Exploring the science behind food cravings…
Kale please, Mum!
After my son requested a bowl of kale (with lots of butter, please!) when he was recently sick, it got me thinking about the science behind instinctive eating. Hidden in our intelligent body are mechanisms that initiate cravings for certain foods that our body needs. But judging by the way most people eat, I think we have lost the art for healthy instinctive eating.
I am always fascinated how animals are so instinctive with their food choices – and yet humans seem to need to google for advice about what foods are good for them or maybe they come see a nutritional health professional like me!
So what went wrong? When did we humans stray so far from our innate intelligence about what is good for us to eat? Most cravings we experience now are for the addictive substances like caffeine and sugar! While we all know the damaging effects of too much sugar, the cravings for sugar have do a biological drive behind them. Those hardwired desires for sugar, meant we ate sweet foods when they were available seasonally and they kept us alive and ensured our survival through the lean winters of bygone eras. Unfortunately we have gone overboard on this front as modern life allows us to eat whatever we want, whenever we want. We are no longer at the mercy of nature to provide our food – we are indeed spoilt for choice!
I think the superpower that created us all those years ago, clearly didn’t predict a time when we would be so disconnected from nature and our food supply. The clever system that allowed humans to flourish throughout history with all sorts of hardships, does not seem so clever now when we look at how we have ended up the fattest and most chronically unhealthy species. We were smart enough to develop agricultural methods of growing grains and crops, domesticating animals and eventually creating modern food manufacturing methods of processing and preserving. Clever on the one hand, yes, but our genetics unfortunately takes thousands of years to catch up with a changing landscape, not hundreds of years! So we are now at the mercy of a very different food and eating landscape than we were designed for, and where our fine tuned instincts for certain foods have gone been hijacked by the drive for sugar!
Instinctive eating – essentially means eating what our innate intelligence determines to be good for us. We are all born with the ability, much like other animals, to select appropriate food for our requirements. For example, a craving for bananas may show you are lacking potassium, while a craving for green leafy veggies may indicate you need more magnesium. The term ‘pica’ is used to define mineral deficiencies (often iron) that results in people eating strange things – such as dirt, rocks or ice. Most commonly seen in pregnant women and young children who have a high need for nutrients, pica is the most researched nutrient craving issue. Studies observe that individuals with symptoms of pica often have low iron, zinc or calcium levels. Supplementing with the lacking nutrients can reduce the pica behaviour in many cases. Craving for salt is also more common in those individuals who have low salt levels, so the wisdom of the body to correct the deficiency is obvious.
Evidence also shows that our need to eat certain foods (often unhealthy types) is sometimes driven by emotions. Many people are “emotional eaters” and tend to eat for reasons that are driven by emotions and have nothing to do with being hungry or needing a nutrient. People who craved foods were shown in studies to more likely to be bored or anxious or have experienced a depressed mood immediately before cravings. Several brain imaging studies have shown that overconsumption of certain foods creates the same changes in the dopamine receptors of the human brain as alcohol and other addictive substances.
So all in all, we do not fully understand what is happening in our brains when we crave or consume certain foods. It is definitely a vastly complex process and is attenuated by many different cues coming from social and cultural inputs as much as nutritional drivers. For example, most celebrations have particular foods that are so strongly associated together that we barely question it. What is a birthday celebration without the birthday cake?
The one thing that is worth taking home is to pay more attention! Try to differentiate when the craving is just coming from an old habit or an emotional driver and see if you can notice cravings for healthy choices that might still be available to you. Tune in first, before you eat and see what your body really wants! If you find you are really stuck on an underlying pattern with your eating habits or food choices, remember that there is a lot we can do (such as mind/body techniques like Psych K) to help remove the block and give you more freedom around food, so consider coming in and getting extra help!