Nutrition Week 13 Tutor: Linda York Tutor: Linda York

Learning Outcomes Identify rich sources of carbohydrates, proteins, fats, fat soluble vitamins A and D, water soluble vitamin C and mineral ions (6) Identify the need for a balanced diet (5) Investigate the comparison of the energy content of nutrients (8) Analyse and interpret the information on a food label (17) Investigate the effects of reducing or increasing the various components in the diet (12) Linda York

Learning Outcomes Identify the benefits of fibre in the diet (11) Explain the consequences of calcium and iron deficiency (9) Explain the consequences of excess salt and sugar (10) Investigate the issues involved in adding chemicals to food and water (16) Investigate quantitative tests for energy content (18) Evaluate quantitative and qualitative data on food analysis (19) Linda York

Food we eat Take a few minutes to write down what you had to eat and drink today. Linda York

Rich sources of carbohydrates, proteins, fats, fat soluble vitamins A and D, water soluble vitamin C and mineral ions. Carbohydrates - Proteins - Fats - Vitamins A and D - Vitamin C - Mineral Ions - Consider the foods within these groups – you have 5 minutes. Linda York

The Energy Content of Nutrients Carbohydrate 1 gram = 16 kJ Protein 1 gram = 17 kJ Fat 1 gram = 37 kJ Linda York What do you think the following energy figures are? Carbohydrate 1 gram = ? kJ Protein 1 gram = ? kJ Fat 1 gram = ? kJ What do you think the following energy figures are? Carbohydrate 1 gram = ? kJ Protein 1 gram = ? kJ Fat 1 gram = ? kJ

Food Labelling Linda York

Food labelling Linda York

Diet Problems Having too much or too little of any type of food in your diet can cause you health problems. Body Mass Index indicates if you are under or overweight. The body mass index (BMI) is used as a guide to help decide whether someone is underweight, normal, overweight or obese. It is calculated from their height and weight. Linda York

BMI How to calculate BMI body mass (in kg) (height)² (in metres²) Body Mass Index Weight Description below underweight 18.5 – normal 25 – overweight 30 – 40 - moderately obese above 40 - severely obese Linda York

BMI BMI isn’t always reliable. Athletes have lots of muscle, which weighs more than fat, so they can come out with a high BMI even though they are not overweight. Linda York

BMI To calculate your BMI, you divide your weight (in kilograms) by the square of your height (in metres). So, for example, if you weigh 70 kg and are 1.75 metres tall, your BMI is 70 ÷ (1.75 x 1.75), which equals Linda York

BMI The answer is Linda York What is the BMI of a person weighing 85 kg and with a height of 1.81 m?

Too much food  Obesity is defined as being 20% (or more) over your recommended body weight.  Too much sugary or fatty food and too little exercise are the main causes of obesity.  People can also be obese due to an underactive thyroid gland, but this problem isn’t common.  Obesity can increase the risk of diabetes, arthritis, high blood pressure, coronary heart disease (CHD) and even some forms of cancer e.g. breast cancer. Linda York

Too little food  This can be a lack of one or more specific types of food, or not enough of any sort (starvation).  Young children, the elderly and women tend to suffer most and the effects vary depending on what foods are missing from the diet.  Common problems include slow growth (in children), fatigue and poor resistance to infection. Linda York

Too little Protein  Eating too little protein can cause a condition called kwashiorkor.  A common symptom is a swollen stomach.  Kwashiorkor is especially common is poorer developing countries – protein rich foods are often too expensive to buy.  Children need a greater proportion of protein than adults (for growth), so they may be more likely to suffer. Linda York

Malnutrition Malnutrition can be the result of an eating disorder. Even in developed countries, some psychological disorders can cause under-nutrition, e.g. anorexia nervosa and bulimia nervosa. Linda York

Malnutrition  Anorexia nervosa leads to self starvation.  Bulimia nervosa involves bouts of binge eating, followed by self-induced vomiting.  They are both usually caused by low self- esteem and anxiety about body fat – sufferers have a poor self-image. Linda York

Anorexia and Bulimia These disorders can cause a host of other illnesses, e.g. liver failure, kidney failure, heart attacks, muscle wastage, low blood pressure and mineral deficiencies. Both disorders can be fatal. Linda York

Dietary requirements Dietary requirements with respect to the amounts of energy, protein, vitamins and mineral salts may change due to: – growth – pregnancy – amount of physical exercise – disorders such as diabetes, high blood pressure and heart disease. Linda York

Benefits of fibre in the diet Although fibre is not strictly a nutrient, it is a very important component of our diet. Fibre rich foods are: wholemeal/wholegrain foods such as bread, cereal and flour, brown rice, wholemeal pasta, oats, beans, peas, lentils, grains, seeds, fruit and vegetables. Linda York

Fibre Fibre is only found in foods that come from plants. Linda York

Too much! Sugar Salt High blood pressure  heart disease  heart attack Linda York Obesity  diabetes

Calcium and iron deficiency Calcium Softer bones and teeth. Poor blood clotting. Iron Less haemoglobin produced  less oxygen carried to cells  less energy released  person is tired (anaemia) Linda York

Adding chemicals to food and water Antioxidants - make foods last longer by helping to stop the fats, oils and certain vitamins from combining with oxygen in the air - this is what makes food taste 'off' - become rancid and lose colour. Preservatives - help stop food 'go off' and mean that food can be kept safe for longer. Most food that has a long shelf-life is likely to include preservatives, unless another method of preserving has been used such as freezing, canning or drying. Linda York

Adding chemicals to food and water Issues include:  freedom of choice, and  mass medication Linda York

Dietary requirements for special populations Having a balanced diet isn’t just as simple as making sure that you get all of the essential nutrients. The amount of each nutrient that you require will depend on your body’s individual needs. Linda York

Homework 1. Complete the handouts for next week. 2. REVISE! Linda York