Translating nutrition: From nutrients to foods
The preceding chapters have provided us with an overview of the nutrients needed for good health and performance. We now understand why we need these nutrients; however, planning a nutritious diet is a complex task because we consume these nutrients as part of whole foods within the context of a diet influenced by a range of sociocultural, environmental and individual factors. The factors that influence our diet will be discussed in later chapters. In this chapter, we will explore how to meet our nutrient requirements through food and identify good food choices to meet the macro- and micronutrient requirements of athletes.
LEARNING OUTCOMES
Upon completion of this chapter you will be able to:
• understand the rationale for food-based dietary recommendations
• describe how whole food diets can be used to meet individual nutrient requirements
• identify food sources of macro- and micronutrients required by athletes
• recommend specific foods and food combinations to meet individual nutrient requirements.
FOOD IS MADE UP OF MORE THAN NUTRIENTS
Chapters 4 and 5 have described the role of a number of nutrients for health and performance. It is tempting to try to put together a magic bullet nutrient supplement to meet these needs. Indeed, we can obtain all of our micronutrient requirements from nutrient supplements. However, when we aim to consume our nutrient requirements in the form of food, we gain more than we would if we consumed supplements alone.
There are many benefits of consuming nutrients as part of whole foods rather than from supplements. To begin with, we know that some nutrients are absorbed better as part of a whole food. For example, the lactose in milk may assist with calcium absorption. Foods can also have a synergistic effect in promoting nutrient absorption and function. When plant sources of iron, such as beans, are consumed with a source of vitamin C, such as orange juice, the vitamin C assists with iron absorption and therefore increases its availability in the body. Many nutrients are also more effective when consumed as part of a whole food diet. Omega-3 fatty acids derived from eating fish are often found to be more effective in preventing conditions such as ischaemic heart disease than omega-3 supplements alone. Whole foods also often bundle nutrients in a convenient package. For example, dairy foods such as milk contain not only calcium but also magnesium and phosphorus, which work with calcium to help build and maintain strong bones. Alongside vitamins and minerals, foods provide a range of other compounds with beneficial actions, such as fibre and phytonutrients. Foods also often conveniently provide nutrients where they are needed. Wholegrains are good sources of B vitamins, and B vitamins are needed to help derive energy from the carbohydrates in wholegrains. Vitamin E is found in plant oils and helps to prevent oxidisation of the oil and minimise damage from free radicals in our bodies. Whole foods also have the added benefit of providing pleasure, creating an opportunity for socialisation and promoting rest and relaxation during eating. On the other hand, supplements can be expensive, run the risk of toxicity with overconsumption, and may contain unwanted compounds or contaminants, which is particularly problematic for many competitive athletes.
Synergistic
The interaction of two or more substances, in this case nutrients, to produce a combined beneficial effect that is greater than the sum of its individual effects.
Ischaemic heart disease
Also called coronary artery disease, a group of diseases including angina, myocardial infarction and sudden coronary death. The pathogenesis of this disease is due to the restriction of blood flow in the coronary arteries that results in reduced blood flow, and hence oxygen supply, to the heart muscle.
Phytonutrients
Substances found in plant foods that have a beneficial health effect, such as lycopene in tomatoes and anthocyanin in blueberries.
Toxicity
Occurs when nutrients are consumed in very high amounts and cause health problems. For example, very high levels of vitamin A consumed by pregnant women have been linked to birth defects. Toxicity is most likely to occur with overconsumption of fat-soluble vitamins and some minerals.
Now, with an understanding of the importance of consuming our nutrients as part of a whole food diet, we need to learn what foods to consume to meet our nutrient requirements.
DIETARY GUIDELINES
Accredited Practising Dietitians
Health professionals who have completed a university degree in dietetics and have been accredited by the Dietitians Association of Australia to provide a range of nutrition-related services, including individualised medical nutrition therapy. In New Zealand, these professionals are known as Registered Dietitians.
