Environmental and Lifestyle Factors Affecting Human Health

Posted on Dec 6, 2024 in Medicine & Health

How Does the Environment Influence Health?

Harmonious development allows a person to thrive in a healthy environment. Pollution negatively impacts health, as do societal and family factors, which influence both physical and mental well-being.

Determinants of Health

  • Lifestyle: Diet, obesity, alcohol consumption.
  • Environmental: Pollution.
  • Biological: Diseases, obesity.

Modifiable Health Determinants

Environmental factors, lifestyle choices, healthcare systems, and some biological factors (excluding hereditary ones) can be modified by human activity.

Cardiovascular Disease Risk Factors

Risk factors include: Hypertension (high blood pressure), obesity, alcohol consumption, tobacco use, excessive exercise, sedentary lifestyle, sugary drink ingestion, and diets high in protein.

Transmissible vs. Non-Transmissible Diseases

Transmissible: Flu, chickenpox, meningitis, pneumonia.

Non-Transmissible: Cerebral palsy, diabetes, epilepsy.

AIDS Mortality in Poor Countries

Higher AIDS mortality in poor countries is due to factors like lack of access to condoms, poor nutrition, inadequate hygiene, and limited medical care.

High Cholesterol and Cardiovascular Risk

High cholesterol leads to atheromatous plaques. Inflammation can cause plaque rupture, hindering blood circulation and promoting thrombus formation. Severe cases can lead to artery blockage due to atheroma growth.

Mechanisms of Cardiovascular Disease from Tobacco Use

Tobacco smoke acutely increases arterial pressure and heart rate by stimulating nerve endings and increasing sympathetic nervous system catecholamines (epinephrine and norepinephrine). Both treated and untreated normotensive smokers have higher blood pressure than non-smokers.

Relationship Between Diabetes and Obesity (Fig 5.2a)

There is a correlation; obesity increases the risk of developing diabetes.

Malaria

Malaria is prevalent in warm, humid, swampy areas, often in tropical regions with lower health standards.

Prevention includes: Avoiding mosquito bites, draining wet areas, using mosquito nets, insecticides, and repellents.

Malaria Treatment Challenges

1. Malaria disproportionately affects developing countries with limited research and investment.
2. Protozoa (eukaryotes) are phylogenetically closer to humans than bacteria, making it challenging to develop treatments that target the protozoa without harming humans.

AIDS

a) Nucleic acid: RNA

b) Cell entry and attack mechanism:

  1. HIV binds to the cell membrane via receptors.
  2. Viral protein enters the host cell.
  3. The capsid degrades, releasing RNA.
  4. Viral reverse transcriptase synthesizes viral DNA from RNA.
  5. Proviral DNA degrades the nucleus and integrates into the host cell’s chromosome.
  6. Once activated, proviral DNA transcribes viral RNA, which moves to the cytoplasm.
  7. Viral RNA directs the formation of new viruses.
  8. New viruses leave the host cell by budding.

Elements Necessary for Infectious Disease

  1. Existence of an infectious source: Germs can live in various reservoirs, including humans, animals, land, and water.
  2. Propagation of infectious agents: Transmission from source to host can be exogenous (direct or indirect) or autogenous.
    • Direct: Germs reach the skin or mucous membranes through contact (e.g., sexually transmitted infections).
    • Indirect: Transmission via air, water, food, inanimate objects, or animals.
    • Autogenous: Infections caused by microorganisms that normally live as saprophytes in humans but become pathogenic.
  3. Penetration of microorganisms: Germs enter the body through various entry points (skin, respiratory tract, digestive tract, oropharynx, etc.).

Key Health Terms

Symptom: Subjective manifestation of disease (e.g., pain). If objective, like fever, it’s called a sign.

Sign: Any objective manifestation of disease or health alteration.

Antibiotic: A substance produced by a living organism or a synthetic derivative that, in low concentrations, kills or inhibits the growth of susceptible microorganisms. Used in human and animal medicine and horticulture to treat infections.

Antiviral: A drug used to treat viral infections.

Vaccine: A preparation containing dead or inactivated pathogenic microorganisms to stimulate antibody production and provide immunity against disease.

Cancer

Cancer: A group of diseases characterized by uncontrolled growth and division of malignant cells (carcinogens).

Apoptosis: Programmed cell death.

Metastatic: The spread of cancer cells to different organs from the initial tumor.

Radiotherapy: Treatment using ionizing radiation (X-rays, radioactivity, gamma rays, alpha particles).

Chemotherapy: Treatment using chemical substances (drugs) to cure diseases like tuberculosis, autoimmune diseases, and cancer.

Balanced Diet

A balanced diet provides adequate nutrients (carbohydrates, fats, proteins, vitamins, minerals, and trace elements) and maintains a healthy body weight for height. Overweight and obesity are risk factors for disease. A balanced diet should be rich in fruits and vegetables, with fish preferred over red meat, and a reduction in saturated fat consumption. Calorie distribution throughout the day should be approximately 20-25% for breakfast, 35-40% for lunch, 15-20% for a snack, and the remainder for dinner. The Mediterranean diet is considered a healthy dietary model.