Why this 20-minute rule will stop all cravings

Distracting yourself for 20 minutes may well be enough to quell that mid-afternoon biscuit craving
Distracting yourself for 20 minutes may well be enough to quell that mid-afternoon biscuit craving

Ever found yourself fighting to focus on work, only to find thoughts of sweet, velvety chocolate floating up into a mind? Normally you’ll find that there is only one way to get back on track: caving to the craving. Or is there? One school of research, and even some NHS guidance, suggests that the urge could dissipate if you just hold out for twenty minutes. It’s all down to the way our brains are wired.

“We get a rush of pleasure and an anticipation of reward when we see, smell or are in the presence of tasty foods,” says Charlotte Hardman, Professor of Psychology of Eating Behaviour at the University of Liverpool. Researchers have gone to great (and sometimes amusing) lengths to investigate the origins and power of that rush, including, Hardman explains, piping the scent of chocolate into MRI scanners. Reward centres in their brains light up in response to the smell. It is likely, explains Hardman, that the mere thought of food can trigger opioid and cannabinoid receptor sites in our brains. When these are stimulated, they produce a powerful desire otherwise known as… a craving.

Why you crave more when you’re stressed

Yet the success with which you wrestle that craving might come down to another, competing system in your brain. Because while your reward system seeks out pleasure, your cognitive control system is trying to control your impulses and help you make more logical choices (put down the cake, in other words, and push on with the blasted report). It is, Hardman suggests, rather like a cowboy trying to train a wild horse: “There’s a push and pull between these systems, and which system wins depends on an array of other factors, like how tired you are currently feeling, or how stressed.”

This is why, for some people, waiting for 20 minutes can be a useful indicator of whether you are genuinely hungry, suggests Dr Emily Leeming, registered dietician at King’s College London whose work explores the impact of food on your mood. If your desire is rooted in hunger, you will still feel the need to eat after that time has elapsed. But if, as is commonly the case, your craving is actually rooted in emotion or stress, twenty minutes may be just enough time for it to subside. Especially if you spend the time doing something to tackle that stress.

“Could you go for a walk, and might that make you feel better? Or listen to music or call a friend,” she suggests. Since food can activate our reward systems, it does often have the power to improve our mood, she says, and sometimes, that is a great thing. But eating should not be your only strategy when you are feeling low: “it’s about having lots of different tools in our emotional toolkits…”

Dopamine drives desire

Especially since, as Hardman stresses, cravings are a pretty complicated phenomenon involving a web of different brain messages and chemicals, learnt behaviours and emotional associations. For example, while the smell or sight of a treat is activating the neurons in your reward system, a chemical called dopamine is also being stimulated in the brain. Dopamine is often called the ‘pleasure chemical’ but this is actually something of a misnomer. What it actually does is drive your desire for things that you associate with pleasure.

In other words, this sudden surge in dopamine, triggered by the expectation of a treat, fuels your craving for it. But here’s the good news. The surge is likely to be relatively short-lived. Kent Berridge, a neuroscientist at the University of Michigan and leading dopamine researcher has previously suggested that surges peak at around five minutes (another study suggests elevations, in animals at least, might last “minutes or tens of minutes.”).

So, if you only cleared your lunch plate a short while ago, but the cake in the fridge is calling you, then put a twenty-minute timer on and distract yourself or, better yet, de-stress. It may well be enough to quell that craving, put your cognitive control system back in the saddle, and keep the cake in its box.

Beat your cravings with these easy swaps

Instead of morning coffee, have a herbal tea

Do you wake up, open your eyes, and crave coffee? If you have had a bad night’s sleep, downing coffee before breakfast can actually send your blood sugar levels haywire for the rest of the day, making you feel tired and potentially plagued by more cravings, explains Leeming. But how can you resist? Rituals are a really important component of our attachments to particular foods and drinks, says Leeming. Take coffee. A large part of its impact can revolve around the fact that it’s part of a ritual, where you sit down and start the day with a rare moment of calm and clarity. You can build those same habits around a cup of herbal tea instead.

Besides, much of the power we attribute to the things we crave is in our heads. Leeming points to a study in which Type-2 diabetics were all fed exactly the same drink, some from a bottle advertising it as high sugar, some low. “The blood sugar levels of those who believed they were drinking a high-sugar drink rose as if they really were,” she explains.

Beat the 4pm sugar slump by going for a quick brisk walk

Fingers itching to reach for the biscuit tin as you crawl towards the end of the working day? Consider trying the trendy dopamine diet, based largely around the consumption of more protein. Since protein is made of amino acids, which are key to the production of dopamine, at least one study has suggested it can up your levels and reduce cravings for the snack drawer. Otherwise Hardman points out that taking a brisk, 15-minute walk has also been shown to reduce cravings for sugary snacks.

Swap sweet treats in front of the TV for prunes and dark chocolate

Want to curb your evening chocolate cravings? Do not ban them. The findings of one study, suggests that doing so only results in stronger cravings for the taboo food. “Behavioural science shows us that we’re not very good at simply stopping something without giving ourselves a good alternative,” says Leeming. Instead: “you have to find a really pleasurable and easy alternative. For me, it’s dark chocolate and prunes – high in polyphenols and fibre, and it satisfies that need for sweetness when it arises.”

Replace wine after work with probiotic kombucha

A lot of our cravings are habitual, says Hardman, and it may not take as long as you expect to break the habit of sipping a sauvignon as soon as you shut your front door, and replace it with a desire for a fizzy kombucha instead. It is a probiotic, so has potential benefits for your gut, and it also has a tart, grown-up flavour. Not sold on it? Don’t give up. The human brain forms positive associations between contexts and drinks pretty quickly. Hardman points to one study in which people were fed milkshakes while looking at specific images on computer screens. It took just six sessions for those images to start stimulating a desire for milkshake.

Ditch the social media scrolling and have a cold shower

A cold shower might not sound as tempting as a crossing through Facebook, but bear with us. In her book Dopamine Nation, the Stanford University psychiatrist Anna Lembke explains how, since our brains release dopamine when we make connections with other people, the mere thought of opening up that app can result in a surge. One answer, she suggests, is to embrace habits of an opposite nature: things that are not tempting but difficult to begin with, yet which result in a slower, sustained rise in dopamine. Czech researchers, for example, have shown that just a few minutes of exposure to cold water can end up boosting your dopamine levels by 250 per cent. So next time you’re itching to scroll, consider a cold shower instead.

Wean yourself off online shopping with simple meditation

Why is online shopping so addictive? Research from Stanford also shows that the areas of the brain associated with dopamine release are activated when we are exposed to photos of things we want to buy, while another 2014 study shows that shopping can dispel sadness. If stress or worry lies at the root of your urge, consider Hardman’s advice: “mindfulness meditation is something a lot of people find helpful when they are experiencing cravings.” 10 minutes of meditation will also result in your dopamine levels rising, but it will happen steadily, rather than in spikes. It is also, crucially, a lot easier on the wallet.