Questions and Answers
What is the primary purpose of obtaining data for the chemical composition of foods?
What is a major problem in many developing countries?
Which group of people is most likely to suffer from specific deficiencies, such as protein, vitamins, and minerals?
What is the formula for calculating body mass index (BMI)?
Signup and view all the answers
What is the classification for a BMI of 32?
Signup and view all the answers
What is a characteristic of overnutrition in the developed world?
Signup and view all the answers
What is a common issue with the data obtained from food tables?
Signup and view all the answers
What is a potential application of the data obtained from food tables?
Signup and view all the answers
What is the main reason for the decline in death rates in this country?
Signup and view all the answers
Which region has the highest premature CVD death rate?
Signup and view all the answers
What is the main criterion for determining the requirement for a nutrient?
Signup and view all the answers
What is the primary purpose of establishing Dietary Reference Values (DRVs)?
Signup and view all the answers
What is the recommended percentage of total fat in the diet?
Signup and view all the answers
What is the Reference Nutrient Intake (RNI) based on?
Signup and view all the answers
What is the recommended percentage of sucrose in the diet?
Signup and view all the answers
What is the purpose of estimating the average requirement (EAR) for a nutrient?
Signup and view all the answers
What is one of the ways to change people's lifestyles?
Signup and view all the answers
What is the significance of the 95% confidence interval in determining the recommended nutrient intake?
Signup and view all the answers
What percentage of the population is likely to have their vitamin C needs met by an intake of 40mg per day?
Signup and view all the answers
What is the trend in deaths from stroke and coronary heart disease in low-income countries?
Signup and view all the answers
What is the role of the Committee of Medical Aspects of Food Policy (COMA) in determining nutrient requirements?
Signup and view all the answers
Why do we not use the same approach to determine energy requirements as we do for nutrient requirements?
Signup and view all the answers
What is the primary reason why it is difficult to be specific about individual energy and nutrient requirements?
Signup and view all the answers
What is the primary purpose of food tables, such as McCance and Widdowson's 'The Composition of Foods'?
Signup and view all the answers
Who published the first edition of 'The Chemical Composition of Foods' in 1946?
Signup and view all the answers
What is the term used to describe the amount of a nutrient needed to prevent deficiency?
Signup and view all the answers
What is the purpose of looking at the intake of a nutrient in groups of people with no deficiency and in groups of people with deficiency?
Signup and view all the answers
What was the original purpose of Robert McCance's research on the carbohydrate content of fruits and vegetables?
Signup and view all the answers
What is the current name of the publication that was previously known as 'The Chemical Composition of Foods'?
Signup and view all the answers
What is the term used to describe the amount of a nutrient that is associated with a marker of nutritional adequacy?
Signup and view all the answers
According to the 1980-2008 data, what percentage of adults globally were overweight or obese?
Signup and view all the answers
What percentage of children aged 5-15 in the UK eat five or more portions of fruit and vegetables a day?
Signup and view all the answers
What is the prevalence of obesity in 6-year-olds in the UK, according to the 2018 data?
Signup and view all the answers
What is the recommended maximum daily salt intake in the UK?
Signup and view all the answers
What is the percentage increase in deaths from stroke in men of British South Asian origin compared to the general population in the 1990s?
Signup and view all the answers
What is the target reduction in death rate from coronary heart disease and stroke in people under 75, set for 2010?
Signup and view all the answers
What is the percentage decline in the UK death rate from heart and circulatory diseases since 1961?
Signup and view all the answers
What is the percentage of adults in England who are obese, according to the 2021 data?
Signup and view all the answers
Study Notes
Nutrition and Metabolism
- Micronutrients consist of vitamins, essential minerals, essential amino acids, and essential fatty acids, which are required in small amounts (grams, milligrams, or micrograms per day).
- Nutrient requirements vary depending on age, gender, and activity levels, making it difficult to specify individual requirements.
- Guidelines for nutrient requirements are established for groups within the population.