Accredited Sports Dietitians
Accredited Practising Dietitians who have completed extra training and practical experience in sports nutrition and are accredited by Sports Dietitians Australia to provide nutrition services for athletes.
Australia and New Zealand each have their own evidence-based dietary guidelines designed to help the population make food choices that will meet their dietary requirements and promote good health. The Australian Dietary Guidelines (NHMRC 2013) and the New Zealand Eating and Activity Guidelines (Ministry of Health 2015) provide broad public health recommendations that have been developed by expert panels based on the analysis of data from published research. The advice in these guidelines is intended for healthy individuals to maintain good health. Individuals with medical conditions that require specialised medical nutrition therapy should seek advice from an Accredited Practising Dietitian. Athletes with specific dietary requirements may use the dietary guidelines as a starting point and should seek individualised advice from an Accredited Sports Dietitian.
Box 6.1: Australian Dietary Guidelines
GUIDELINE 1
To achieve and maintain a healthy weight, be physically active and choose amounts of nutritious food and drinks to meet your energy needs.
• Children and adolescents should eat sufficient nutritious foods to grow and develop normally. They should be physically active every day and their growth should be checked regularly.
• Older people should eat nutritious foods and keep physically active to help maintain muscle strength and a healthy weight.
Enjoy a wide variety of nutritious foods from these five groups every day:
• plenty of vegetables, including different types and colours, and legumes/beans
• fruit
• grain (cereal) foods, mostly wholegrain and/or high-cereal fibre varieties, such as breads, cereals, rice, pasta, noodles, polenta, couscous, oats, quinoa and barley
• lean meats and poultry, fish, eggs, tofu, nuts and seeds, and legumes/beans
• milk, yoghurt, cheese and/or their alternatives, mostly reduced fat (reduced fat milks are not suitable for children under the age of two years).
And drink plenty of water.
GUIDELINE 3
Limit intake of foods containing saturated fat, added salt, added sugars and alcohol.
a. Limit intake of foods high in saturated fat such as many biscuits, cakes, pastries, pies, processed meats, commercial burgers, pizza, fried foods, potato chips, crisps and other savoury snacks.
• Replace high-fat foods which contain predominantly saturated fats such as butter, cream, cooking margarine, coconut and palm oil with foods that contain predominantly polyunsaturated and monounsaturated fats such as oils, spreads, nut butters/pastes and avocado.
• Low-fat diets are not suitable for children under the age of two years.
b. Limit intake of foods and drinks containing added salt.
• Read labels to choose lower-sodium options among similar foods.
• Do not add salt to foods in cooking or at the table.
c. Limit intake of foods and drinks containing added sugars such as confectionery, sugar-sweetened soft drinks and cordials, fruit drinks, vitamin waters, energy and sports drinks.
d. If you choose to drink alcohol, limit intake. For women who are pregnant, planning a pregnancy or breastfeeding, not drinking alcohol is the safest option.
Encourage, support and promote breastfeeding.
GUIDELINE 5
Care for your food; prepare and store it safely.
Source: NHMRC 2013.
Box 6.2: New Zealand Eating and Body Weight Statements
EATING STATEMENT 1
Enjoy a variety of nutritious foods every day, including:
• plenty of vegetables and fruit
• grain foods, mostly wholegrain and those naturally high in fibre
• some milk and milk products, mostly low and reduced fat
• some legumes, nuts, seeds, fish and other seafood, eggs, poultry and/or red meat with the fat removed.
EATING STATEMENT 2
Choose and/or prepare foods and drinks:
• with unsaturated fats (canola, olive, rice bran or vegetable oil or margarine) instead of saturated fats (butter, cream, lard, dripping, coconut oil)
• that are low in salt (sodium); if using salt, choose iodised salt
• with little or no added sugar
• that are mostly ‘whole’ and less processed.
EATING STATEMENT 3
Make plain water your first choice over other drinks.
EATING STATEMENT 4
If you drink alcohol, keep your intake low. Stop drinking alcohol if you could be pregnant, are pregnant or are trying to get pregnant.
