A deep understanding of how the brain works is essential in order to limit our health footprint through everyday choices. With a better understanding of impulsivity and short termism we can reorient ourselves to enhance our lifestyles. Modern imaging techniques show the gradual build-up of human brain from reptilian to mammalian to humanoid. At the bottom sits the survivalist reptilian core that serves the vital functions—heartbeat, breathing, body temperature and balance. Survival through crude power and violence without remorse or forethought is its function; it will hijack the body when it sees survival threat. This brain also distastes failures, which in the evolutionary past mostly meant instant death. Mindless violence at the heat of the moment, sudden outburst of anger, or addiction are classic examples of brain hijack. 

In the evolutionary past, when starvation was the norm, mindless binge eating to fill the body with concentrated calories increased chances of survival. To our reptilian brain concentrated calorie is highly satisfying and tasty. In today's world where calorie starvation is exception, not the norm, this tendency has become a disadvantage. Human brains could evolve and adapt over thousands of generations if food abundance continues to be the norm. In the meantime, we face an uphill battle in this era of food factories that can refine food, which appeal to our core brain. This core brain derives immense pleasure from those "tasty" refined foods devoid of nutrient diversity. Fortunately, we can restrain ourselves from falling into this trap by consciously shifting our thinking paradigm and retraining our baby taste buds to like nutritional diversity over refined calories.

Defeatism is perhaps the first thing we need to defeat. Our core brain instinctively brushes off new ideas. To this brain, change seems dangerous: failure is death, success is survival. Our caveman instinct prefers clinging to any shred of evidence or look for exceptions as examples to preserve the status quo, no matter how fragile that evidence is.

Calorie not volume, is how human body goes when it uses energy for daily living. A tablespoon of oil or 2 tablespoons of sugar have the same energy for human body as a cup of vegetables or a bowl of green leaves. We need to rethink; consciously, we need to retrain our thoughts so that a large bowl of vegetables feels like the same amount of food as a cup of milk or rice.

Nutrition per calorie must be today's mantra. We can consider food as calorie vs nutrients. While calorie is essential for short term survival, nutrients are needed for the long term health. Carbohydrate, fat and protein supply energy as calories. Sugar, oil, white rice, white flour, meat, eggs and dairies are largely empty calories; they give us lot of energy without much nutrients. Green leaves, vegetables, fruits, beans, mushroom, onions, seeds on the other hand are nutrient dense, supplying us with vitamins, minerals, fibres, and phytochemicals (plant chemicals). We associate rich food with empty calories, like biryani. Can we not see food as they are in the nutrition value chain: biryani as poor food and vegetables as rich food? Empty calories like sugar, fat, or alcohol dilute nutrition, are weakening the body's protection. Rich food should be rich in nutrition, with high aggregate nutrition density index (ANDI) value. Empty calories are devalued food, poor food, devoid of nutrition.

Starvation needs another dimension today, incorporating twenty first century knowledge. Traditionally, the poor were skinny and starved to death as they could not afford the needed calories. More people die today from over‑eating empty calories than its shortage. Another group of poor emerged with abundance of cheap empty calories in the form of industrial processed food and hectic lifestyle. Despite having enough money they are starving in nutrition.

Retraining baby taste buds has never been so challenging with busier parents, shrinking family sizes, and commercials bombarding our children with poor empty calorie foods that appeal to baby taste buds. Babies need a lot of calories and growth hormone to grow fast in early years. As we grow older, we need more nutrient rich food. Retraining the taste buds is essential, as we do with learning how to walk— through practice and stumbles along the way. Once retrained they will enjoy the rich flavour and texture of nutrition and slow burning fibre rich calories that benefit health. Exposing children to more (nutrition) rich food in early age can help.

Empty calorie addition is another challenge we face. Empty calories stimulate the same pleasure centre in our brains as alcohol, marijuana, cocaine, or heroin. If stopping empty calories for few days causes flulike symptoms, tremor, restlessness or strong craving, you are likely addicted. This is the same problem drug addicts are facing. Stopping can be a challenge, needing strong resolve or slow guided withdrawal.

Mouth-watering "tasty" food directly appeal to our core survivalist brain and in the past— when death and disease from calorie starvation was the norm—this was acceptable. Today nutrition starvation is the norm, affecting two billion people globally. A deep and broad cultural shift is needed to steer the social behaviour towards healthier, joyful and productive directions. I am yet to meet a person who enjoys being diabetic, hypertensive, or having serious chronic health issues. Nutrition rich food should be the rich treats in social gatherings and parties, not nutrition poor treats full of empty calories filled with refined sugar, fat, and salt. We must work towards enhancing and extending a healthy productive life; from this we can benefit ourselves and it will also relieve unnecessary social and economic burdens on us—a charity to ourselves, our loved ones, and to the public.

Zakaria Khondker works in the biopharmaceutical industry in Boston area. He holds a PhD from the Gillings School of Global Public Health at University of North Carolina, Chapel Hill.