We’re all familiar with the lure of a burger.

But what few of us realise is that the urge comes not just from your stomach, but deep inside your skull. According to a US study from the Scripps Research Institute, junk food has the same effect on your brain chemistry as cocaine and heroine, and for some people it can be equally addictive.

“We found that an excess of foods high in sugar and fat resulted in a deficit in the brain’s reward systems, much like drug dependency,” says neuroscientist Dr Paul Kenny, the author of the study. Those foods are tempting because they trigger the release of chemicals that make you feel good, such as dopamine and serotonin. And the more you get that post-gorge high, the more you seek the food that causes it. Eventually, the “neurochemical pattern” of all-you-can-eat junk makes the urge for that fix hard to resist. The result is that you become addicted to crap.

That’s the bad news. The good news is that there’s a way to regain control without going cold turkey. The key is to supply your brain with the same reward triggers, but from activities and foods that aid your fitness and weight-loss plans. Rather than over-stimulating your brain, these beneficial rewards are released steadily and, in time, you will become addicted to healthy things instead.

Find out why junk food is so addictive

Help is on hand from Dr Mike Dow, an addiction specialist and author of Diet Rehab. His pain-free plan is designed to help you overcome a reliance on unhealthy food, without having to swear off it for life.

Nobody can go from Homer Simpson to Ned Flanders in a day. We know this. Nor is there any need to make that change for good. The key is to strategically cut the crap over four weeks, says Dow. “You replace junk with healthy alternatives that stimulate the same feel-good brain chemicals.”

In the first week, all you have to do is swap one item of junk food for something wholesome and do one “booster activity” a day. This includes exercise, which triggers the same reward system in your brain as food, but anything that makes you feel good afterwards will do the job.

“Write a note to a friend, take a look at some old holiday photos or start planning your weekend,” says Dow. If you can work some competitive action into the mix, then all the better. A study at the University of Southern California showed that engaging in competition – even if it’s just a game of poker – causes a spike in your dopamine levels.

In the second week, include two food swaps and two boosters a day. In the third week, you include three, and so on.

For example, a piece of chocolate cake could be replaced with a bowl of multigrain cereal and berries, plus booking your next trip away. Cheeseburger urges can be satisfied with some beef jerky and a run along a new route.

If at any stage you feel yourself struggling, try to rate your level of hunger out of 10. Remember, these urges start in your brain, not your stomach, so unless you’re at seven or above – that’s genuine hunger – fight back.

And now that the sun is shining, you can also try bathing your cravings in sunlight. A study in journal The Lancet showed that serotonin levels in healthy adults are directly correlated to the amount of sunlight in the day. That means the more light you get, the less junk you want.

The longer you use these methods, the easier it becomes. “Eventually you remove yourself from the negative cycle of eating bad foods, overstimulating your brain and needing more and more to get the same hit,” says Dow. “You’ll start to associate healthy foods with reward and will have a much better balance of brain chemicals.” In other words, you’ll be a health-food junkie.

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