a healthy choice when actually it’s like drinking a can of Coke.”

DIY your fast food

“Frozen pizzas are very different from a sourdough pizza covered in mozzarella – the kind that’s been eaten in Italy for more than a thousand years,” says Chris van Tulleken, an associate professor at University College London and author of Ultra-Processed People. “Even a burger doesn’t have to be unhealthy; it’s the industrial versions that aren’t good for us.”

Too much convenience food has left us stuck in what Henry Dimbleby, author of Ravenous and co-founder of Leon restaurants, calls a “junk food cycle”. “We have an appetite that is an evolutionary mismatch, so our system rewards us for going out and finding foods that are highly calorie-dense to give us massive dopamine hits,” he says. “Those foods are low in soluble fibre, we eat more of them and get less full when we do. When you eat food cooked from scratch, you eat lots more fibre and 30% more vegetables, which is beneficial for your gut and immune system.”

For many, ultra-processed foods are the most affordable and available. “Fried chicken from a takeaway shop on the high street costs less but will be ultra-processed, whereas fried chicken you make at home is a perfectly healthy traditional dish,” Van Tulleken says.

Switching from deep frying to air frying could reduce overall calorie intake by 70-80% by using less oil. Similarly, make your DIY pizza work harder by using a wholegrain crust, homemade tomato sauce and vegetable toppings.

Make a Mediterranean kitchen

The fastest way to improve your diet is to cook more meals from scratch. Kimberley Wilson, chartered psychologist and author of Unprocessed, suggests looking to the Mediterranean diet for inspiration: “Go for sardines, because you need oily fish for DHA omega three, choline and iodine for optimal brain health. In Greece, dementia is a low cause of death and that is linked to a higher intake of nutrient-dense wholefoods, herbs, vegetables and seafood compared with the British diet.”

Research shows the Mediterranean diet reduces the risk of cardiovascular diseases, dementia and depression, while raising life expectancy. Primarily plant-based, the diet focuses on healthy fats including olive oil, avocados, nuts and oily fish such as salmon and sardines. Eat fish twice a week, plus small portions of other animal proteins such as cheese, limit red meat and focus on fresh ingredients. “Buy more fruit and veg, batch cook and freeze portions,” says Van Tulleken, who also recommends teaching children traditional home-cooking.

“In the scheme of things, eating food cooked from scratch is more important than eating organic food,” Dimbleby says. “Cooking from scratch with lots of green veg and roughage is a good thing.”

Crowd out the UPFs

“Frozen pizza, microwavable lasagne, flavoured yoghurts, breakfast cereals … if a food is wrapped in plastic and contains at least one ingredient you don’t find in a typical kitchen – such as xanthan gum, flavour enhancers or emulsifiers – it’s likely to be ultra-processed,” Van Tulleken says. “Food manufacturers should put warning labels on certain UPFs. They’re doing it in Chile and Colombia, and it works – put a black hexagon on food and children ask their parents not to buy it.”

UPFs account for 56% of the calories the average person in the UK eats, and a high intake is associated with type 2 diabetes, inflammatory diseases, cardiovascular disease, obesity and dementia.

But a recent World Health Organization-backed study concluded that, while preference should be given to wholefoods where possible, some UPFs, including bread and cereals, could reduce the risks, provided they contain fibre.

For Wilson, the solution is adding more wholefoods to cram out the UPFs. “Hardly anyone is eating enough fruit and veg; it should be closer to eight or 10 portions than five a day. We need B vitamins for brain function, structural fats from marine foods, choline to support the nervous system, iodine to regulate metabolic rate, and 80% of our body’s cellular activity requires magnesium.”

Wilson recommends adding a sliced banana to cornflakes or having leaves with your shop-bought sandwich. “Your gut microbiome needs fibre, so consider wholegrain rice, pasta, beans and lentils. Leafy green vegetables, green tea, a wholefood diet and plenty of fibre also slow down ageing in the brain.”

