Final answer:
Water soluble vitamins are the most susceptible to loss in foods as they can easily be lost during food processing, cooking, or storage, unlike fat soluble vitamins which are more stable and can accumulate in the body's lipid stores.
Step-by-step explanation:
The nutrient most susceptible to loss in foods is water soluble vitamins. These vitamins, including the B-complex vitamins and vitamin C, can be directly absorbed into the bloodstream from the intestine but are also easily lost during food processing, cooking, or storage. In contrast, fat soluble vitamins, such as vitamins A, D, E, and K, are absorbed with dietary lipids and can accumulate in the body's lipid stores, making them less susceptible to loss compared to water soluble vitamins. Carbohydrates, lipids, and proteins are considered macronutrients and are generally more stable during food preparation. Moreover, some vitamins can be synthesized by the body, such as vitamin A from ß-carotene in orange vegetables, or vitamin D through skin exposure to sunlight.