Nutrition 2P20 - Midterm 1

Nutrition definition:

A hard science that is associated with and integrated with behavioural, sociological, economic, and environmental sciences

Is the understanding of nutrition constantly growing?

Yes

Is nutrition integral to the kinesiology field?

Yes

How can nutrition help prevent, treat, or manage chronic disease?

• Better blood glucose

• Better blood pressure

• Better cholesterol levels

• Better body weight

How can we use diet to optimize our wellbeing across our lifespan?

A diet supports…

• Growth

• Energy

• Immunity

• Bone health

• Healthy aging

Why is nutrition important for human performance?

Nutrition provides energy and nutrients needed for training, recovery, muscle growth, hydration, and improved performance.

How has the goal of the Canadian diet changed over time?

Past: Obtaining all the nutrients needed for good health and preventing deficiencies

Present: Limit consumption to prevent obesity and chronic disease

What influences changes in Canadian food choices and consumption?

• Food industries

• Grocery industries

• Individual choices

• Socioeconomic factors

• Political factors

What is the CCHS?

The Canadian Community Health Survey

What does the CCHS do?

Collects info about the health, lifestyle, diet, and behaviours of Canadians.

How healthy is the Canadian diet? List 5 facts.

• Some Canadians are not meeting servings for grains

• Most Canadians meet servings for meat and alternatives

• Canadians eat a lot of highly processed foods

• Abundance of calories, sodium, and fat is normal

• Individuals food patterns are not focused on long term wellness

How do we get more people to make healthy choices in food?

• Nutritional literacy

• Improved knowledge translation (research)

• Transparency of food producers for consumers

• More

How many nutrients are essential to human life?

45

List non-essential nutrients.

• Phytochemicals

• Antioxidants

• Other bioactive organic compounds

How many classes of nutrients are there?

6

What are the classes of nutrients?

1. Carbohydrates

2. Lipids

3. Protein

4. Water

5. Vitamins

6. Minerals

Key things to know about Carbohydrates:

• 4 kcal/g

• Sugars

• Starches (plant)

• Glycogen (animals store carbs as this)

• Fibre

Key things to know about Lipids:

• 9 kcal/g

• Triglycerides

• Cholesterol

• Phospholipids

Key things to know about Protein:

• 4 kcal/g

• Built with amino acids

• Unique shapes/functions

• All enzymatic reactions

What type of nutrient is Water?

• Macronutrient (because the human body requires it in large, gram-scale quantities every single day)

Key things to know about Vitamins:

• No kcal

• Organic molecules (contain carbon)

• 13 vitamins

Key things to know about Minerals:

• No kcal

• Inorganic molecules (does not contain carbon)

• 7 major minerals

• Many trace minerals

What are fortified foods?

They are everyday food products that have extra vitamins and minerals added to them during manufacturing to improve their nutritional value.

List the 3 functions of nutrients:

1. Energy supply

2. Form structures

3. Regulate physiological processes

Imbalances in food intake in either direction are called…

Malnourishment

How do nutrients regulate physiological processes?

Supply and mediate…

• Critical body systems

• Organ function

• Metabolic pathways

• Adaptations to physiological stressors

7 factors affecting food choices

1. Food availability

2. Culture and family

3. Social acceptability

4. Personal preference

5. Psychological and emotional factors

6. Health concerns

7. Media/advertising

What is a nutrient-dense diet?

A healthy diet that includes plenty nutrient-dense foods such as broccoli.

Whats a EDNP food?

A Energy Dense, Nutrient Poor food

What should inform our food choices?

• Evidence

• Reliability

• Risk of bias

• Acceptability

Does increased dietary saturated fat acid (SFA) intake lead to cardiovascular disease (CVD)?

Recent and developing evidence has proven this association is incomplete and maybe incorrect. However, replacing sat fat with other lipids may reduce CVD risk.

Saturated fat and cholesterol have been discouraged to promote a cardio protective effect. How has our modern diet changed because of this?

• For many years people have been told low fat/chloesterol foods are healthier

• People were getting unhealthy because the natural fats were being removed from foods

• People then overcompensated after finding this out, ultra low carb / high fat dietary patterns emerged

What studies estimate nutrient requirements and observe deficiencies?

• Depletion/Repletion/Balance feeding studies

Whats an intervention?

A specific action, treatment, or program introduced by researchers to change a situation or improve an outcome.

Laboratory studies aim to show what?

They aim to show a causation effect of an intervention on a specific outcome.

A downside to laboratory studies:

Controlling the variables more in more causes makes you lose real world complexity/validity.

List the major categories of nutrition studies:

• Intervention studies

• Observational studies (non-interventional)

What are confounders?

