Nutrition, Food Safety, and Respiratory Health Essentials

Understanding Diet and Nutrition

What is Diet?

Diet: The amount and type of food we consume.

Types of Diets

Balanced Diet: A healthy diet provides the body with the right amount of energy and different types of nutrients.

Mediterranean Diet: This is a balanced diet that combines all foods properly.

Genetically Modified Organisms

GMO Foods: These are produced from organisms that have had genetic material from another living being introduced.

Food Preservation and Additives

Food Preservation Methods

Food can be preserved using chemical and physical methods:

• Heating foods to high temperatures for a few seconds can eliminate a number of bacteria.
• Preservation by cold (refrigeration/freezing).
• Freeze-drying eliminates water from food.
• Chemical preservation uses preservatives or acidic substances.

Food Additives

Food Additives: These are substances added to foods and food preparations to maintain their properties, recover lost qualities, and prevent decomposition.

Categories of Additives:

• Acidifiers: Used to acidify food and prevent the development of microorganisms.
• Antioxidants: Prevent fats from oxidizing.
• Emulsifiers: Used to disperse one substance within another.
• Colorants: Add color.
• Preservatives: Prevent the development of microorganisms.

Food Safety and Contamination

Types of Food Contamination

• Food Contamination by Bacteria: When ingested, these can produce food infections, causing symptoms like diarrhea and fever.
• Food Contamination by Toxins: Ingesting these foods causes food poisoning.
• Food Contamination by Chemicals: This is typically accidental contamination.

Cross-Contamination

Cross-Contamination: Occurs when microorganisms are transferred from contaminated food to food that is not contaminated.

Nutrition-Related Health Issues

Malnutrition: This is inadequate nutrition, due either to poor food intake or excessive consumption of food.

Consequences of Poor Diet

• Deficiency Diseases: Such as vitamin deficiency or anorexia, appear as consequences of a poor diet.
• Obesity: Emerges, generated by an excess in food consumption.
• Anorexia: Consists of malnutrition and severe weight loss (emaciation).
• Bulimia: Characterized by a loss of control over food intake, often involving binge eating followed by purging.

The Respiratory System

Parts of the Respiratory Tract

• The Nose: Contains two cavities open to the outside and covered by nasal mucosa.
• The Pharynx: A common conduit for both the airway and the digestive tube. It contains the epiglottis.
• The Larynx
• The Trachea
• The Bronchial Tree

Lung Ventilation (Breathing)

Lung Ventilation: The circulation of air into and out of the lungs.

There are two movements:

• Inspiration (Inhalation)
• Expiration (Exhalation)

Gas Exchange

Gas Exchange: This is a process that occurs via diffusion through the thin, moist membranes of the alveoli. Oxygen is more concentrated in the air within the alveoli, and it tends to diffuse into the blood.

Mechanics of Breathing

Inspiration: An active process. The ribs are raised by the contraction of the intercostal muscles and scalene muscles. The diaphragm lowers to increase the volume of the ribcage. The lungs are pulled along with the ribs, which increases their volume and decreases the pressure inside, causing air to enter.

Expiration: A generally passive process. Air exits the lungs because they are compressed by the ribs, which in turn are driven by the diaphragm as it rises.