Feed yourself the four Ks

Poor-quality processed diets, an overuse of antibiotics and living in increasingly sterile environments means we’ve lost nearly 50% of our gut microbe species compared with our ancestors, according to Spector. “We’ve underestimated the gut microbiome but we now know we can’t really survive without our microbes. They provide thousands of chemicals to help digest our food and get the nutrients out, providing key vitamins that support our immune system.”

The gut microbiome affects everything from the body’s ability to fight infection to managing mood and metabolism, and Spector recommends nurturing its microbes by regularly eating fermented foods, including the four Ks: kefir, kombucha, krauts and kimchi. He is also an advocate for intermittent fasting to allow microbes to rest and restore rhythm. “Fourteen hours between meals is ideal for different microbes to come out and give your gut lining a spring clean each night.”

Wilson suggests getting children involved from a young age. “In Korean nursery schools,” she says, “they teach four-year-olds to make kimchi because it’s such an important cultural food. If children have made something, they’re more likely to consume it.”

Take short, sharp shots

It’s the superfood already sitting in your cupboard. Drinking a shot of vinegar before you eat has been shown to help support your gut and immune system, and balance glucose levels. “The acetic acid in vinegar temporarily inactivates alpha-amylase, a digestive enzyme in saliva that breaks down starch, so sugar and starch are transformed into glucose more slowly, reducing spikes,” says Inchauspé, who recommends diluting one tablespoon of vinegar in a glass of water and drinking it through a straw (to protect teeth from the acid) 20 minutes before a meal once a day.

As well as curbing glucose spikes, research shows adding apple cider vinegar before meals leads to reduced visceral fat and lower cholesterol, thanks to its natural antioxidants, and it has a natural probiotic effect that can support the gut and immune system (via the fermented apples). When shopping for apple cider vinegar, make sure it contains “the mother” – a thick, gelatinous layer, or “bits” that give it a cloudy appearance – made of gut-friendly bacteria.

“Apple cider vinegar may be the most popular but all kinds of vinegar have acetic acid, so they can all help flatten our glucose curves, from wine vinegar and rice vinegar to coconut vinegar,” Inchauspé says, adding that it’s best to avoid syrupy vinegar such as balsamic glaze or vinaigrettes with added sugars.

Crunch before you munch

Bringing back the humble vegetable starter will help top up your fibre levels. “Fibre fuels the good bacteria in our gut, strengthens our microbiome, lowers cholesterol and makes everything run smoothly,” says Inchauspé, who recommends eating vegetables before every meal to get fibre into your system early. The scientific theory is that fibre at the start of a meal arrives first, making its way to the walls of the intestines and acting as a mesh to slow down the absorption of glucose molecules that will arrive later in the meal from starches and sugars.

“This isn’t groundbreaking. We’ve just lost touch with these traditional habits,” Inchauspé adds, suggesting a healthy, vegetable-based starter of crudites – raw vegetable sticks of carrot, cucumber, baby corn or peppers, with hummus or guacamole as optional protein and fat – or antipasti, such as olives.

Give peas a chance

A warming bowl of split pea soup, or mushy peas, or baked beans on (sourdough) toast, is phenomenally good for your gut health. “Fibre and beans are so important for the integrity of your gut lining and blood brain barrier that there should really be a national campaign to bring back beans,” Wilson says. “We should be eating 90% more beans. We grow so many fava beans and lentils – it used to be a real staple crop in the UK – but they are somehow looked down on and disparaged. We need to get back to traditional ways of cooking and eating, things like lava bread and home-cooked stews.”

Pease pudding goes back to the middle ages and is overdue a comeback, says Wilson, who likens it to Moroccan hummus. “There’s a dish made with split fava beans and it’s seen as this exotic Mediterranean meze recipe but it’s literally pease pudding. People in the north have been eating this for years. Traditional British food isn’t bad for us, it just needs better PR.”