Chapter 1

Everyone needs an adequate supply of energy for the body to function normally, for growth and replacement of tissue as well as any physical activity. If your weight is to be stable over time, your energy levels must be in balance, that is:

If you eat more energy than your body needs, your body stores this extra energy as fat and you become overweight. If you eat less energy, your body will start to use up its reserves and you will lose weight. This happens, for example, if you ‘go on a (weight-reducing) diet’. The change in weight will be due to loss of both muscle and fat. However, your aim is to lose any excess fat stores without losing any muscle. Raising activity levels can help to bring your energy levels back into balance, reduce fat stores and build up muscle stores. In other words, being more active will help to get rid of the flab and make you fitter and stronger.

Having kidney disease does not, in itself, change the amount of energy you need. This depends on your individual body function and make-up, how active you are, as well as on whether you have any other medical conditions.

It may be that you are overweight (see Chapter 10). If this is the case, your health is likely to be improved by losing some weight. This will reduce your risk of heart disease and cancer, and help to prevent and control conditions such as diabetes and high blood pressure. It is wise for anyone with a medical condition to check with their doctor before trying to lose weight (see Chapter 10, pages 42–48, for more information on weight control).

On the other hand, people sometimes find that it becomes more difficult to eat enough energy, perhaps because they have lost their appetite. This can be for a number of reasons, from anxiety to a worsening medical condition. Reduced energy intake can lead to ill health, muscle loss and nutritional deficiencies. If you feel that you are having trouble eating enough, or are losing weight without meaning to, you should ask to see a dietitian.

The energy we get from food is measured in kilocalories (usually referred to simply as ‘calories’), and varies depending on the different nutrients that the food contains (see the box below). Be aware that alcohol also contains calories.

Fat	9 (kilo) calories per gram
Carbohydrate (sugar and starches)	4 (kilo) calories per gram
Protein	4 (kilo) calories per gram
Alcohol	7 (kilo) calories per gram

Fat is the most concentrated form of energy or calories. Weight for weight, it has over twice the energy of carbohydrates or protein. It is important to know this if you need to gain or lose weight. This is the theory behind low-fat diets; they cut out fat and use reduced-fat products to lower the total number of calories you eat. Eating fewer fatty foods, such as butter, margarine, oil or full-fat products such as full-cream milk and replacing them with skimmed milk, low-fat and diet yoghurts, can help. Other examples of fatty foods to reduce include cream, pastry and fried foods. The type of fat that you eat has an influence on your risk of heart disease. The better choices are the unsaturated fats and oils, such as rapeseed (often sold as ‘vegetable’ oil) and olive oils and margarines. These should replace the saturated fats, such as ghee, butter, palm oil or lard.

If you are underweight, or have a poor appetite and are unable to increase the amount of food you can eat, you may want your diet to be richer in energy. In this case you can include fatty foods in your diet but where possible try to choose the unsaturated types of fat to increase in your diet. For more information about fats, see Chapter 4.

Some examples of starchy and sugary foods

Starchy foods	Sugars/sugary foods
Bread	Sucrose
Potato	Glucose
Rice	Fructose
Pasta	White sugar
Noodles	Brown sugar
Yam	Demerara sugar
Breakfast cereals (plain)	Honey
Plantain	Maltodextrins
Chapatti	Molasses
Polenta	Jam, jelly, marmalade
Couscous	Sweets (boiled, chews, mints, etc.)
Oats	Turkish delight
	Full sugar fizzy drinks and squash

There are two types of carbohydrates, starches and sugars (see the table above). As well as being a good source of energy, starchy foods can be naturally low in fat and provide many essential nutrients such as B vitamins and some protein. Wholegrain varieties also provide fibre to prevent constipation and tend to be more filling. Sugar, however, is found mainly in processed foods such as sweets, cakes and fizzy drinks, which don’t have many other nutrients. Eating too many sugary foods and snacks can lead to health problems including overweight and tooth decay.

Generally, the recommendation is to take most of your energy in the form of high-fibre, starchy foods such as wholemeal bread and pasta, brown rice and wholegrain cereals. It is also beneficial to eat less sugary foods, especially if you are trying to lose weight. Ways to reduce your sugar intake can be seen in the table opposite.

People who need to put on weight are sometimes advised to include some sugary foods, such as biscuits or desserts, because they tend to be high in calories and not very filling. Check with your doctor or dietitian if you feel this applies to you, especially if you have diabetes.

Foods high and low in sugar

Higher sugar choices	Lower sugar choices
Standard squashes and fizzy drinks	Diet, low-calorie, ’sugar-free’, ‘no added sugar’ drinks/squashes/fizzy drinks
Sucrose	Choose artificial sweeteners
Add sugar/jam/honey/syrup to foods and drinks	e.g. Canderel/Hermesetas/Sweetex or shop’s own brand of saccharin-based or aspartame-based sweetener for desserts and drinks
Standard yoghurts (Note: low-fat yoghurts may still be high in sugar)	Diet or ‘lite’ yoghurts
Fruit tinned in syrup	Fruit tinned in fruit juice (Note: these may need to be drained if you are on a low-potassium diet)
Standard milk puddings and desserts	Reduced-sugar desserts
Sugar-coated or cream-filled biscuits	Plain biscuits e.g. rich tea or wholemeal biscuits
Sugar-coated breakfast cereals	Plain cereals e.g. Weetabix, Shredded Wheat, cornflakes, porridge

Carbohydrate-rich foods can also be categorised by their glycaemic index (GI). This measures the rate at which they are broken down to produce glucose (the sugar found in blood). Foods, such as wholegrain breads and cereals, oats, pulses and pasta, have a lower GI and cause a more gradual rise in blood glucose. This is preferable to the rapid rise (and fall) in blood sugar caused by high glycaemic foods such as sweet drinks, white bread and sugary breakfast cereals.

It can help to choose a lower GI food instead of its higher GI equivalent as long as you are sticking to healthy eating guidelines. Think about GI as a positive message to include more wholegrain cereals and bread, pasta, noodles, pulses and oats as well as fruit and vegetables. All fruits and vegetables have health benefits regardless of their GI rating. Some foods with a higher GI can still be included in a healthy diet. Examples might include white bread, pumpkin or unsalted rice crackers.

Mixing low GI foods into a higher GI dish can reduce the overall GI of the meal; for example, you could add lentils to the minced meat mixture in a shepherd’s pie. Some of the recipes in this book have been chosen to show you how easy it is to include some healthy lower GI foods within your diet.

Some healthy lower GI foods

•Oat cereals, e.g. porridge, muesli (no added sugar)

•Granary/multigrain bread, pitta bread, ryebread

•Pasta, noodles, basmati rice, long grain white rice, bulgar wheat, pearl barley, semolina

•Yam, cassava, sweet potato, new potatoes

•Peas, dahls, lentils, most beans including chickpeas and baked beans (choose low-salt variety)

•Apples, oranges, pears, peaches, strawberries