Carbohydrates
Carbohydrates are an ideal source of energy for the body. This is because they can be converted more readily into glucose, the form of sugar that's transported and used by the body, than proteins or fats can.
Even so, a diet too high in carbohydrates can upset the delicate balance of your body's blood sugar level, resulting in fluctuations in energy and mood which leave you feeling irritated and tired.
It is better to balance your intake of carbohydrates with protein, a little fat and fibre.
There are two types of carbohydrate: complex and simple.
The difference between complex and simple carbohydrates
All carbohydrates form glucose when digested. Glucose is transported around the body via blood and taken into cells to be converted into energy.
The pancreas gland in your abdomen secretes the hormone insulin, which controls the uptake of glucose by your cells.If you have any excess glucose, this is converted into glycogen – which is stored in the liver or in fat around the body.
When your body needs more energy, a second hormone called glucagon is secreted by the pancreas. This converts the glycogen back into glucose, which is then released into your bloodstream for your cells to use.
This means the body's glucose (sugar) metabolism is a cycle of glucose, insulin and glucagon reactions.The slower the release of glucose and hormones, the more stable and sustainable the energy levels of the body.The more refined the carbohydrate, the faster the glucose is released into your blood. This can cause peaks and drops in your blood sugar level and less stable energy levels in the body.
Complex carbohydrates provide a slower and more sustained release of energy than simple carbohydrates.In their natural form they contribute to long-term good health, appetite control and sustained energy levels.
How much do I need?
Current advice is that we should get half our energy needs from carbohydrates, with at least one third of our daily intake of food being starchy carbohydrates.
According to the British Nutrition Foundation, the average adult's daily diet meets this target with women getting 47.7 per cent of their daily energy from carbs (203g) and men 48.5 per cent (275g).
But not all carbohydrates are equal: refined sugars should make up only 11 per cent of your daily diet. For adults, the average intake of refined sugars is slightly higher than this recommended level, with men the worst offenders at 13.6 per cent.
The average child's intake is 16 per cent, with the main culprits being fizzy drinks and confectionery.
Do carbohydrates make you fat?
Eating too much will lead to weight gain, regardless of what foods you get your energy from. Yet while low carb diets have had much publicity, gram for gram carbohydrates contain less calories than fat, protein and alcohol.
Sugar and starch are found in both healthy and 'unhealthy' foods, so the type of carbohydrates you eat is important for your wellbeing. Many foods high in sugar (cakes, pastries, chocolate) are also high in fat or prepared with fat (chips, roast potatoes, sandwiches). Starchy foods, such as wholegrain bread, pasta etc, are rich in fibre, which is essential for digestive health and helps control appetite so you don't feel hungry
Source: http://www.netdoctor.co.uk/focus/nutrition/facts/lifestylemanagement/carbohydrates.htm