HUNT 141 - Health (L16 - 20, 33-38)

What is calorimetry?

The measurement of energy expenditure

What is energy balance?

Energy = Energy in - Energy out

What is meant by “Energy out”?

Heat lost (radiant and evaporation)

What are the three ways to measure energy expenditure?

Direct, indirect calorimetry and doubly labelled water.

How does Indirect Calorimetry work?

Measure the volumes of O2 and CO2 expended and the uses a formula to calculate energy balance.

How does Direct Calorimetry work?

Stay in a room and everything expended is measured, and everything given to you is controlled.

What is Doubly Labelled Water?

Enriching the body with heavy hydrogen and heavy oxygen and then determining the difference in washout kinetics between both isotopes. Gold standard for energy expenditure measurements.

What is energy used for?

Resting energy, physical activity, thermic effect of food and growth.

What is Basal Metabolic rate?

Energy expended at rest to fulfill life sustaining functions

What % of total energy expenditure is Resting Energy Expenditure?

60%

What % of energy is used for digestion and processing of food?

~10%

What does a negative energy balance mean?

Energy out is greater than energy in and will lead to weight loss if consistent.

Overweight and Obesity are defined as

Abnormal or excessive fat accumulation that presents a risk to health. BMI of over 30.

Formula for calculating BMI

BMI = weight (kg) / height in m²

Normal BMI range

18.5 - 25

Overweight BMI

25 - 30

Obese BMI

>30

What are the associated health risks of excess body fat?

Chronic disease risk increases (diabetes, stroke, heart disease and some cancers)

What % of New Zealanders are overweight or obese in 2024/2025?

67.3%

What is the main cause of obesity?

Positive energy balance

How is Type 1 diabetes managed?

Medication, food choice and physical activity.

How is type 2 diabetes managed?

Food choices, physical activity and medication

What % of diabetics are type 2?

~90

What causes Type 1 diabetes?

The body attacks the cells that produce insulin which means not enough insulin is created.

What causes Type 2 Diabetes?

Cells do not produce enough insulin or do not recognise insulin is present.

Where is insulin produced?

In the pancreas

Where does glucose in the blood travel to when insulin causes glucose transporters to the surface of the cells?

Tissues, muscles and the liver.

What happens in Type 1 diabetics when glucose cannot get into cells and organs?

The organs cannot get glucose which is essential for energy production (ATP).

What is insulin resistance?

When insulin receptors stop responding appropriately to insulin and more insulin is needed to trigger translocation.

What happens when you have too much glucose in your blood?

It travels to the kidney and causes osmotic diuresis and polyuria which causes dehydration and polydipsia.

What % of the population have diabetes?

5 - 7 %

What are the long term health consequences of having diabetes?

Heart attack, kidney failure, amputation, stroke and blindness.

What are the risk factors for diabetes?

High BMI, CVD, family history and PCOS

What lifestyle changes reduce the risk of developing diabetes?

Reducing energy intake, increased physical activity, increased fibre intake and reductions in total and saturated fat.

What is the effect of exercise on blood glucose levels?

Muscle contraction can cause translocation of glut - 4 without insulin

How does physical activity reduce risk of diabetes?

Improved blood flow, increased glucose metabolism, muscles work better and increased expression and activity of glut - 4 and glycogen synthase

What are some functions of diabetes drugs?

Stimulate pancreas to work harder, increase cell sensitivity to insulin and can lower the renal threshold.

What are important dietary factors in diabetes prevention and management?

Energy intake, carbohydrate quality, foods and food groups and lifestyle.

What might be changed in the diet of an athlete compared to a non - athlete?

More grains, less vegetables, more fruit, more energy.

What is important in growing muscle?

Good distribution of nutrients, eating the right amount of protein, consistency with training, rest and good health overall.

What happens if an athlete is under fueling?

The may develop REDS (relative energy deficiency in sport), increased risk of injury, decrease in muscle mass, stress and nutrient deficiencies.

What is the role of a sports nutritionist?

Help athletes with their nutrition, recovery food prep, reflection and planning for athletes and more.

Indigenous people

The original people from a region, often have distinct social, culture and beliefs.

Indigenous food systems

Collective or communal view of land, resources and food practices. Knowledge, practices, traditions are transmitted intergenerationally. Spiritual connections with the envionment.

SDG

Sustainable development goals

Food security

The ability for individuals, households and communities to acquire appropriate and nutritious food on a regular and reliable basis.

Food sovereignty

The right of peoples to healthy and culturally appropriate food produced through ecologically sound and sustainable methods and their right to define their own food and agriculture systems

How does NZ address food security?

Food secure communities program which helps families who are food insecure and New Zealand food network who help reduce food waste.