Water or fluid is a vital component of our diets, even though it’s not considered a specific nutrient.

Why do we need water?

Water makes up 50 to 70 per cent of an adult’s total body weight and, without regular top-ups, our body’s survival time is limited to a matter of days.

Water’s essential for the body’s growth and maintenance, as it’s involved in a number of processes. For example, it helps get rid of waste and regulates temperature, and it provides a medium for biological reactions to occur in the body.

Water’s lost from the body through urine and sweat, and must be replaced through the diet. If you don’t consume enough you can become dehydrated, causing symptoms such as headaches, tiredness and loss of concentration. Chronic dehydration can contribute to a number of health problems such as constipation and kidney stones.

How much do we need?

The body gets its fluid from three sources:

• Drinks, either plain water or as part of other beverages including tea, coffee and squash
• Solid foods, especially fruit and vegetables (even foods such as bread and cheese provide small amounts of fluid)
• As a by-product of chemical reactions within the body

 

Most healthy adults need between one and a half to three litres a day, so aim to drink six to eight medium glasses of fluid daily. Beverages such as tea, coffee and fruit juices count towards fluid intake, and may bring with them other nutrients or benefits.

You may require more fluid if you’re very physically active or during periods of hot weather.

You can judge whether you’re drinking enough by the colour of your urine. If it’s a pale straw colour then your fluid intake is probably fine. If your urine is dark yellow, you probably need to drink more.

Bottled water

There are two types: spring water and mineral water.

Spring water is collected directly from the spring where it rises from the ground, and must be bottled at the source. UK sources of spring water must meet certain hygiene standards, and may be further treated so they meet pollution regulations.

Mineral water emerges from under the ground, then flows over rocks before it’s collected, resulting in a higher content of various minerals. Unlike spring water, it can’t be treated except to remove grit and dirt. Different brands of spring and mineral waters have differing amounts of minerals depending on their source.

Is it necessary to buy bottled water?

The drinking water available from UK taps is perfectly adequate to replenish fluid loss, and undergoes many processes to bring it up to the standards set out in the UK Water Supply Regulations.

In some areas tap water has fluoride added, which can reduce the risk of dental decay.

There are certainly no proven health benefits of bottled water over tap water. Although there are growing concerns about the sustainability of bottled water, ultimately it comes down to personal choice.

The foods in this group are important sources of protein, vitamins and minerals, and are particularly rich in calcium, which is essential for healthy bones and teeth.

What foods are in this category?

This food group includes milk and milk products – cheese, yoghurt and fromage frais – but not butter, margarine or cream. They belong in the fat and sugar group of the Food Standards Agency’s ‘eatwell plate’.Varieties of milk

Supermarkets now stock many different varieties of milk. The most common in the UK is still cow’s milk, but others include sheep and goat’s milk, as well as a number of plant-based substitutes – including soya, rice, oat and almond milk – for those with lactose intolerance.

Milk in the UK (generally cow’s milk) is distinguishable by its fat content.

• Whole or full-fat milk contains about 3.5 per cent fat
• Semi-skimmed contains about 1.7 per cent fat
• Skimmed milk contains 0.1 to 0.3 per cent fat

 

Even whole milk is relatively low in fat and certainly semi-skimmed milk can be labelled as a low-fat food. Contrary to popular belief, lowering the fat content in milk does not affect the calcium content, so an adequate calcium intake can still be obtained from lower-fat dairy products. However, low fat milk contains less energy and lower amounts of fat soluble vitamins and isn’t suitable for children under two years.

Some supermarkets have now started selling milk with a 1 per cent fat content which has almost half the fat of semi-skimmed milk but retains a more creamy flavour. This is a good option for those people who want to lower the amount of fat they’re consuming but don’t like the taste of skimmed milk.

Milk productsCheese contains the same beneficial nutrients as milk, but most cheeses contain much more saturated fat and high levels of added salt, so it’s important to only eat full-fat cheese occasionally and in small portions.

