Do you get cravings when you aren't hungry? Are you finding it hard to lose weight? Do you have an energy crash at 11am or 3pm? We think of these things as normal. Despite eating "healthily", I definitely didn't know how to get off my own daily energy rollercoaster.
BiochemistJessie Inchauspé has the answer. In her new book, Glucose Revolution, she explains the new science of why controlling glucose levels has a powerful effect on both our health and well-being.
Our bodies weren't designed to eat the high-sugar, high-carb processed modern diet, Inchauspé says. Put simply, during digestion, all carbs turn to glucose, the body's main fuel. Glucose triggers the release of insulin, which stores any excess as fat. And a big input of glucose – a spike – leads to an insulin spike. "Keep doing this day after day, and over time, you risk developing prediabetes, then diabetes," as well as other insulin-related conditions such as polycystic ovary syndrome (PCOS).
Glucose spikes also provoke generalised inflammation in the body, the root of most of our diseases of ageing, plus diabetes, heart disease, obesity, cancer and Alzheimer's. "Three out of five people will die of an inflammation-based disease," Inchauspé says.
Not only does keeping glucose steady help reduce the risk of these conditions, it also irons out the symptoms mentioned above, such as cravings for sugar and energy slumps. Those who follow Inchauspé's methods also report better sleep, hormone levels and skin. And of course the holy grail, healthy weight loss.
Glucose control is an emerging area of research: "Eighty per cent of the studies in my book came out in the past five years," she says. Originally from France, she has a maths degree from King's College London and a masters in biochemistry from Georgetown, Washington DC. Her skill set allowed her to turn the research papers into a series of "glucose hacks" to keep your levels in a healthy range.
The hacks are not a diet. You don't change what you eat, only how. "Keto and low-carb diets rely on the same concept – they flatten glucose and insulin spikes – but with my hacks, you don't have to cut out all sugars and starches. Nobody wants broccoli for their birthday."
Cake and healthy weight loss? It's no wonder that Inchauspé now has over 370,000 followers on Instagram. "When we focus on steadying glucose, weight loss happens naturally, without calorie counting," Inchauspé says. "Studies show that people who focus on flattening their glucose spikes can eat more calories and lose more fat more easily than people who eat fewer calories but do not flatten their glucose spikes."
There are four key biological mechanisms underpinning this natural weight loss. You not only feel less hungry, but you have fewer cravings and you feel more satisfied. Glucose control reduces levels of insulin, the fat-storage hormone, too.
Inchauspé discovered the science behind glucose after taking part in a pilot trial of a continuous glucose monitor (CGM) while working at a health company in Silicon Valley. These were invented for people with diabetes, to allow them to see their glucose levels responding to food in real time.
Jessie shows me her CGM, the FreeStyle Libre made by US company Abbott Laboratories. It's a white disc on the back of her upper arm, around the size of a macaroon. Underneath, a tiny electrode inserted into fat reads the body's glucose levels from the fluid between the tissues. In the UK, the FreeStyle Libre is a regulated medical device that's only indicated for people with diabetes. Each monitor lasts two weeks and costs about £50 (NZ$94).
Inchauspé wasn't diabetic or overweight when she began the pilot. But she did have trauma-related mental-health issues from breaking her back four years earlier, as well as bad skin, poor sleep and afternoon energy crashes.
She decided to use herself as a one-woman experiment, trying out ideas coming from the new research. "As I started playing with the hacks, I'd wake up feeling refreshed. My skin cleared up. I understood what I could do to affect my energy, my mood, my happiness. It was really transformative."
Inchauspé wrote a programme to translate her findings into the graphs that she shares on Instagram. When she began three years ago, her fasting glucose, a standard measure of health, was 5.2mmols/l (5.5 is prediabetic, 7.0 is diabetic). Three years later, it's down to 4.3mmols/l.
