Overview of Micronutrients and Phytochemicals

Overview of Micronutrients and Phytochemicals

Introduction to Micronutrients

• Definition of Micronutrients: Essential nutrients needed in small amounts for proper body function. They include vitamins and minerals.
• Classification: Micronutrients can be classified into two main categories:
  • Vitamins: Organic compounds needed for various bodily functions.
  • Fat-soluble Vitamins: A, D, E, K - absorbed with dietary fat and stored in the body.
  • Water-soluble Vitamins: B-complex, C - widely distributed in body fluids, rarely stored in significant amounts.
  • Minerals: Inorganic elements vital to various bodily processes and can be categorized into:
  • Major Minerals: Required in larger amounts (greater than 100 mg/day) - e.g., calcium, sodium.
  • Trace Minerals: Required in smaller quantities (less than 100 mg/day) - e.g., iron, zinc.
  • Ultratrace Minerals: Extremely small amounts required and include elements like arsenic and boron.

Characteristics of Vitamins

• Essentials: Vitamins must be derived from the diet, cannot be synthesized by the body.
• Deficiency Symptoms: Absence of vitamins can lead to health problems, which are reversible with proper intake.
• Upper Levels and Megadoses: Toxicity can occur from excessive intake, particularly with fat-soluble vitamins due to accumulation in body fat.

Digestion, Absorption, and Storage

• Fat-soluble Vitamins: Absorbed alongside fats; impaired fat absorption (e.g., due to certain medications) can decrease absorption.
• Water-soluble Vitamins: Generally absorbed in the small intestine and can be excreted through urine, with some exceptions (B6 and B12).

Functional Roles of Micronutrients

• Vitamin Functions:
  • A: Vision, immune function
  • C: Antioxidant, collagen synthesis
  • D: Bone health, calcium metabolism
• Mineral Functions:
  • Calcium: Bone and teeth strength, nerve signaling
  • Iron: Oxygen transport throughout the body

Phytochemicals and Their Importance

• Definition: Naturally occurring compounds in plants, providing health benefits beyond basic nutrition.
• Categories:
  • Zoochemicals: Found in animal foods (e.g., omega-3s).
  • Phytochemicals: Found in plant foods, are responsible for a variety of colors and flavors, often linked to health benefits such as anti-inflammatory and antioxidant properties.
• Sources: Fruits, vegetables, whole grains, legumes, nuts, and seeds.

Health Benefits of Functional Foods

• Eating patterns rich in phytochemicals are associated with reduced risks of chronic diseases such as cancer and cardiovascular disease.
• Examples of Functional Foods: Blueberries (anticancer), garlic (antioxidant).

Dietary Supplements: Principles and Cautions

• Definition: Products taken to supplement the diet, including vitamins, minerals, herbs, amino acids, and probiotics.
• Risks: Supplements may not always be necessary; excessive intake can lead to toxicity.
• Recommendations: Whole foods are preferred sources for nutrients; supplements should not replace balanced meals unless advised by a healthcare professional.
• Who May Benefit from Supplements: Those on restrictive diets, pregnant women, older adults, individuals with certain health conditions.

Preservation of Vitamins and Minerals in Foods

• Best practices include:
  • Minimize cooking time and water usage.
  • Store fruits and vegetables properly (cool, dry places).
  • Avoid high-alkalinity cooking methods which can destroy specific vitamins.

Factors Influencing Nutrient Absorption

• Bioavailability: Factors affecting absorption include dietary components (fiber, other minerals) and health status (age, gender).
• Interactions: Excess intake of one nutrient can hinder absorption of another (e.g., high zinc can reduce copper absorption).

Conclusion

• Diet Composition: A balanced, varied diet rich in whole foods is key to meeting nutrient needs safely and effectively.
• Emphasizing nutrient-rich sources while being cautious of supplements helps maintain health and prevent deficiencies in the population.