Factors that affect both variables, making it harder to determine whether one variable actually causes the other. For example, people who exercise more may also eat healthier. If they have lower rates of heart disease, you can't know whether it's from their exercise, their diet, or both.

Prospective vs Retrospective

• Prospective: Study moves forward from exposure to outcome

• Retrospective: Study looks backward from outcome to past exposure

*8 aspects of intervention studies:

• Randomization of control/treatment groups

• Single or double (publishers don’t know) blinding

• More controlled confounders

• Placebo (calcium and plain pill look the same)

• Actively intervene the lives of people

• Tests the hypothesis from observations

• Strict guidlines

• High quality (gold standard) research for cause-effect

Whats a clinical trail?

A intervention study that is conducted on human participants to evaluate the safety, efficacy, or medical impact of a health related intervention.

*4 aspects of observational studies:

• Observe relationships between diet and health

• Produce correlations/associations

• Confounding factors are less likely controlled for

• Includes prospective and retrospective measurements

3 types of observational studies:

• Cohort

• Cross-sectional

• Case-control

Aspects of a cohort study (3):

• Measurements collected in a group over time (longitudinal)

• Prospective

• Participants are selected based on level of exposure to some variable

Limitations on cohort studies:

• Does not provide the same info as clinical tails (intervention)

• Time consuming and expensive

• Does not resolve problems with confounding variables

Aspects of a cross-sectional study (5):

• Measurements collected in a group

• Can include both past and present variables

• Not prospective or retrospective

• Outcomes and exposures are measured at the same time (outcome is cholesterol levels in blood, exposure is how often eggs are consumed)

• Measures what percentage of a population has a specific habit (exposure) or condition (outcome) at one specific moment

Limitations of cross-sectional studies:

• Needs a large number of people

• High possibility for confounding variables

• Cannot establish causation (only correlation)

Aspects of a case-control study (3):

• Measurements collected in 2 groups of people (experimental and control)

• Often retrospective

• Measures how much more or less likely the experimental group (the cases) is to have the outcome of interest (the past exposure) compared to the controls

Limitations on case-control studies:

• Retrospective, meaning recall (could lead to errors/inaccuracy)

• Both groups aren’t going to be the same no matter what

Does most research identify a simple cause-effect relationship?

No

What does a study's experimental design and analysis type determine about its outcomes?

It determines if we can claim causation or just correlation

Whats the confirmation bias?

A cognitive bias that causes you to look for, interpret, and remember information in a way that proves what you already believe, while completely ignoring or downplaying evidence that says you are wrong.

Rank the 4 study designs by level of evidence (Highest to Lowest):

1. Clinical Trials

2. Cohort Studies

3. Case-Control Studies

4. Cross-Sectional Studies

Label these studies:

1. Cross-sectional study

2. Case-control study

3. Prospective cohort study

The primary value of Canada’s nutritional guidelines is to provide reliable information to guide food choices and behaviour, while also…

• Providing reliable and trustworthy information

• Agreement from research leaders across many fields

• Ensuring practicality and acceptability

• Implementation strategy and personalization

• A platform with ongoing scrutiny, revision, and refinement

What is blinding? What type of research is it in? Why is it difficult to do in nutritional science research?

• Blinding means keeping participants and/or researchers unaware of which treatment or group someone is in

• It is a intervention study

• People can see, smell, and taste what they are eating, making it hard to introduce placebos in diets (unlike pills, you cannot fake food like steak vs. broccoli)

When and where were the 1st nutritional recommendations?

Britain in the 19th century (1800’s) induced by the industrial revoulution

Who makes the international health recommendations?

World Health Organization (WHO)

What is Eating Well with Canada’s Food Guide designed to do?

Promote health and a balanced diet, reflecting the Dietary Reference Intake (DRI) values

What are Dietary Reference Intakes (DRI) designed to do, and who created them?

Promote optimal health and prevent deficiencies, developed jointly by the USA and Canada

How are DRIs developed for nutrients?

Estimates from many studies are combined to find the average nutrient requirement

Why can nutrient requirements be estimated using a bell curve?

Most people's nutrient requirements (height, IQ, weight) follow a normal (bell curve) distribution, where most people are near the average

What is the EAR?

• Estimated Average Requirement

• The estimated requirement of a nutrient to meet the needs of half of the healthy population (50%) of a particular sex and life-stage

What is the RDA?

• Recommended Dietary Allowance

• The recommended target intake level of a nutrient for an individual (EAR + 2 SD) of a particular sex and life-stage

Label the components of the graph:

1. EAR

2. RDA

3. Number of People

4. Daily Requirement

What is the risk for High Intake vs. Low Intake regarding a certain nutrient?

