The mere sight of a slice of gooey chocolate cake, a cheesy pizza, or a sizzling burger can drive us to eat these foods. In terms of evolution we show preference for high calorie foods as they are an important source of energy. We tend to crave these rich, tasty foods not only when we are hungry, but when we are emotional, bored, or stressed out.
Burger picture from Shutterstock
We show a preference for these sugary and fatty foods as they are not only energy dense, but because our brain releases certain neurotransmitters when they are eaten. These neurotransmitters include dopamine and serotonin, which are involved in pleasure and act as reward signals. So the brain reward system is “tuned in” to attend to these sugary, fatty foods, and this leads to cravings that can increase consumption.
However, in a world with an abundance of these highly caloric foods, the rate of obesity is also rising. Combined with increasingly sedentary lifestyles, the old adage “a moment on the lips, a lifetime on the hips” is becoming true for many people who are experiencing weight gain. We know that eating these foods is bad for us. But when we are faced with the choice between a healthy option such as a salad, or a calorific burger served with hot chips, temptation is often hard to overcome.
But what if we could train our brains to desire healthy foods? So after a stressful day at work you crave an apple rather than a chocolate bar. Could you then choose the salad option over a steak at a restaurant, and do so without the nagging pangs of food envy when watching others dig in to their meals?
A recent study has shown some evidence that we can train our brains to want healthy food. A group of overweight and obese adults were shown photos of healthy (fruit, vegetables, lean meats) and unhealthy foods (chips, burgers, cakes) in a functional MRI scanner, which measures the activity in the brain. Brain areas involved in processing rewards showed greater activation when the participants looked at the unhealthy foods, and the participants rated these foods as more desirable than the healthy foods.
Some of the participants then went on to a diet composed of nutritious, low fat, high fibre foods. The diet was combined with counselling to help the participants with lifestyle changes. After 6 months on the diet, the participants had lost weight compared to the no diet control group. Interestingly, when the diet participants were shown pictures of unhealthy foods in the fMRI scanner their brains showed less activity in reward regions. Also, when shown images of healthy foods, their brains showed more activity in reward regions than before they started the diet.
As a scientist interested in eating behaviour and the reward system, I found this interesting. Why would the brain shift preference for palatable, calorie rich foods in favour of healthier options?
Healthy foods are not typically associated with the immediate release of rewarding neurotransmitters. But, for people who have switched their diets from eating the junk foods that lead to obesity, to healthy diets that have made noticeable improvements in terms of weight loss, these diets have become associated with rewarding outcomes. The positive outcomes can be simply fitting into a pair of jeans that are a size smaller than usual, or from complements from family and friends. So choosing a salad rather than a burger becomes a more rewarding option as it has become associated with good feelings.
On the other hand, positive associations between eating fatty, sugary foods can decrease but attributing these foods with negative outcomes, such as feeling uncomfortable in clothes, gaining weight and not being complemented by people anymore. Unfortunately, negative emotions are also linked with increased cravings for comfort foods and can drive overeating, leading to a vicious cycle of emotional eating.
Our relationships with food are complex, and we cannot simply flick a switch in our brain that makes us choose an apple over a cupcake. But for people embarking on a long term change in diet it is important to recognise that we are not slaves to our desires. We might not get the same immediate “kick” out of eating healthy foods, the long term rewards are much more tangible than we might consider at first.
Amy Reichelt is Research Fellow at UNSW Australia. She does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations.
This article was originally published on The Conversation. Read the original article.
Comments
7 responses to “Can You Train Your Brain To Crave Healthy Foods?”
Sure. Get a tomato, a salami, and bread and butter. Slice tomato and salami thinly bulid a single sandwich for lunch.
Actually, smoked or cured meat products are the latest foods to have health warnings issued. Very not good for you. Apparently.
That’s true, though only in larger amounts, a sandwich a day isn’t going to kill you, we are talking about what? 50g?
This seems like a lot of effort… I’d rather expend that energy on eating whatever I want, then working it off at the gym. Mmmm, workout endorphins.
It’s not as simple as calories in, calories out. That is highly out-of-date, incomplete information now. I suggest you read this article to greatly open your mind and hopefully make you realise that WHAT you eat also matters, very much!!
http://articles.mercola.com/sites/articles/archive/2014/04/05/calories-overeating.aspx
Maybe if you’re fine-tuning, but if you exceed either way by a significant margin, the laws of physics take over. You can’t create matter out of nothing. 🙂
(Granted, for a very limited number of people with rare conditions, you can eat practically nothing and their bodies will prefer to consume their muscles and organs before consuming fat, meaning they’ll lose enough weight to kill them without actually being slim, but for everyone else, the rule holds.)
