Intersections of Nutrition: Retracing Yesterday, Redefining Tomorrow

The last several decades have seen a major shift in how diet is viewed: from a purely nutritional function to a platform to mitigate and safe- guard against chronic diseases. A healthy diet defined by the WHO as one that helps to protect against malnutrition in all its forms (undernutri- tion, overnutrition, or micronutrient deficiency), and noncommunicable diseases (NCDs) like diabetes, heart disease, stroke, and cancer, has now become the ultimate goal

The early development of taste and food pleasure plays an impor- tant role in children and has long-lasting influences on subsequent food preferences and choices. Eating a variety of foods is essential to achieve adequate coverage of macro- and micronutrients. However, children’s vegetable consumption often falls below current recommendations, high- lighting the need to identify strategies that promote better acceptance of vegetables.

Apart from our innate liking for sweet foods and disliking for very bitter foods, sensory pleasure for foods is mostly acquired through our early eating experiences. Infants have a fine palate and more taste buds than adults when they are born. They have about 10,000 taste buds all around their tongues including at the roof of their mouths and the back and sides of the mouth. The flavors of what a mother eats while being pregnant can reach the fetus and help set up flavor preferences later on. From birth, infants can taste and smell foods, an experience that can take place through human milk as the food eaten by the mother influences the flavor of her milk, and thereby the child’s preference.

The term “triple burden of malnutrition” refers to the coexistence of undernutrition (stunting and wasting), micronutrient deficiencies (often termed hidden hunger), and overnutrition (overweight and obesity). Globally, there is a strong inverse association between a country’s wealth measured as gross domestic product (GDP) and undernutrition and levels of micronutrient deficiencies. As countries pass through the economic transition and gain in wealth, it is gratifying to see that rates of undernutrition decline rapidly. But conversely, rates of overnutrition seem to inexorably grow with increasing wealth, an “overcorrection” that has not yet been successfully avoided by any emerging nation.

Malnutrition affecting appropriate growth and development in chil- dren can take the form of undernutrition, overnutrition, or both com- bined (excess energy and inadequate micronutrient intake). Malnutrition in early life is known to increase susceptibility to infectious illness and even the risk of death in young children. It also contributes to neurodevel- opment delays in later school and social performance, and increased risk of adult metabolic diseases. The long-term effect of these early exposures and challenges is stipulated by the phenomena described in the devel- opmental origins of diseases, where environmental exposures, such as nutrition, can induce specific developmental programming or metabolic programming, a set of cellular or systemic physiological adaptations with possible persistent negative health effects in adulthood. When describ- ing early growth, the role of metabolism and metabolic programming is essential to understand the impact of nutrition, and the relevant adapta- tions being built during infancy. The available body of literature explains how specific dietary components, like breastfeeding or protein intake, can influence growth and body composition trajectories. Studies have consis- tently shown that although formula-fed infants grow well in line with the World Health Organization growth standards, differences in their growth dynamics and body composition distribution do exist. Some of these may explain the moderate protection that breastfeeding confers against future metabolic disease risk.

Human milk provides all necessary nutrients and molecules to give infants the best possible start in life. Human milk consists of both key nutritional factors and a myriad of bioactives. Of which the concentrations are influenced by several factors like maternal genetics, time of lactation, the environment, maternal lifestyle, and more. Human milk oligosaccharides (HMOs) are one of the bioactive compounds that have been extensively investigated due to their impact on the development of an infant’s microbiome, immune system, and general health.

Human milk is the best source of infant nutrition and is recognized as a biological fluid vital for optimal growth and development of the infant. Exclusive breastfeeding during the first 6 months of infant life not only provides optimal nutrition but also significant short- and long-term benefits to infant and mother [1]. Sapiens’ milk has coevolved with mammalian species for millions of years which has resulted in this remarkable secretory product of nutrient-rich milk [2].

The first few years of life are key to infant development and the estab- lishment of long-term health. During this critical period of metabolic, immune, and cognitive development, the microbial ecosystem residing in the gut (called the gut microbiota) is also observed to undergo profound changes. This process, characterized by a gradual diversification of the ecosystem and the successive establishment of bacterial taxa, has been linked with health outcomes [1]. Hence, the need to accurately capture the optimal maturation process of the gut microbiota in infancy. One way to do so is using a gut microbiota maturation trajectory. This is defined by applying machine learning approaches to healthy infants’ microbiome data, generating a growth-like curve. The method has proven useful in identifying risk factors that can induce deviation of infants’ microbiota from the reference trajectory as well as nutritional interventions that may help to revert back these changes [2]. Yet, improvement to the method to better define a healthy refence curve together that can be used universally is still required. Second, a better-defined reference will help to identify elements of the gut microbiota (such as taxa of functions) that are key to the development process to be able to use them as target when designing interventions that support optimal maturation.

Nutrigenomics, a field that has received increased attention over the past decade, investigates how genetic traits of an individual interact with their diet and helps determine which food component is beneficial to the individual’s health. This provides an understanding on how nutrition affects the balance between improving and/or restoring health and determining the risk of developing chronic diseases during an individual’s lifetime. It addresses how diet influences gene transcription, protein expression, and metabolism and views food as capable of reversing disease and stalling aging. The development of “personalized diets,” identification of molecular biomarkers or new bioactive food ingredients, and the validation of the effectiveness of these bioactive ingredients as functional food components are the foundations of this field.