Yoghurt is rich in protein and vitamin B2: essentially the same nutrients as in milk. Some varieties contain living bacteria that are healthy for your digestive system (probiotics). Yoghurt can be made from whole or low fat milk, but be careful. Fruit yoghurts often contain added sugar. Low fat doesn’t necessarily mean low calories. If you’re watching your weight, look for ‘diet’ versions, or make your own by mixing fruit with natural, low fat, unsweetened yoghurt. Check out the labels of packs for details.

The importance of calciumCalcium is a mineral that helps build strong bones and teeth, regulates muscle contraction (including the heartbeat) and makes sure the blood is clotting normally. Milk and dairy products have long been held as an important source of calcium, although more recently the role and safety of dairy calcium sources have been questioned by some scientists and more research is needed to draw a firm conclusion.

Other sources of calcium include:

• Fish (for example sardines)
• Dried fruit
• Sesame seeds
• Almonds
• Soya
• Dark green leafy vegetables

 

More importantly, research also suggests that calcium in your diet is less important in developing healthy bones than vitamin D (from your daily diet or from the sun’s effect on the skin). Similarly, sufficient exercise is now seen as another vital factor in maintaining healthy bone structure and density – concerns have been voiced that a lack of excercise in growing children will have a detrimental effect on their bones.

Calcium can continue strengthening your bones until the age of 20 to 25 when peak bone mass is reached. After this point, your bones can only maintain or lose their density and grow weaker as a natural part of the ageing process. Inadequate dietary calcium intake before this age can increase the risk of brittle bone disease and osteoporosis, as calcium is drawn from the bones as a reserve.

Each year in the UK, over £1.7 billion is spent on treating osteoporosis. Health professionals estimate that one in two women and one in five men over the age of 50 in the UK will break a bone, mainly because of osteoporosis. Women are more affected as they have less bone mass than men, and may lose it faster as they get older, especially after the menopause when falling oestrogen levels result in the loss of the protective effect of oestrogen on bone density.Why children need calcium

Calcium is an essential nutrient for all children to help grow strong bones and reduce the risk of developing osteoporosis when they’re older. But many children and teenagers don’t receive their recommended daily intake. Encouraging children and adolescents to drink more milk, rather than other drinks, can provide not only calcium, but also important proteins, carbohydrates and micronutrients.

Fruit and vegetables are low in energy and packed with vitamins, minerals, protective plant compounds and fibre, so they’re a great source of nutrients and vital for a healthy diet.

Five a day

Due to their nutritional and health benefits, it’s recommended that fruit and vegetables form the basis of your diet, with a minimum intake of five portions each day – about a third of your daily food consumption. Currently the UK averages two to three portions a day, so we’re falling well short of the benefits they can provide.

Fruit and vegetables should be incorporated into every meal, as well as being the first choice for a snack. Population studies have shown that people who eat a lot of fruit and vegetables may have a lower risk of chronic disease, such as heart disease and some cancers. Health benefits can be gained from fresh, tinned (in natural juice), frozen, cooked, juiced or dried versions. Potatoes don’t count though, as they’re a starchy food.

How much is a portion?

• One piece of medium-sized fruit, such as an apple, peach, banana or orange
• One slice of fruit, such as melon, mango or pineapple
• One handful of grapes or two handfuls of cherries or berry fruits
• One tablespoon of dried fruit
• A glass (roughly 100ml) of fruit or vegetable juice
• A small tin (roughly 200g) of fruit
• 3 tablespoons of fruit salad or stewed fruit
• A side salad
• A serving (roughly 80g) of vegetables, such as frozen or mushy peas, boiled carrots or stir-fried broccoli
• Cooked dishes that contain significant amounts of vegetables may also count

 

So how do you ensure an intake of five portions a day? Here’s a typical plan:

• Glass of fresh orange juice or smoothie for breakfast = one portion
• Small pack of dried apricots for mid-morning snack = one portion
• Side salad with lunch = one portion
• Sugar snap peas and broccoli, served with main meal = one portion
• Strawberries as dessert = one portion

 

Do remember that some fruits contain many of their nutrients just under the skin, so eating them with the skin on can provide greater nutritional benefits and the maximum amount of fibre compared with just drinking the juice of the same fruit.