Perhaps we'll all become more familiar with our blood glucose levels soon, just as we know our weight. The Zoe programme (joinzoe.com), whose co-founder is Professor Tim Spector, is using blood glucose as one of its measurements in its new personalised eating plan. And it seems likely that CGMs will soon become a common sight on people's arms. In the US, they were first adopted by biohackers for optimising athletic performance, and there are now a few apps that pair with them. Perhaps the biggest uptake will come when the monitors have no electrodes at all and live in our watch; Apple and Samsung are reportedly working on this.
Next month, British app MyLevels will be launched, synched with the FreeStyle Libre. It was founded by Laura Douglas, an AI engineer. You input what you eat, and an algorithm then scores each meal. "It's for people who want to lose weight, but who've tried and failed with diets," says Douglas. People in the testing group have lost up to 22lb (9.9kg) over two months. "But the biggest difference we've seen between this and dieting is that people keep the weight off," she says. It's £150 for a two-week programme.
I wore a CGM for a week to test out Inchauspé's hacks. The day I ate fruit for breakfast, my levels went up and down all day and my cravings were intense. The next day, I ate a savoury breakfast of avocado, then bacon, then a piece of toast (the order matters, see below). It worked: my blood glucose stayed level all day.
There were a few shocks. I'd thought my hot chocolate, made with coconut milk, was a good alternative to eating chocolate. But it made my glucose levels spike as much as half a bar of Green & Black's. The other surprise was wine. I often wake in the night after drinking and the CGM showed me why. After three glasses of wine one evening, my 3am blood sugar was down in the red zone on the glucose graph.
Seeing what's going on inside you is undeniably powerful. When you eat something that causes a blood-sugar spike, see the graph of your blood sugar rise on the app, then feel the slump and cravings two hours later, it really joins up your head with what's going on in your body. And it felt liberating, finally to find a way to dampen down the sugar cravings that have plagued me for years, without having to give up carbs.
• The Glucose Revolution: The life-changing power of balancing your blood sugar by Jessie Inchauspé (Short Books) is published on Thursday
Seven ways to flatten your glucose spikes
Hack 1: Eat foods in the right order
Eat the veggies on your plate first, then protein and fat. And last, any starches and sugars, including fruit and pudding (luckily). A study from Cornell University showed that if you eat in this specific order, you reduce your glucose spike by 73 per cent.
The fibre in vegetables slows both the breakdown of the glucose in your food and gastric emptying. It also creates a viscous barrier in the small intestine that makes it harder for glucose to get into the bloodstream.
Hack 2: Add a green starter
Begin with a salad or any vegetable-based starter, raw or cooked. Jessie suggests: two cups of spinach, five jarred artichoke hearts, vinegar and olive oil. Or sliced carrot with hummus, sliced cucumber with guacamole, sliced tomato with one or two slices of mozzarella.
"In a restaurant, if my party is ordering starters, I order a salad. If we aren't ordering starters, I ask for a vegetable-based side with my main (such as a simple green salad with olive oil and vinegar, steamed green beans or sautéd spinach), and I eat it before the rest of my dish. I wait until after eating my veggies to eat my main or touch the bread."
Hack 3: Eat a savoury breakfast
A study from Stanford University in California showed that when non-diabetics were given a breakfast of cornflakes, it sent their blood glucose to levels that looked prediabetic, some even diabetic.
"A breakfast that creates a big glucose spike will make us hungry again sooner. What's more, that breakfast will deregulate our glucose levels for the rest of the day, so our lunch and dinner will also create big spikes," says Inchauspé.
Your best breakfast is a savoury one: fibre from vegetables or salad as well as protein, such as cheese, smoked fish, eggs, tofu, nuts, nut butter or Greek yoghurt, and optional carbs or fruit (eaten last). "If you're buying breakfast at a coffee shop, get avocado on toast, an egg muffin, or a ham and cheese sandwich."