Determining Nutrient Requirements
- The requirement for a nutrient is the amount needed to prevent deficiency, and societies expect more than this to ensure storage for times of low or no intake.
- The Food Standards Agency and the Committee on Medical Aspects of Food Policy (COMA) establish Dietary Reference Values (DRVs) for food, energy, and nutrients in the UK.
- DRV calculations involve studying the intake of nutrients in healthy groups, groups with deficiencies, and groups with clinical deficiencies, as well as intakes associated with nutritional adequacy markers.
Estimated Average Requirement (EAR) and Reference Nutrient Intake (RNI)
- The EAR is the notional mean requirement of a nutrient for a group of healthy individuals in a population.
- The RNI is two standard deviations above the EAR, sufficient to meet the needs of most of the population.
- The Lower Reference Nutrient Intake (LRNI) is two standard deviations below the EAR, indicating intakes of a nutrient below this level are almost certainly inadequate for most individuals.
Vitamin C Example
- The EAR for adults in the UK is 25mg, sufficient for the needs of approximately 50% of the population.
- The RNI for adults in the UK is 40mg, sufficient to meet the needs of approximately 95% of the population.
- The LRNI for adults in the UK is 10mg, indicating diets containing less than 10mg vitamin C per day would only provide sufficient for approximately 5% of the population.
Energy Requirements
- Energy requirements are not calculated in the same way as nutrient requirements, as they vary depending on individual factors such as age, gender, and activity levels.
Food Tables
- Food tables, such as McCance and Widdowson's "The Composition of Foods Integrated Dataset", provide data on the chemical composition of foods.
- The data is obtained by analyzing many samples of a particular food and calculating the mean content of various nutrients.
- Although the data may not be strictly accurate, it can still be useful in analyzing individual nutrient and energy intakes and formulating diets for specific groups.
Undernutrition and Overnutrition
- Undernutrition is a major problem in developing countries, particularly in South Asia, sub-Saharan Africa, and parts of South America.
- In the developed world, undernutrition is often due to specific deficiencies, such as protein, vitamin, or mineral deficiencies.
- Main groups at risk of undernutrition include the elderly, young people on junk food, some Asian women and children, slimmers, and people with eating disorders.
- Overnutrition is a major problem in the developed world, characterized by excessive consumption of fat, sugar, salt, and overall food intake.
Body Mass Index (BMI)
- BMI is calculated by dividing weight in kilograms by height in meters squared (kg/m2).
- BMI categories include:
- Normal (18.5-24.9)
- Overweight (25-29.9)
- Obesity grade 1 (30-34.9)
- Obesity grade 2 (35-39.9)
- Obesity grade 3 (>40)
Consequences of Overnutrition
- Consequences of overnutrition include cardiovascular disease, stroke, some cancers, hypertension, diabetes type 2, gallstones, dental caries, gout, infertility, sleep apnoea, and surgical risk.
- Risks for cardiovascular disease include high blood cholesterol, hypertension, smoking, inactivity, and obesity.
- High blood pressure is often related to high salt intake, and some groups, such as those of South Asian origin, are at particular risk.
- Coronary heart disease and stroke are significant health problems, with the UK death rate from heart and circulatory diseases declining by more than three-quarters since 1961.
Recommendations and Way Forward
- Recommendations for changing the percentage contribution of nutrients to the total energy of the diet include:
- Total fat: 30-33%
- Saturated fat: no more than 10%
- Protein: 10-15%
- Sucrose: no more than 10% (5% in 2014)
- Alcohol: no more than 5%
- The way forward involves understanding why people choose to eat and drink what they do, and how they can change, with solutions including education, clear labelling of food products, support for deprived groups, school food schemes, role models, control of advertising, and pressure on the food industry.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Learn about micronutrients, including vitamins, essential minerals, amino acids, and fatty acids, and how to determine daily requirements. Part of MBBS stage 1 nutrition and health course.
