Nutrition and Dietary Patterns

Healthier dietary patterns include Mediterranean, Japanese, and Nordic diets, which have been associated with better overall health outcomes. These diets are characterized by a higher consumption of whole, unprocessed foods and a variety of plant-based ingredients. This diversity in food choices promotes a rich intake of essential nutrients.

Features of Traditional Diets

• Emphasis on a wide range of food groups:

  • Fruits: Rich in vitamins, minerals, and antioxidants that support overall health. They help in reducing the risk of chronic diseases and boosting the immune system.

  • Vegetables: Crucial for gut health and provide fiber that aids digestion and promotes satiety, as well as contributing to lowering cholesterol and blood pressure.

  • Legumes: Excellent source of protein, fiber, and various micronutrients, contributing to lower cholesterol levels, improved heart health, and stable blood sugar levels, making them a staple in many diets.

  • Whole grains: Such as oats, barley, and brown rice, which offer fiber and vital micronutrients while assisting in blood sugar regulation and reducing the risk of diabetes.

• These diets also include healthy fats that are vital for cardiovascular health:

  • Olive oil: A staple in the Mediterranean diet, known for its beneficial monounsaturated fats and anti-inflammatory properties. It has been associated with reduced risk of heart disease and improved longevity.

  • Fish oil: Rich in omega-3 fatty acids, which are essential for brain development and function, may help reduce the risk of chronic diseases and are beneficial for mental health.

• A hallmark of traditional diets is the minimal consumption of processed foods, which often contain unhealthy additives and preservatives that can lead to various health issues, including obesity and metabolic syndrome.

• These diets are typically linked with regular physical activity and communal eating practices, enhancing social interaction and psychological well-being. Eating together can foster a sense of community, which has been shown to positively affect mental health.

Commonalities and Differences

• Common Features:

  • A strong focus on plant-based foods provides essential nutrients, supports sustainable agriculture, and encourages biodiversity.

  • Low consumption of processed foods, which helps in reducing the risk of chronic diseases, including diabetes and hypertension.

  • Moderate intake of meat, with an emphasis on lean sources and seafood, often linked to better health outcomes due to lower saturated fat intake.

• Differences:

  • Staple foods vary; for instance, rice is a staple in many Asian diets, while pasta is essential in Mediterranean diets, which influences the overall dietary composition.

  • Different regions utilize various fat sources in their preparations; for example, Asian cuisines may favor sesame oil or coconut oil, whereas Nordic diets might use butter or fish oils for cooking.

Health Benefits of Traditional Diets

• Traditional diets have been linked to lower rates of chronic diseases such as heart disease, diabetes, and obesity, owing to their nutrient-dense compositions characterized by a rich variety of vitamins, minerals, and phytonutrients.

• These dietary patterns typically exhibit low levels of harmful additives and possess high antioxidant and fiber contents, contributing to longer life expectancy and better quality of life. Nutritional components such as polyphenols and fiber also play a significant role in maintaining gut health and preventing inflammation.

• Regular adherence to these diets has also been shown to support mental health and cognitive function, likely aided by the types and proportions of fats, omega-3 fatty acids, and micronutrients consumed, which are known to enhance neuroplasticity and emotional well-being.

Carbohydrates

Recommended Intake

• Sedentary individuals: 3-5 g/kg body weight/day, which is sufficient to maintain energy levels without causing fat accumulation.

• Endurance athletes: 6-10 g/kg body weight/day is necessary to replenish glycogen stores after prolonged physical exertion for optimal performance and recovery.

Types of Carbohydrates

• Simple sugars:

  • Glucose, fructose, sucrose (found in fruits and table sugar) are easily digestible and provide quick energy but can lead to spikes in blood sugar levels when consumed excessively.

• Complex carbohydrates:

  • Starch and fiber are digested slowly, providing sustained energy and promoting digestive health. Fiber is especially important for regular bowel movements and can aid in cholesterol management and blood sugar control.

Effects on Health

• Simple carbohydrates can spike blood sugar and insulin, leading to potential energy crashes and increased cravings.

• Complex carbohydrates are digested more slowly, regulating energy release and appetite, contributing to improved satiety and long-term weight management.

Energy Storage

• In blood: Glucose is used immediately for energy demands and can quickly elevate energy levels during physical activity.

