Vitamins and Minerals Notes

Vitamins

• General requirement to know all vitamins covered.
• Water-soluble vitamins:
  • Vitamin B1 (Thiamine)
  • Vitamin B2
  • Vitamin B3
  • Vitamin B5
  • Vitamin B6
  • Vitamin B12
  • Biotin
  • Folate
  • Vitamin C
• Fat-soluble vitamins:
  • Vitamins A, D, E, and K
• Key information to know for each vitamin:
  • Other names
  • Forms
  • Functions
  • Roles
  • Deficiency symptoms
  • Toxicity outcomes
  • Food sources

Water-Soluble vs. Fat-Soluble Vitamins

• Key differences to identify:
  • Absorption
  • Transport
  • Storage
  • Excretion
  • Toxicity
  • Requirements
• Fat-Soluble Vitamins:
  • Require bile for absorption.
  • Travel via the lymphatic system (hydrophobic).
  • Excesses stored in the liver.
  • Can go without them for weeks or months.
  • Higher risk of toxicity.
  • Not readily eliminated through the kidneys.
  • Need chylomicrons to act as carriers.
• Water-Soluble Vitamins:
  • Absorbed directly into the bloodstream.
  • Travel freely.
  • Readily excretable.
  • Needed more frequently.
  • Lower risk of toxicity overall, but toxicity is still possible.

Bioavailability

• Definition: The actual amount of a nutrient that is absorbed and used by the body.
• Depends on:
  • Quantity provided by the food.
  • Amount absorbed and used by the body.
• Example: Consume 100mg of a vitamin, but only absorb 20mg.
• Factors affecting bioavailability:
  • Efficiency of digestion and transit time.
  • Previous nutrient intake and nutritional status:
    • Example: Iron deficiency anemia leads to higher iron absorption when supplemented.
    • Vitamin C increases iron absorption from non-heme iron food sources.
  • Method of food preparation:
    • Raw vs. processed.
    • Storage methods (airtight containers).
    • Cooking methods (minimal water, microwave, steamer).
    • Reusing cooking water in dishes like casseroles and soups.
  • Source of the nutrient:
    • Synthetic vs. fortified.
    • Supplemental folate is more easily absorbed than folate from food sources.
• B group vitamins and vitamin C: Absorb directly into the blood and travel freely.
• Fat soluble vitamins (vitamins A, D, E, and K): absorbed first into the lymph and then the blood.

Major and Trace Minerals

• Major Minerals (covered):
  • Calcium
  • Sodium
• Trace Minerals (covered):
  • Iron
  • Zinc
  • Iodine
• Key information to understand:
  • Bioavailability
  • Enhancers and inhibitors
  • Roles and functions
  • Deficiency symptoms
  • Toxicity outcomes
  • Food sources
• Examples:
  • Iron absorption enhanced by vitamin C.
  • Calcium found in dairy foods, important for bone structure.
  • High calcium intake can impede iron absorption due to competition for absorption, especially in children who drink excessive amounts of milk.
  • Ca^{2+}
  • Fe^{2+}

Supplements

• Preferred sources of vitamins and minerals are food sources.
• Role for supplements in certain cases.
• Who might need supplements:
  • People with nutritional deficiencies.
  • Those with low energy intake (fasting, avoiding food groups).
    • Vegans and those with atrophic gastritis need vitamin B12.
    • Lactose intolerant individuals, those with milk allergies, or inadequate dairy intake might be deficient in calcium.
  • Certain life stages:
    • Infancy
    • Pregnancy
    • Lactation
    • Elderly
  • Disease, infections, injuries, or surgery impacting nutrient absorption, digestion, or metabolism.
  • Medications that interfere with nutrient use or metabolism.
• More supplements doesn't always mean better; effectiveness plateaus and can lead to toxicity.
• Some groups benefit from supplements.

Putting it All Together

• Relate nutrients, macros, and microbes to food groups and sources.
• Integrate knowledge of vitamins, minerals, and nutrients with overall recommendations.
• Australian Guide to Healthy Eating:
  • Plate designed to meet RDIs if approximate portions are consumed daily.
  • Ensures adequate energy and fat soluble vitamins.
  • Water is important; shown alongside the plate.
    • Necessary, especially with a high-fiber diet, to facilitate food passage through the gut.
  • Extras:
    • Occasional/discretionary foods (sometimes foods in small amounts).
    • Oils (polyunsaturated or monounsaturated fats and fat soluble vitamins) to be consumed in small amounts.
  • In Australia, a third of energy intake comes from discretionary/nutrient-poor foods high in sugar and saturated fat.
  • Consume less discretionary food and more core food groups with key nutrients.

Feedback

• UTI feedbacks at the end of the semester appreciated.
• Feedback regarding:
  • What was done well.
  • What was not done so well.
  • Areas for improvement.
  • Meeting expectations.
  • Other improvements to suggest.