EATING STATEMENT 5
Buy or gather, prepare, cook and store food in ways that keep it safe to eat.
Making good choices about what you eat and drink and being physically active are also important to achieve and maintain a healthy body weight.
Being a healthy weight:
• helps you to stay active and well
• reduces your risk of developing Type 2 diabetes, cardiovascular disease and some cancers.
If you are struggling to maintain a healthy weight, see your doctor and/or your community health care provider.
Source: Ministry of Health 2015.
In addition to these broad statements, the dietary guidelines provide practical tools to assist individuals in putting together a diet that is consistent with the dietary guidelines and meets their nutrient requirements. The Australian Guide to Healthy Eating and the New Zealand Serving Size Advice build upon the Nutrient Reference Values (NHMRC et al. 2006) to provide practical food selection advice. These food selection guides are developed based around groups of foods with similar key nutrient profiles, such as wholegrains. A food modelling system is then used to determine how much of each food group should be consumed to meet an individual’s nutrient requirements and only enough energy to meet the needs of the smallest and least active person. This recommended eating pattern is called a foundation diet, and it meets one’s minimum nutrient needs. Athletes often expend more energy and therefore have higher energy requirements, so they may need to consume more serves of each of the food groups to meet their energy and nutrient requirements. This complete diet is known as a total diet. Total diets should be developed for individual athletes based on their size, sex, body composition, activity levels, individual preferences and sport-specific requirements. For example, some athletes may prefer or require more carbohydrate-rich wholegrain foods, while others require more protein-rich meat and alternatives. The food selection guides can be found online at the Australian government’s Eat for Health website (www.eatforhealth.gov.au/).
Foundation diet
A food-modelling system that determines how much of each food group should be consumed to meet an individual’s nutrient requirements and only enough energy to meet the needs of the smallest and least active person.
Total diet
The dietary pattern that is determined, using the Foundation Diet as the basis, to account for additional energy and nutrient needs for an individual.
Many countries have their own dietary guidelines and food selection guides, based on their own best evidence and culturally appropriate foods. You will learn more about culturally diverse dietary patterns in Chapter 25.
Figure 6.1. Australian Guide to Healthy Eating
Source: NHMRC 2013.
FOOD SOURCES OF MACRONUTRIENTS
Carbohydrates are found in foods in the form of starch or sugar. Starchy foods include:
• breads, rolls, wraps, bagels, muffins and crumpets
• breakfast cereals and porridge
• rice, pasta and noodles
• potato, sweet potato and corn.
Sugary foods include:
• lollies
• fruit (in the form of fructose)
• milk (in the form of lactose)
• table sugar, honey and maple syrup.
Some carbohydrate foods provide more nutrition than others. Lollies and added sugars can provide enjoyment and increase the palatability of foods, but are not health-promoting as they contain no or very little nutrition (these foods are referred to as energy dense and nutrient-poor). For good health, it is recommended that we consume foods that fit within the food groups in the food selection guides and choose the higher fibre options, such as wholegrain bread, brown rice and potatoes in their skins. For athletes, the timing of fibre intake is important; high-fibre foods should be avoided in the hours leading up to a training session to avoid gastrointestinal discomfort. Some people also experience unpleasant symptoms, such as gas, bloating, constipation and diarrhoea, after consuming some types of carbohydrates. Fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) are poorly absorbed by some individuals and can cause these unpleasant symptoms. For others, these symptoms may occur following consumption of gluten-containing foods. Gluten is a protein contained in some carbohydrate-rich foods, such as wheat-based breads and cereals. Strategies for managing FODMAP intolerance and other gastrointestinal problems will be discussed in Chapter 23.
Energy dense
Foods that contain high levels of energy with little or no nutrients.