• High: Risk of adverse outcomes

• Low: Risk of deficiency

What is AI?

• Adequate Intake

• The recommended amount (range) of nutrient for an individual

What is TUL?

• Tolerable Upper-Intake Level

• The maximum daily intake, unlikely to cause adverse effects

Label the components of this graph:

1. EAR

2. RDA

3. AI

4. TUL

5. Risk of Inadequacy (not good enough)

6. Risk of adverse effects

7. Nutrition intake level

What is used when EAR/RDA/TUL are not precisely determined?

Adequate Intake (AI)

List the 2 types of energy recommendations:

• Estimated Energy Requirement (EER)

• Acceptable Macronutrient Distribution Range (AMDR)

What is EER?

• Estimated Energy Requirement

• The amount of energy (calories) needed to maintain energy balance

What is AMDR?

• Acceptable Macronutrient Distribution Range

• The recommended % of calories that should come from carbs (45-65%), protein (10-35%), and fat (20-35%)

Is it easy to get a plenty and quality evidence to make Chronic Disease Risk Reduction (CDRR) statements or recommendations?

No, It is very difficult to obtain

What were Canada’s Official Food Rules (1942) created for?

• Reducing malnutrition during wartime rationing and widespread poverty

• Issued by the Department of National Health and Welfare

What was the main focus of early Canadian food guidelines?

• Encouraging variety and diversity to prevent nutrient deficiencies

• No concern with overeating or energy intake

What were key features of Canada’s Food Guide in 1992 and later updates?

• 1992 used a rainbow with 4 food groups showing a hierarchy

• Culturally specific foods

• Later guides added physical activity, water as the preferred fluid, food-label reading, and different language versions

Canada’s Food Guide 2019 guidelines:

1. Nutritious foods are the foundation for healthy eating

2. Processed/prepared foods and beverages high in sodium, free sugars, and saturated fat should be limited

3. Food skills support healthy eating

What does % Daily Value (%DV) on a food label tell you?

• It tells you the fraction of your daily value in one serving (5% = a little, 15% = a lot)

• Based on a 2,000 kcal diet

• A simple indicator of nutrient density

Is packaging labeling resolved so far?

No

What additional health claims may appear on labels?

1. Nutrient-content

2. Disease-risk reduction

3. Nutrient-function

Who regulates food labeling?

The Canadian Food Inspection agency (CFIA)

What do “source,” “good source,” and “excellent source” mean?

• Source: 5%+ DV

• Good source: 15%+ DV

• Excellent source: 25%+ DV

What do “sodium-free” and “low-fat” mean?

• Sodium-free: Up to 0.5 g per serving

• Low-fat: Up to 3 g fat per serving

What do “reduced/little/few” and “lean/extra lean” mean?

• Reduced/less/light: Up to 25% less of the nutrient than a similar product

• Lean: <10 g fat/100 g

• Extra lean: <7.5 g fat/100 g

What is a disease risk reduction claim?

A claim about how a food/nutrient affects the risk of developing a disease or condition (Calcium → osteoporosis, Sodium → hypertension)

What is a function claim?

• Describes how a nutrient or dietary ingredient helps maintain normal body structure or function

• It must mention the nutrient and the food and is not necessarily disease-related

• Example: Milk provides calcium, which helps maintain healthy bones.

What does the Natural Health Products Directorate regulate?

• Vitamin/mineral supplements

• Essential fatty acids

• Probiotics

• Herbal remedies

• Traditional medicines

• Homeopathic products

Is characterizing population-level dietary patterns/choices easy?

No, it is difficult because of behaviour diversity and challenges with measurement

What are Food Disappearance Surveys used for?

To monitor food supply as an indirect estimate of intake and consumption patterns

What is the CHEI and what does it do?

• Canadian Healthy Eating Index

• Measures how closely a person’s diet follows Canada’s Food Guide

What is the most recent average CHEI score?

58.8%

What are 4 challenges in determining dietary intakes?

• Recall imprecision

• Under/over estimation

• Non-typical day recording (weekend vs. weekday, birthday)

• Reporting consistency

What are 4 techniques are used to assess nutritional status?

• Anthropometrics (measurement of size/proportions/physical characteristics of the body)

• Physical/medical exams

• Lab tests

• Interviews

What are 4 dietary tools are used to assess dietary intake?

• 24-hour recall

• Food diary/intake record

• Food frequency questionnaire

• Full diet history

Food-intake estimates of nutrient deficiencies: Do they under or overestimate?

Underestimate

Even when energy abundance is prevailing (more than enough calories), what is common?

Nutrient deficiencies