Food, Nutrients, and Metabolism: Understanding the Basics of Nutrition

Posted on Nov 15, 2024 in Biology

Food and Nutrients

What is Food?

Food is any substance or product that provides the elements necessary for:

  • Producing energy
  • Training, repairing, and maintaining the body and its functions

Food can be solid or liquid, natural or processed, plant-based or animal-based, and even genetically modified.

What are Nutrients?

Nutrients are organic and inorganic substances found in food that:

  • Provide energy for vital processes
  • Support growth and maintenance of organs and tissues

Functions of Nutrients

  1. Energy Function: Catabolism of nutrients releases energy for vital functions. Carbohydrates, lipids, and proteins primarily serve this function.
  2. Regulatory Function: Facilitates metabolic processes in the body. Vitamins and minerals play a key role in this function.
  3. Plastic Function: Responsible for renovating and building new tissues. Proteins are essential for this function.

Nutrition and Metabolism

Definitions

  • Feeding: Obtaining and preparing food for ingestion.
  • Diet: The total food consumed by a person over a period of time.
  • Nutrition: The processes involved in the body’s use of food, including ingestion, digestion, absorption, and elimination. It’s an involuntary and unconscious process.
  • Metabolism: The set of physicochemical processes occurring in a cell. It’s divided into two processes:
    • Catabolism: Reactions that release energy.
    • Anabolism: Reactions that use energy to build cell components.

Types of Feeding

  • Enteral Feeding: Providing food through a tube into the gastrointestinal tract.
  • Parenteral Feeding: Administering nutrients through the skin via a puncture.

Essential and Non-Essential Nutrients

  • Essential Nutrients: Nutrients the body cannot produce in sufficient quantities and must be obtained from food (e.g., vitamins, minerals, proteins, lipids, carbohydrates). Water is the most important essential nutrient, vital for life.
  • Non-Essential Nutrients: Nutrients the body can produce or synthesize from other nutrients (e.g., vitamin D).

Macronutrients and Micronutrients

Macronutrients

Nutrients found in larger proportions in the body, including carbohydrates, proteins, lipids, fiber, and water. Fiber and water are organic but do not provide energy.

Micronutrients

Nutrients found in smaller proportions in the body, including vitamins and minerals. They don’t provide energy but are essential for metabolic processes.

Trace Elements

Elements found in minute quantities in the body, such as selenium and magnesium.

Carbohydrates

Organic molecules composed of carbon, hydrogen, and oxygen. They are classified as simple or complex.

Simple Carbohydrates

  • Glucose: The most abundant monosaccharide in nature, used by every cell in the body, especially the nervous and renal systems.
  • Fructose: A monosaccharide found in fruits, honey, and some vegetables. It has a slow absorption rate.
  • Sucrose: A disaccharide found in table sugar, formed from two glucose molecules.
  • Lactose: A disaccharide found in the milk of mammals.

Complex Carbohydrates

  • Starch: The principal plant carbohydrate, a polysaccharide that serves as a reserve carbohydrate in cereals, tubers, and legumes.
  • Glycogen: The most abundant polysaccharide in animal cells, composed of glucose molecules. It’s found in the liver and skeletal muscle.
  • Cellulose: Found in the cell walls of plants. The human body cannot digest it.
  • Pectins: Polysaccharides found in plant cell walls, not absorbed by humans.

Blood Glucose Regulation

Regulated by the opposing actions of insulin and glucagon. These hormones maintain normal blood glucose levels. Glucagon helps release glucose from glycogen when blood sugar is low, while insulin helps glucose enter cells.

Cholesterol

Function

s for nutrients that are vitales.Los q. see this fun.son: HC, lipid
and proteinas.FUNCION REGULATORY: is to facilitate metabolic processes taking place in the vitamins and organismo.son PLASTIC minerales.FUNCION: is responsible for renovating and building new tissues. are proteinas.ALIMENTACION: defined as how to obtain andprepare food for later ingestion.DIETA: whole foods that each person consumes in a fraction of tiempoNUTRICION the set of processes that suffer food into the body from its ingestion, digestion, absorption and eliminacion.proceso involuntary and inconsciente.METABOLISMO: is the set of reactions and physicochemical processes that occur in a cell. sivide in 2 processes are CATABILISMO: these reaccciones release energia.ANABOLISMO: reactions using the energy released to form the components of
the celulas.ALIMENTACION ENTERAL: the contribution of food through a tube into the tract gastrointestinalALIMENTACION PARENTERAL: the route of administration is done through one or more layers of the skin by an ESCENCIALES puncion.NUTRIENTE are those that the body does not is able to manufacture for itself in sufficient quantities and therefore must be supplied in alimentacion.Ej. the vita., miner.protei., lip, hc.el most important principles is water ESCENCIALES without serious imporsible the vida.NO ESCENCIALES: Are those the agency is able to produce or manufactured from other nutrients eg . the vit.D

Macronutrients: nutrients found in greater proportion as hydrates C., proteinuria, lipi .. fiber and water are macronutrients but not energy aportana but organicos.MICRONUTRIENTE involved in multiple processes: they are what are found in small proportions in the body are the vitm.y mine. they do not provide energy but they are an indispensable metabolicos.OLIGOELEMENTO processes: They are found in minute cantidadesen the body such as selenium, magnesium.
Carbohydrates: are carbohi.gluci. po azucares.compuestos organic molecules or carbon hidro.y oxigeno.Se clasisfican in simple and compound.
SIMPLE: AZU.PRIN. Glucose: monosac.el most abundant type of nature used po every cell in the org.el siste.nerv.y the renal.solo utili.estas this glucosa.Fructosa: type: Monosaccharide = fruits and honey fewer vegetables . its rate of absorption is lenta.Sacarosa: type: = disaccharides present in table sugar formed from 2 molecules glucosa.Lactosa: type: = the disaccharide sugar of milk mamiferos.COMPLEJOS.Starch .– AZU.PRINC plant: type: polysaccharide = reserve carbohydrates cere.tuber.pta vegetables and legumes rich in animal glycogen .–: type: polysaccharide: is the most abundant in animal cells, composed of molecules of glucosa.abund.en liver and skeletal muscle and hemicelulosa.tipo polysaccharide .– Cellulose: is in the cell walls of all vegetables. not the human body absorbs it .– abs.los herbivory Peptinas: type: polysaccharide: in the ground cover is not being absorbed humano.REGULACION BLOOD GLUCOSE: Performed by the action of the 2 hormone systems opposing the insulin and glucagon, the actions of both serves to maintain normal glucose levels in sangre.El glucagon glycogen helps move glucose and insulin levels low blood sugar because that helps the glucose enter in celulas.FUNCION CHOLESTEROL: It is a basic component of cell menbrana and serves as a precursor for the synthesis of bile acids, hormones sexuality. hor.suprarenales.Su and excess, is related to cardiovascular patolgias through the formation of plaques ateromas.COMOCIRCULATION CHOLESTEROL IN THE BLOOD: circulates freely in plasma sanguineo.existen 3 types: high density lipoprotein HDL. HDL-cholesterol is deposited in the atherosclerotic plaque prevents ischemic .– LDL or low density lipoprotein can be deposited in atherosclerotic plaques and therefore involved in VLDL .– cardiovascular pathologies: lipoprotein : very low density similar to LDL in its operation.