• Stored as glycogen in the liver and muscles, which acts as a readily available energy source during times of increased demand such as exercise.

Blood Sugar Control

• Essential to prevent spikes and crashes in energy, which can lead to fatigue and irritability.

• Regulating blood sugar levels reduces the risk of insulin resistance, diabetes, and metabolic disorders, critical in avoiding long-term health complications.

Fats

Types of Fatty Acids

• Saturated fats: Typically found in animal products; should be consumed in moderation due to their association with increased cholesterol levels.

• Unsaturated fats (mono- and polyunsaturated): Present in plant oils, nuts, seeds, and fish; known for their heart health benefits, including lowering bad cholesterol and reducing inflammation.

• Trans fats: Artificially created through hydrogenation; should be avoided as they have been directly linked to increased heart disease risk.

Common Fat in Food and Body

• Triglycerides are the most common form of fat found in foods and the body, serving as a major energy source; elevated levels can indicate metabolic issues.

Cholesterol

• A waxy substance essential for cell membranes and hormone production.

• Made in the liver and found in animal foods; monitoring dietary cholesterol intake is important for managing cardiovascular health.

Healthy Fat Recommendations

• Eat more: Unsaturated fats from sources like nuts, seeds, fatty fish, and olive oil should be prioritized in a balanced diet for their health benefits.

• Eat less: Saturated fats should be limited, and trans fats should be avoided altogether to minimize cardiovascular risks.

Protein

Recommended Intake

• Sedentary individuals: 0.8 g/kg body weight/day is sufficient to meet basic bodily functions, including tissue repair and enzyme activity.

• Athletes: Protein needs can increase to up to 2.0 g/kg/day depending on the type and intensity of the sport, aiding in muscle recovery and growth.

Composition of Proteins

• Made of amino acids:

  • Essential: Must be obtained from the diet, crucial for synthesizing proteins required for various physiological functions.

  • Non-essential: Can be synthesized by the body and do not need to be consumed through food.

Functions of Protein

• Building tissue and muscles, critical for growth and maintenance of bodily structures.

• Forming enzymes and hormones that regulate metabolic processes.

• Supporting immune function by producing antibodies and other immune cells.

• Providing energy when carbohydrates or fats are unavailable, serving as a secondary energy source.

Protein Storage

• Unlike fats and carbohydrates, protein is not stored in the body in significant amounts; excess protein is converted to fat or used for energy, emphasizing the importance of balanced protein consumption.

Dietary Assessment

Definition

• Assessment of dietary intake to understand nutritional habits and their impacts on health, crucial for informing dietary guidelines and personal nutrition strategies.

Methods

• Food diaries are useful for recording daily intake and patterns over time.

• 24-hour recall involves asking individuals to report all food and drinks consumed in the past day, providing a snapshot of dietary habits.

• Food frequency questionnaires help in understanding habitual intake of various food groups over time, identifying nutrient gaps or excesses.

Assessment Purpose

• Compare intake against dietary guidelines to ensure nutritional adequacy.

• Identify nutritional deficiencies that may lead to health issues and inform health advice tailored to individual needs.

• Guide diet planning for individuals or populations, aiming to promote better health outcomes and reduce disease risk.

Vitamins and Minerals

Toxicity

• Excess intake of some vitamins, particularly fat-soluble ones (A, D, E, K), can lead to toxicity, underscoring the importance of balanced consumption.

Types of Vitamins

• Fat-soluble: A, D, E, K, which are stored in the body and can accumulate to toxic levels if consumed excessively.

• Water-soluble: B-complex and C, which are not stored and need to be consumed regularly to prevent deficiencies.

Health Issues from Deficiencies

• Vitamin D: Insufficient levels can lead to rickets in children and osteomalacia in adults, affecting bone health.

• Vitamin C: Deficiency may lead to scurvy, characterized by fatigue, gum disease, and skin issues.

• Vitamin B12: Leading to anemia and potentially neurological issues if not adequately consumed, particularly in vegetarians and vegans.

• Vitamin A: Deficiency can cause night blindness and increase susceptibility to infections.

Minerals of Concern in NZ

• Iron deficiency is particularly prevalent among women due to menstruation and dietary patterns, warranting monitoring and potential supplementation.

Factors Affecting Availability

• Phytates, oxalates, and tannins found in certain foods can inhibit mineral absorption.