Haha yeah I don’t mean you can get energy from nothing – what I mean is, the health implications of calories isn’t as off-the-hook as, ‘as long as I burn it off, the unhealthiest possible form of calories (say trans fats), is no problem, cos I’m burning it off after all! Do read that article if possible, it’s quite in depth with useful info from studies on the matter discussed :).
Yeah, in my experience, it’s a two-pronged picture / two-fold process:
1. Pull yourself out of the negative cravings cycle – the cravings for ‘bad stuff’. Now, what this Nature paper doesn’t cover, is that actually, a big part of cravings for sugar and refined carbs and other similar unhealthy sources of calories, is actually sourced from ‘bad bacteria’ in the gut (as opposed to ‘good bacteria’, which do a whole host of positive things which if you Google, you’ll be amazed at a whole burgeoning field of scientific research that only now is trickling into the public consciousness in terms of its implications for human health). When you eat bad food (that is proven to significantly contribute to heart disease, diabetes, and many serious chronic illnesses), it makes bad bacteria multiply as they FEED on this high-avaiability sugar provided by all these broken down, processed foods like donuts and burgers and pizza and fizzy drink and other nasties I don’t want to be thinking about. These bad bacteria OVERPOWER the balance of good bacteria, and become the dominant form in your gut, causing not only countless health issues like lowered immune strength and even alarming cognitive issues or effects like increased stress and the like, but these bad bacteria are what ARE CAUSING your cravings for this bad food – again and again. So it’s not even you that are craving it – it’s the bad bacteria in your gut that are controlling YOU! They’ve mapped the mechanism for microbes controlling the brain (or vica versa – it goes two ways) via the ‘vagus nerve’ now, it’s proven and demonstrated and it’s amazing science to behold. So when you start ‘eating right’, and completely eliminating processed, bad foods from your diet (start predominantly eating fresh, whole foods especially including raw or lightly cooked vegetables, and fruit) – your gut microflora changes with this, and they then overpower the bad, and the GOOD ones like lactobacillus and bifidobacteria start being the dominant ones instead. They drive out the bad – it’s nature’s way of balancing itself when you honour how it’s supposed to work! (we weren’t designed to eat Macdonald’s junk!!) I’ll also note here, that one of the little-known advantages of eating organic food vs. conventional – especially in salad vegetables or fruits you eat the skin of – is that commercial chemical pesticides KILL good bacteria on the surface of these fruits and vegetables – whereas with organic, you’re bound to have at least some, and, the closer to you growing it yourself – like try farmer’s markets where it’s even been picked that morning or the day before if possible – there’s LOADS of healthy bacteria in, on, and just below the surface of, your fruits and vegetables, so you can build up strong healthy gut from it! Or, for a more interventionary plan b, take ‘probiotics’ supplements for a bacteria shot in the arm instead.
2. Get yourself in a positive cravings cycle. It seems more mental this one – I don’t myself experience good bacteria ‘screaming’ out for quinoa sprouts or kale salad 😉 – but it’s not ‘hard’ to do it either, once in the positive cycle – rather, it’s just a more mental MOTIVATION for doing it instead of a dangerous, helpless physical out-of-control one in the ‘bad cycle’!
So rather than being on auto-pilot thanks to bad bacteria – it’s a more YOU in control, mental system, of eating motivation! And I say that’s healthier for other reasons anyway, like positive mental health in association with your food and health, so is a win-win!
But as a possible ‘life hack’ to those who aren’t interested in doing all that work to pull themselves out of the ‘bad’ cravings paradigm in the first place – do look up ‘probiotics’ supplements – it’s often in powder form (probably ‘powder in pill form in many cases but same thing)’, and it might just reduce your cravings for unhealthy food and make it easier to balance out how much YOU want to eat anyway, being a pretty cool hack even if I say so myself!
Probiotics is basically concentrated food extracts (from grains, various foods that have the BEST known bacteria in them in a concentrated, and dormant form, ready to activate and proliferate in your gut when you ingest it), and I’ve found it’s also amazing stuff to stop nausea in its tracks VERY quickly too – I’m talking even five/ten minutes max after quite strong nausea (no matter what caused it, it seems). The one I use for moments like these, is this S.A.F.E products living enzymes powder stuff – they’re health food company based in QLD. the stuff actually tastes ok (i.e. not horrible, sort of mild carby, actually pineapple-y flavour), and the best way to take it is to soak a teaspoon full sublingually and around the sides of the mouth (it’ll harden after few minutes but just try to soak it as much as possible), in order for it to enter the bloodstream directly though the pathways around the jaw to then quickly enter your gut. It just. works. wonders!