While the title of this article may at first seem implausible (and somewhat scary), a new scientific study seems to show that an inborn preference for junk food is not only possible – it may be affecting more of us than ever could have possibly been imagined. For the first time in history, researchers for Obesity Society have identified two genetic variants, which help to change how the brain responds to high-calorie foods.1 2 While this is potentially terrible news for those of us who struggle to resist highly processed and manufactured foods – it also means there is possibly a way to stop this genetic variant from controlling our dietary choices. This could include changing how the brain processes junk food, changing how much people crave these foods, and even altering the brain’s dopamine system. There are even more potential treatments using this new information – including using gut hormones to act on dopamine brain cells.
To delve into further detail, researchers specifically found that two genetic variants – FTO and DRD2 – influenced brain activity related to the reward system. This occurred when subjects simply looked at pictures of high-calorie foods. As I’ve written previously, this is far from the first time neuroscience (or other scientific studies) have shown that some of our brains respond differently, to rewarding foods.3 4 5 6 7 8 9 10 11 In early 2014, for example, a study was published which showed that not only did some people crave chocolate (while others did not) – but that there was literally different brain activity, in the two groups.12
Asmaro D, Liotti M. High-caloric and chocolate stimuli processing in healthy humans: an integration of functional imaging and electrophysiological findings. Nutrients. 2014;6(1):319-41.
In another, similar study, researchers found that by altering dopamine receptors (specifically D2 receptors) – they could cure binge eating.13 Unfortunately for us, that ground breaking study was done on rats – not humans. However, this is further evidence that our brain plays a fundamental role in overeating and cravings. In fact, it may be the excess stimulation of the nucleus accumbens (the ‘pleasure center’ of the brain) from junk food, which leads to obesity.14 15 16 17 18 19 20
How does this relate to our current world? Well, 70% of the United States is overweight, with 30% of us now being obese.21 What accounts for all these extra pounds? Certainly, as shown by research from Yale scientists, a hyper-stimulatory environment and excess advertisement of junk food – is a large part of the problem.22 23 24 But this data is compounded by other research, which shows that extended access to high-fat and high-sugar food, results in behavioral and physiological changes – which are similar to those caused by illegal drugs.25,26 While a large portion of these corresponding studies were conducted on rats, this does not mean that the results will not translate to humans. Like many areas of scientific research, we simply need more data.
Baik JH. Dopamine signaling in food addiction: role of dopamine D2 receptors. BMB Rep. 2013;46(11):519-26.
As I’ve covered previously, the neurobiology of sugar addiction is fascinating as well.27 28 The brain is bombarded with an overwhelming amount of chemicals and reward, when you consume junk food.29 30 31 32 Over time, this leads to a higher quantity of junk food needing to be consumed, to achieve the same rewarding effect.33 34 35 So even for those of us who are not genetically susceptible to the temptations of junk food, we can alter our brain’s preferences and reward receptors, to become just as likely to crave it.36 37 38 39 40
Gómez-pinilla F. Brain foods: the effects of nutrients on brain function. Nat Rev Neurosci. 2008;9(7):568-78.
The good side of all this bad news? Your brain can also be positively impacted by food.41 42 43 44 45 46 A Paleo diet, which is full of nutrient dense foods, will help keep you satiated, and keep your brain from craving high sugar, nutritionally empty choices. Be sure to load your plate with wild-caught fish (high in brain-friendly omega-3 fatty acids), healthy fats (like avocados) and complete sources of protein (like grass fed beef). You may indeed be hardwired for junk food – but that doesn’t mean you have to give in to temptation. Adopting a Paleo diet is associated with many different health benefits – many of which work to counteract the negative effects of junk food.47 48 49 50 What this means, is that you can improve your health drastically, by simply changing what’s on your plate. Start eating a Paleo diet today, and watch your health soar!
Table of Contents
References
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