• Poor gut health, including conditions like leaky gut, can impair nutrient uptake.

• Processing and cooking methods can alter the bioavailability of vitamins and minerals, highlighting the need for mindful preparation techniques.

Energy Balance

Equation

• Energy in (food) = energy out (basal metabolism + activity + thermogenesis) represents the balance necessary for maintaining body weight.

Energy Expenditure

• Basal Metabolic Rate (BMR) represents the energy expended at rest for vital functions like breathing, circulation, and cellular activities.

• Physical activity contributes to overall energy expenditure and varies significantly based on activity level and intensity.

• Thermic effect of food refers to the energy required for digestion and metabolism of nutrients, which accounts for a small percentage of daily energy expenditure.

Weight Gain Scenario

• If energy consumed exceeds energy expended, the excess is stored as body fat, leading to weight gain over time.

Fat Cell Dynamics

• Initially, fat cells enlarge to store excess energy; prolonged energy excess can lead to an increase in the number of fat cells (adipocytes), complicating weight management.

Alcohol

Nutritional Status

• Alcohol, while not a nutrient, provides energy (7 kcal/g) but does not contribute any vitamins or minerals, making it an empty calorie source.

• Chronic alcohol consumption can hinder nutrient absorption, leading to deficiencies over time, especially in B vitamins and minerals.

Long-term Consequences

• Chronic alcohol use is associated with liver disease, cancer, cardiovascular diseases, and mental health issues such as depression and anxiety, emphasizing the need for moderation.

Energy and Exercise

Energy Sources

• The body primarily utilizes glucose from carbohydrates and fatty acids from fats for energy during various intensities of exercise.

• Protein can also serve as an energy source if carbohydrate stores are depleted, particularly during prolonged exercise.

Energy Currency

• ATP (adenosine triphosphate) is the primary energy currency in cells, providing immediate energy for cellular processes and muscle contractions during physical activity.

Energy Storage Locations

• Glycogen is stored in muscles and liver, serving as a quick energy source during high-intensity activities.

• Fat is stored in adipose tissue and serves as a long-term energy reservoir, crucial during lower intensity or prolonged exercise.

Maximizing Glycogen Storage

• Important for improved endurance and recovery, achieving optimal glycogen levels can enhance athletic performance.

Nutrition for Exercise

• Before Exercise: Consuming a meal rich in carbohydrates and protein (e.g., banana with peanut butter) helps fuel activity and maintain energy levels.

• During Exercise: Quick-acting carbs (e.g., sports drinks or gels) are effective for sustained energy during prolonged periods of activity.

• After Exercise: A combination of carbs and protein (e.g., chocolate milk with a sandwich) aids in glycogen replenishment and muscle repair.

Supplements

• Supplements can be beneficial but are generally not essential if a balanced diet is maintained, emphasizing the importance of nutrient-rich food over isolated compounds.

Eating Disorders

Common Disorders

• Most common: Binge Eating Disorder, characterized by episodes of eating large quantities of food without control.

• Most dangerous: Anorexia Nervosa, known for the highest mortality rate, involves severe restriction of food intake and poses numerous health risks.

Symptoms/Behaviors

• Common behaviors include restricting food intake significantly, engaging in excessive exercising, and experiencing obsessive thoughts about food and body image.

Challenges of Discussion

• Many individuals with eating disorders find it difficult to talk about their condition due to feelings of shame, stigma, and fear of judgment, making it essential to approach the topic with sensitivity and understanding.

Possible Causes

• Genetics may predispose individuals to developing eating disorders, complicating treatment and recovery.

• Trauma and stressful life events can be triggers, creating a need for control through food or body image.

• Social and media pressure can contribute to unrealistic body standards, heightening feelings of inadequacy and low self-esteem.

Gluten Sensitivity

Condition

• Coeliac disease: An autoimmune disorder where ingestion of gluten leads to damage in the small intestine, requiring stringent dietary management.

Understanding

• Non-coeliac gluten sensitivity may present symptoms similar to coeliac disease but does not cause the same intestinal damage; it remains poorly understood, emphasizing the need for further research.

Impact on GI Tract

• Gluten can damage the villi in the small intestine, leading to malabsorption of nutrients, deficiencies, and gastrointestinal symptoms, and ultimately resulting in long-term health consequences such as osteoporosis and anemia.