Protein is found predominantly in foods derived from animals. Meat, poultry, fish, eggs and dairy products are all good sources of protein. However, individuals may limit their intake of animal sources of protein due to the cost, or their personal preference to avoid animal food sources for ethical, environmental or religious reasons. Animal sources of protein may also contain high levels of saturated fats, but intake of these fats can be minimised by selecting lean cuts of meat, skinless poultry and reduced fat dairy products. Nuts, seeds and legumes such as beans, lentils and chickpeas are good options for vegetarian athletes and those looking for lower fat or less expensive sources of protein. It is important to keep in mind that vegetable sources of protein are considered incomplete (that is, they do not contain all of the essential amino acids) or limiting (that is, they contain very small amounts of the essential amino acids relative to requirements). So, vegetarians should aim to consume a variety of protein-containing foods to obtain all essential amino acids. See Table 6.1 for examples of complementary proteins.
These foods can be simply combined to make complete proteins—for example, peanut butter (legumes) on toast (grains), or beans (legumes) and rice (grains).
Leucine
An essential amino acid, which is required for muscle protein synthesis.
The amino acid leucine plays a role in stimulating muscle protein synthesis, making it an important part of the diet for
athletes, especially masters athletes (Chapter 19) and those recovering from injury (Chapter 24). Whey protein, which makes up 20 per cent of the protein in dairy foods, is a good source of leucine, so dairy foods and whey protein supplements are popular among athletes.
To reduce their risk of developing chronic diseases, it is important for athletes and active people to limit their intake of saturated fats and consume moderate amounts of unsaturated fats. Saturated fats are found predominantly in animal products; they are in the fat on red meat, in chicken skin and in cream. Palm and coconut oils are also sources of saturated fat and are often found in commercially prepared baked goods and deep-fried foods. Where possible, these fats should be replaced with health-promoting mono- and polyunsaturated fats. Monounsaturated fats are found in olive oil and walnuts and are known to help reduce the risk of developing chronic diseases such as diabetes and cardiovascular disease. Omega-3 polyunsaturated fats are found predominantly in fish and help to reduce inflammation, which can support a number of healthy functions including joint health and circulation. For athletes with lower energy requirements, intake of fat may need to be minimised to limit total energy intake. Table 6.2. lists foods that are good sources of macronutrients.
Table 6.1. Food sources of complementary proteins
| Food | Limiting amino acid(s) | Complementary food |
| Legumes | Methionine | Grains, nuts and seeds |
| Nuts and seeds | Lysine | Legumes |
| Grains | Lysine, threonine | Legumes |
| Corn | Tryptophan, lysine | Legumes |
Source: Adapted from American Society for Nutrition 2011.
Table 6.2. Good food sources of macronutrients for athletes
| Foods rich in carbohydrate | Foods rich in protein | Foods rich in healthy fats |
| Bread | Milk | Avocado |
| Rice | Eggs | Nuts |
| Pasta | Beef | Fish |
| Breakfast cereal | Chicken | Peanut butter |
| Porridge (oats) | Fish | Olive oil |
| Sweet potato | Tofu | Canola oil |
FOOD SOURCES OF MICRONUTRIENTS
Every time we eat we have an opportunity to nourish our bodies. Athletes and active people should choose nutrient-dense foods as often as possible to support their bodies’ increased nutrient requirements. Active people may have increased demands for calcium, iron, B vitamins and antioxidants, including vitamins C and E. With careful planning, these needs can be met with a whole food diet.
Some athletes may choose to take vitamin and mineral supplements in an effort to meet their nutrient needs. All athletes should be encouraged to consume a whole food diet that aligns with dietary guidelines to meet their nutrient needs; however, should they have concerns about their dietary intake, a multivitamin and mineral supplement may be considered. The supplement should not contain more than the recommended dietary intake of each nutrient unless advised by a doctor or dietitian.
It is important to understand that individual foods can be sources of many different nutrients. For example, milk contains protein, carbohydrate and calcium as well as other vitamins and minerals. You can use the table below to identify foods that will meet multiple nutrient needs. It is important to also consider that some foods that are good sources of some nutrients may also contain large amounts of unhealthy fats, sugars or salt. For example, commercial peanut butter is a source of protein but is usually made with added fats, sugar and salt. When using Table 6.3, keep in mind that the nutrient values presented are per 100 grams of food, which may not correspond to the amount of food you actually consume.