Hack 4: Watch your snacking
We have been told it's better to eat little and often. But when it comes to glucose levels, it's better to eat larger, more filling meals instead of smaller ones, then snacking in between. Every time you have a snack, your insulin goes up. "When our body is not in the postprandial state, our insulin levels come down and we can go back to burning fat instead of stashing it," says Inchauspé. If you want something sweet, do it at the end of a meal, when it'll cause a smaller glucose spike.
And if you do snack, make it savoury. Good ideas: a spoonful of nut butter; a cup of 5 per cent Greek yoghurt with nut butter; a handful of baby carrots and a spoonful of hummus; a hunk of cheese; apple slices with cheese or nut butter; a hard-boiled egg with a dash of hot sauce; a soft-boiled egg with salt and pepper; lightly salted coconut slivers; seeded crackers with a slice of cheese; a slice of ham.
Hack 5: Vinegar before you eat
Put a tablespoon of vinegar in a tall glass of water, and drink 20 minutes before to 20 minutes after eating. You can use any vinegar but apple cider is the most palatable. If you don't like the taste, start with a teaspoon and work up, or put vinegar in the dressing of your green salad or vegetable starter.
By doing that, "cravings are curbed, hunger is tamed and more fat is burnt". The acetic acid in vinegar slows down the release of glucose into the blood and speeds the uptake of glucose in the muscles. In a study of dieters eating the same restricted calories for 12 weeks, the vinegar group lost 11lb (4.9kg) while the others lost only 5lb (2.2kg).
Hack 6: Put some clothes on your carbs
This hack is for real-life eating when you haven't got time to plan or don't have much choice. "It's for those times when we're going to eat a slice of cake for breakfast because we're hungry and it's there."
The solution is, "Instead of letting carbs run around naked, put some 'clothes' on them," says Inchauspé, ie combine them with fat, protein or fibre. "Clothes on our carbs reduce how much and how quickly glucose is absorbed by our bodies. Have the brownie at your friend's place, but ask for Greek yoghurt with it, too. Have the bagel at the business meeting, but choose the one with smoked salmon in it. Buy a take-out lunch, but add ingredients from the nearest food shop to it: cherry tomatoes and some nuts."
Hack 7: After you eat, move
Move within an hour after a meal and your muscles use up the glucose that's just been released into the bloodstream, flattening any potential spike. Studies have shown this with a 10- to 20-minute walk, weights and strength training, but any exercise is likely to be good. "I've found that I have to do about 30 squats to see any change to my glucose level," says Inchauspé.
Glucose Goddess swaps
Porridge with honey > Porridge with nut butter, berries and chia seeds Fruit smoothie > Smoothie with protein powder, spinach, nut milk, berries, nut butter, cacao nibs Apple crumble > Apple crumble with Greek yoghurt Fruit juice > The whole fruit Pasta > Pasta with chicken and cream Bread > Bread with ham and cheese Chocolate croissant > Ham and cheese croissant Cappuccino with skimmed milk > Cappuccino with whole milk
• If you are worried about prediabetes or diabetes, see your GP, who can carry out simple blood tests to screen for any issues.
Case studies
Dario Traum, climate analyst, 33, lives in London and Paris
I've been following the Glucose Goddess Instagram account since the early days, after I heard about it through a friend. I liked her advice straight away, because she takes a scientific approach, and all her hacks are data-driven.
I put on weight when I was 12, after I broke my arm, although I'd lost most of it by adulthood. Aged 30, I weighed 15st 3lb [96.6kg]. I am 6ft 2in, which made my BMI nearly 27, classed as overweight. And I was conscious I could put on more weight.
I lost my father at the end of 2019, to prostate cancer, and that felt like the right time to focus on getting healthier. I realised that if I kept going with some of my habits, I'd eventually be at risk of developing a chronic disease. The first Covid lockdown gave me a good opportunity to work on this.
Using Jessie's hacks, I've lost just over a stone [6.4kg]. I'm now at the upper bounds of healthy BMI, at just under 25. My doctor told me I'm in the range I should be. It's not perfect, but what's good is that I've sustained that weight for nearly two years.
