“You are what you eat.” It means our diet determines our health. The food we eat is a basic and fundamental ingredient of our lives. Through the digestive process, food is broken down into smaller pieces and absorbed to support our daily functioning.
With the rising consciousness of a healthy lifestyle, we now know that other than eating to fill ourselves up, we also need to eat well to optimize our body operations and prevent chronic illnesses. However, what does ‘eat well’ means? Here, we refer to obtaining adequate and diverse nutrients our body needs, apart from macronutrients such as carbohydrates, proteins or fats, micronutrients such as minerals, vitamins and antioxidants are equally essential. So, can we get all essential nutrients from the plate?
The Declining Nutrient Content in Food
Increasing evidence has been showing that the mainstream industrial food system is not serving us well when it comes to the nutrient value of food. (Read more to know why our food nutrient content is decreasing.) A landmark study from the University of Texas (UT) found that there are “reliable declines” in the amount of proteins, calcium, vitamin B2 and vitamin C in vegetables and fruits over the past half century. If our diets lack the necessary balance of nutrients, unbalanced nutrients in our diets will lead to biological dysfunction and diseases, e.g. heart disease, stroke and type II diabetes.
Among the micronutrients mentioned, polyphenols have been one of the trending nutrients in recent years. Polyphenols are naturally synthesized in plants as immune. For us, consuming polyphenols can prevent cell aging by neutralizing oxidation. Therefore, polyphenols can act as antioxidants and reduce inflammation, which is thought to be the root cause of many chronic illnesses. Common types of polyphenols include flavonoids in brightly colored vegetables, curcumin in turmeric and lignans in flax seeds, sesame seeds and whole grains. The amount and type of polyphenols in foods depend on the food species, its origin, ripeness and how it was farmed, transported, stored and prepared. Thus, the polyphenol content of each vegetable and fruit in the market can be different.
With variance in nutrient content in vegetables and fruits, how do we, as consumers, differentiate our purchases according to their nutritional values? If I want to buy blueberries which are known to contain beneficial nutrients like anthocyanins (a type of polyphenols), potassium and vitamin C. However, there are thousands of blueberries in the market. How can I choose the blueberries with higher polyphenol content when they all look the same? Is there a convenient and instant method to help us understand better what vegetables and fruits are nutrient-dense or healthy?
This is how our project starts.
 Davis, D. R., Epp, M. D., & Riordan, H. D. (2004). Changes in USDA Food Composition Data for 43 Garden Crops, 1950 to 1999. Journal of the American College of Nutrition, 23(6), 669–682. https://doi.org/10.1080/07315724.2004.10719409
 Chadwick, R. (2004). Nutrigenomics, individualism and public health. Proceedings of the Nutrition Society, 63(1), 161-6.
 Hunter, P. (2012). The inflammation theory of disease. The growing realization that chronic inflammation is crucial in many diseases opens new avenues for treatment. EMBO reports, 13(11), 968–970. https://doi.org/10.1038/embor.2012.142
 Petre, A. (2019, July 8). What Are Polyphenols? Types, Benefits, and Food Sources. Retrieved from https://www.healthline.com/nutrition/polyphenols