Table 6.3. Good food sources of select micronutrients for athletes
| Foods rich in calcium | Foods rich in iron | Foods rich in vitamin C |
| Milk | Beef | Citrus fruit |
| Yoghurt | Lamb | Capsicum |
| Cheese | Beans | Berries |
COMBINING FOODS: MEALS FOR ACTIVE PEOPLE
Since we consume foods as part of meals and in the context of a whole diet, it is important to consider how different foods may fit together to create a healthy eating pattern for athletes and active people. Recreational athletes may focus on developing a healthy eating plan to promote good health, while highly competitive athletes may follow carefully designed eating plans to maximise performance and attain optimal body composition. There are a number of issues that should be considered when creating an eating plan for athletes.
• The amount and timing of carbohydrate and protein intake should be adjusted based on energy expenditure and sport-specific requirements (see Chapters 9 and 10 for more details).
• Fat intake should be adjusted to support appropriate energy intake and body composition goals (see Chapters 13 and 17 for more detail).
• Fibre should be avoided prior to a training session to minimise gastrointestinal disturbances (see Chapter 23 for more detail).
• Special dietary requirements and personal preferences should be considered as part of an individualised dietary plan to maximise satisfaction with and adherence to the diet.
• A variety of enjoyable flavours and textures should be used to encourage consumption.
• Food safety should be considered, especially for athletes eating on the go or travelling in foreign countries (see Chapter 21 for more detail).
• Convenience is important for busy athletes and active people juggling training, work and family commitments.
• Meal planning and time management are important skills to develop to support individuals to make time for healthy eating.
• Cooking skills may need to be taught to support athletes and active people to prepare their own healthy meals.
An example of a one-day eating plan that meets the Australian Dietary Guidelines and the Eating and Activity Guidelines for New Zealand Adults is provided in Box 6.3. This eating plan is just a starting point and may not meet all of an individual’s macronutrient or energy requirements. It may also need to be modified to meet individual athletes’ personal preferences and dietary requirements.
Table 6.4. Nutrient composition of foods commonly consumed by athletes
Source: NUTTAB 2010 (Food Standards Australia New Zealand); The University of New South Wales; Professor Heather Greenfield and co-workers at the University of New South Wales; Tables of composition of Australian Aboriginal Foods (J Brand-Miller, KW James and PMA Maggiore). There are limitations associated with food composition databases. Nutrient data published in NUTTAB 2010 may represent an average of the nutrient content of a particular sample of foods and ingredients, determined at a particular time. The nutrient composition of foods and ingredients can vary substantially between batches and brands because of a number of factors, including changes in season, changes in formulation, processing practices and ingredient source. While most of the data contained in NUTTAB 2010 are generated from analysed values, some of the data are borrowed from overseas food composition tables; supplied by the food industry; taken from food labels; imputed from similar foods; or calculated using a recipe approach.
Box 6.3: A one-day eating plan
SUPER-START BREAKFAST
200 g plain reduced fat Greek yoghurt
¼ cup rolled oats or store-bought muesli
15 g walnuts (about 6 nuts)
15 g almonds (about 10 nuts)
¼ cup frozen raspberries
1 orange
This super-start breakfast provides good serves of protein and carbohydrate, and moderate amounts of monounsaturated fats. It combines the convenience of store-bought muesli with added nuts for additional fibre, protein and monounsaturated fats. The berries and citrus fruit provide antioxidants and boost the flavour.
This provides: 1 serve milk and alternatives, 1 serve grains, 1 serve meat and alternatives, 1.5 serves fruit, 46 g CHO, 15 g fibre, 27 g protein, 29 g total fat, 5 g saturated fat, 2420 kJ.
