growing tissue, and maintaining cellular function. [5][6][7] Despite its importance in health and human well-being, there are currently no tools that can monitor the nutrition content of foods. Current approaches to measure the nutrient content of food largely occur by bomb calorimetry [8,9] as well as fractionation with subsequent mass spectroscopy. [10][11][12] While these methods are accurate and effective, these require significant sample preparation and expensive/large machinery and are thus not suitable for measuring nutrient content direct from foods in on-the-fly settings so critical to many emerging applications.The major nutrients of food include carbohydrates (separated into complex carbohydrates and simple sugars), salts, oils or fats, protein, and finally water itself. These compose the majority of the weight of food, with carbohydrates composing 5-10%, fats or oils at 5-30%, salts at up to 1%, and proteins at up to 10% weight (with water composing the remaining mass and micronutrients at small concentrations). [13,14] Complex carbohydrates and proteins are difficult (if not impossible) to quantify direct from foods because these are not broken down significantly before intake. However, core nutrients such as simple sugars, salts, oils/fats, and water (that exist in molecules close to their metabolized forms) are key potential targets for nutrient sensing platforms. Indeed, the underconsumption/overconsumption of these critical nutrients are linked to a variety of markers of human health including mental state, [15,16] disease onset/maintenance, [17,18] and body development. [19,20] We recently proposed and demonstrated a partially selective biosensor composed of a silk fibroin biopolymer-interlayer interceding two electrodes (structured into a wireless format) for nutrient detection. [21] The silk biopolymer forms a dense, water-absorbent membrane that inherently performs sample preparation on the fluidic environment, while absorbing and/ or swelling in response to salts or simple carbohydrates. This device was attached to a human tooth and used to measure the sugar, salt, and alcohol content from a variety of oral liquids. This sensor had a variety of limitations including relatively slow response times, lack of programmability in sensor Nutrition measurement has broad applications in science, ranging from dietary assessment, to food monitoring, personalized health, and more. Despite its importance, there are currently no tools that offer continuous cotracking of nutrients direct from food. In this study, the multiscale engineering of silk biopolymer-interlayer sensors is reported for comonitoring of nutrients. By manipulating various nano-to mesostructural properties of such biosensors, sensors are obtained with programmable sensitivity and selectivity to salts, sugars, and oils/fats. Notably, this approach requires no specialized nanomaterials or delicate biomolecules. Programmable biosensors are further formatted for wireless readout and characteristics of these passive, wireless nutrient monito...