The more knowledge you have about different types of food and the effect they have on your blood glucose and weight, the more control you will have over your diabetes. There are three basic nutrients that make up the majority of our food intake. These "macronutrients" are carbohydrate, fat and protein.
Carbohydrate
The food group that will have the biggest impact on your diabetes is carbohydrate, because it affects both your blood glucose levels and your weight. Carbohydrates are our primary source of energy and can be divided into two groups: Sugar and starch (sometimes referred to as "complex carbohydrates"). Sugar comes in different forms, including sucrose (refined sugar), fructose (found in fruit) and lactose (found in milk). It is important to limit the amount of sugar you eat particularly between meals because it can cause rapid rises to your blood glucose level. Eating lots of sugar can also contribute to weight gain.
Complex carbohydrates are more fibrous, starchy foods such as bread, potatoes, rice and pasta. The body has to break down these foods into simple sugars before they can be absorbed into the blood stream. This creates a slower, steadier release of sugar into the blood. The more fibre the carbohydrate contains, the longer it will take your body to absorb the food. For example, the starch in vegetables is broken down more slowly than the starch in bread. High fibre foods are also better for satisfying your appetite. You will feel full for longer after eating wholemeal bread (which is high in fibre) than white bread (which is lower in fibre).
Fat
If you have diabetes, a key goal for weight control should be to decrease your fat intake. This will help reduce your risk of artery and heart disease. You should be particularly careful about saturated fats. Foods that contain large amounts of fat include dairy products and red meat. Saturated fat is also found in snack foods such as chocolate, cakes and most crisps. Check the nutritional information on your food packaging, with the view to replacing saturated fats with monounsaturated and polyunsaturated fats, wherever possible.
Protein
In people who don't have diabetes protein won't increase blood glucose levels. However, people with diabetes should be aware that proteins stimulate the release of glucagon, which in turn helps to convert protein into glucose (a process called gluconeogenesis). Contrary to popular belief, protein does not slow the absorption of carbohydrate, and adding protein to a carbohydrate snack does not prevent hypoglycaemia. High protein foods can make you feel full, which will be an advantage if you are watching your weight. Meat and fish have a high protein content but can also be high in fat, so try to choose lean cuts of meat.
Your dietician will be able to explain more about the impact of different foods on your blood glucose levels and weight. There are also some basic rules of thumb that you can follow to ensure you are eating sensibly.