LUNCH-TO-GO
2 slices of wholegrain bread
40 g shredded cooked chicken breast
1 tbsp avocado
2 tsp reduced fat mayonnaise
1 slice Swiss cheese
10 baby spinach leaves
½ sliced tomato
¼ sliced red capsicum
¼ sliced cucumber
⅛ sliced red onion
1 red apple
This convenient lunch on the go can be prepared the night before and refrigerated or stored in a cooler bag with an ice pack until you are ready to eat. The simple chicken sandwich gets a flavour and nutrient boost with generous serves of a variety of salad vegetables. The amount of chicken or cheese can be increased if more energy or protein is required. To save time preparing food, chop up whole vegetables and place the unneeded portions in containers in the refrigerator ready for lunch the next day.
This provides: 2 serves grains, 0.5 serves milk and alternatives, 0.5 serves meat and alternatives, 2 serves vegetables, 1 serve fruit, 54 g CHO, 13 g fibre, 50 g PRO, 17 g total fat, 6 g saturated fat, 2163 kJ.
POWER-PACKED DINNER
150 g oven baked salmon fillet + 2 tsp lemon juice
1 medium boiled potato (skin on) + 2 tsp olive oil and 2 tsp chopped fresh parsley
½ cup steamed green beans
½ cup cooked carrots
1 wholemeal dinner roll
This simple dinner can be prepared with minimal cooking skills and packs in good amounts of carbohydrate, protein and omega-3 fats. The generous serves of vegetables are ideal for a meal that is consumed at the end of the day when you have time to sit down and enjoy time with friends or family. Vary the vegetables or the type of fish to suit your tastes, and make an extra portion so you have a meal ready to reheat for dinner tomorrow night. For a more budget-friendly option, try preparing salmon patties using tinned salmon.
This provides: 1 serve grains, 1.5 serves meat and alternatives, 4 serves vegetables, 29 g CHO, 7 g fibre, 51 g PRO, 39 g total fat, 8 g saturated fat, 2862 kJ.
SIMPLE SUPPER
1 cup mixed grain breakfast cereal
1 cup skim milk
Breakfast cereal is a great staple to keep on hand for a quick snack any time of the day. Check the labels to choose one that contains wholegrains and is low in sugar.
This provides: 2 serves grains, 1 serve milk and alternatives, 59 g CHO, 4 g fibre, 15 g PRO, 1 g total fat, 0 g saturated fat, 1321 kJ.
After reading this chapter, you should understand the importance of consuming whole foods and be familiar with food selection guides. You have identified some foods that can help you meet your dietary goals, and can use the resources listed in the Australian Dietary Guidelines <https://www.eatforhealth.gov.au/> and the Sports Dietitians Australia website <https://www.sportsdietitians.com.au/factsheets/>.
Key messages
• A whole food diet provides more benefit than can be gained by consuming nutrients alone.
• The Australian and New Zealand governments have used the best available evidence to develop dietary guidelines and food selection guides to help the general population maintain good health.
• Athletes may benefit from additional individualised dietary advice from an Accredited Sports Dietitian.
• Carbohydrate-rich foods can be selected to maximise performance and minimise gastrointestinal discomfort.
• Protein can be obtained from a number of plant and animal sources to meet an athlete’s protein requirements.
• Athletes can meet all of their vitamin and mineral requirements with a whole food diet.
REFERENCES
American Society for Nutrition, 2011, Protein Complementation, <https://nutrition.org/protein-complementation/>, accessed 29 March 2018.
Food Standards Australia New Zealand, 2010, NUTTAB 2010—Australian Food Composition Tables, Canberra, ACT: Food Standards Australia New Zealand.
Ministry of Health, 2015, Eating and Activity Guidelines for New Zealand Adults, Wellington, NZ: Ministry of Health.
National Health and Medical Research Council, Australian Government Department of Health and Ageing, New Zealand Ministry of Health, 2006, Nutrient Reference Values for Australia and New Zealand, Canberra, ACT: National Health and Medical Research Council.
National Health and Medical Research Council, 2013, Australian Dietary Guidelines, Canberra, ACT: National Health and Medical Research Council.