Before, I'd go through phases of trying to exercise more, but none of those attempts lasted. Now, I've got much better energy in the mornings, and that's playing out in the rest of my day, too. I'm more focused at work, and more motivated to work out.
One of the first things I did was give up my sugary breakfast of bread with butter, or a croissant and orange juice. My parents are German, so I've moved to my German roots by having a savoury breakfast: tomato and cucumber, ham, cheese or eggs.
If I'm about to go out for a big meal, including dessert, and I haven't done any other exercise that day, I do the online Scientific 7-Minute Workout. In restaurants, I've found it pretty easy to make sure my starter is always fibre-rich, such as roasted vegetables with tahini or a seasonal salad. I haven't come across a restaurant that doesn't do a green salad. I now pretty much always have greens both before and alongside what I eat, even when it's pizza.
I enjoy cooking, and it's easy to find dishes that work with Jessie's hacks in Mediterranean and Middle Eastern cuisine, but I'm sure it is in other cooking traditions, too. I love throwing together some marinated vegetables, green leaves, tuna, feta, pine nuts and whatever herbs I have in the fridge into a big salad that works as a main course. If I use apple cider vinegar in the dressing, that's two hacks in one go. After all those fibre-rich greens, I know that if I have a chocolate mousse afterwards, the impact on my blood sugar level won't be as bad.
I drink my apple cider vinegar (ACV) with sparkling water, as it tastes better. My Iranian friends tell me that it's traditional there to have a spoonful every day. Be aware: there are 50 shades of ACV, some are way more bitter.
Overall, I feel more in control. I don't apply all the hacks all the time. But that's one of the good things about Jessie's approach – she doesn't say you have to do everything.
Sima Kumar, CEO, 51, lives in London
I have lupus, and diabetes runs in my family, so since my 30s, I've tried to stay healthy and avoid eating sweets or many carbs. I am certified as a yoga teacher and I was a size eight all my life, but even so, my blood-sugar tests put me in the prediabetic category.
Then in 2020, during lockdown, I got sepsis, from an infection that started due to a coil. It's extremely rare. Afterwards, my body changed. Not being able to exercise, I put on weight. I'm only 5ft 1in, but even size 12 clothes felt too small. I had no energy and my joints hurt. I began to suffer from excruciating period pain, too. Tests showed I had stage 4 endometriosis, even though previously my pain had been manageable. I was put on Zoladex to treat it, which lowers oestrogen and puts you into menopause.
Despite eating as I had before the sepsis, I kept putting on weight. I bought some bathroom scales and found I was 10st [63.5kg], my heaviest ever. I found the Glucose Goddess Instagram and started doing her hacks. Within two weeks, I'd lost inches, I was in less pain and had a lot more energy. Three months later, by last September, I was back to a size eight and down to 9st [57.1kg].
I'm originally from Canada and have a sweet tooth, so I used to love a sweet breakfast, pancakes or toast. But now, following the Glucose Goddess advice, it's always savoury. This morning, I had salad and avocado, followed by rye toast with Marmite and some berries.
I invested in a CGM, too, to see which of Jessie's hacks worked best for me. Apple cider vinegar in water before every meal was one real game-changer for me: now, even if I'm going to a restaurant, I'll take a little bottle of vinegar with me. The other one was going for a 10-minute walk after I ate.
Now, I can eat carbs and I don't put on weight. Tonight, I'll eat mushroom risotto, but I'll have apple cider vinegar in water and a green salad first. For dessert, I've made a vegan chocolate mousse with berries.
Jessie says no food is good or bad: it's how you eat it that counts. She explains the science behind cravings, so that if I want a vegan Magnum or some Ben & Jerry's, I don't feel bad. I love that I haven't felt deprived; I'm never hungry and I feel so energetic. But best of all, last time I went to the doctor, he told me that I'm no longer prediabetic.