Managing gestational and type 2 diabetes
What is Diabetes?
Diabetes is a disease state characterised by poor blood sugar control. The level of glucose in the blood should remain between 4.0 - 6.0 mmol/L outside of meal times, and ideally below 7.8mmol/L after meals. Blood glucose outside these ranges can cause problems.
If your blood sugar is too low:
Your brain and kidneys are partly dependent on a steady supply of blood glucose to keep functioning properly. That is why many people experience post meal lulls in energy. Their brains are struggling due to lack of usable energy in the form of glucose. Other brain related symptoms of low blood glucose include irritability and hunger.
If your blood sugar is too high:
High blood sugar is dangerous. Some of the cells that form the wall of your blood capillaries end up absorbing too much glucose. This damages them, causing your capillaries to become leaky. It is this that is responsible for the main problems associated with diabetes: retinopathy – blood vessels spreading over the back of the eye, nephropathy – leaky blood vessels in the kidneys and neuropathy – nerves damaged due to lack of oxygen delivery from damaged blood vessels. Initially affecting the hands and feet.
There are different types of disease:
A) Type 1 diabetes (Insulin dependant diabetes mellitus - IDDM) features destruction of the insulin secreting beta cells in the pancreas. If you have no insulin you cannot remove sugar from the blood, as insulin is one of the key ways in which glucose leaves the bloodstream and enters our tissues.
B) Type 2 diabetes involves a lack of response from our tissues to insulin. We then need more insulin to bring our blood sugar levels into a healthy range. This puts more demands on our pancreas.
C) Gestational diabetes is diabetes that develops during pregnancy and then normally goes after pregnancy is complete. There is some evidence that it is caused during the last 3 months of pregnancy by the placenta releasing a hormone that inhibits the action of insulin.
To manage diabetes it is important to adopt a diet and lifestyle that minimises high levels of blood sugar. This is in essence a low GI diet coupled with carefully timed exercise.
Virtually everybody with diabetes will discover if they monitor their blood glucose levels that a meal containing a generous portion of starchy carbohydrates will raise blood glucose significantly. Shamefully the NHS and Diabetes UK still do not recognise the importance of this fact.
Carbohydrates are the main food group that raise blood sugar. It is important to reduce significantly the amount of starchy carbohydrates such as bread, pasta, rice, breakfast cereals and potato. In some cases this may require the elimination of these foods from the diet altogether.
These carbohydrates can be replaced either with protein, fats or vegetables containing carbohydrate that do not raise blood sugar levels. These types of carbohydrates contain plenty of soluble fibre that slows absorption of the glucose, and reduces blood sugar peaks.
What if I’m pregnant or exercising?
There are two important cases where need for carbohydrate increases.
During pregnancy the baby requires mostly fat and carbohydrate. These provide it the energy it needs to grow. Protein provides material for infant growth, but baby is a lot smaller than you, and so not much is needed on top of protein that you normally consume.
You will need to extra carbohydrate from vegetables containing soluble fibre that provide glucose more slowly. Combine these foods with proteins and fats to further control the blood sugar rise. Foods such as cheese, yoghurt, coconut milk (all should be full fat), meat and fish will all help.
Many people find that they are not so sensitive to insulin in the morning. If this is the case your breakfast really needs to be low GI and a bit of post breakfast exercise such as walking, cycling or gardening could be in order.
If you exercise regularly, and especially if exercise is vigorous you will find that your blood sugar levels are much better controlled. Basically your tolerance to carbohydrates improves as your body becomes better at removing glucose from the blood.
If you time your meals so that carbohydrate is consumed within 30-90 minutes after exercise you will find that the effect on your blood sugar levels will be much reduced.
Which are the carbohydrates I can eat?
- Most vegetables apart from potato are OK. Beans, peas, all green leafy vegetables, parsnips, celeriac, courgette and all salad vegetables should be fine.
- Fruits such as apples, pears and plums should be fine. The riper a fruit the more problematic it will be. So an unripe green or yellow banana is fine, a spotty banana is dodgy.
- Porridge oats are the only breakfast cereal that is low GI. Other good breakfast options include omelette or a fry up.
- Cooked lentils are another option either as soup or a side dish.
What should I avoid?
- Bread, toast, pasta, rice, breakfast cereals from boxes, cakes and potatoes.
- All processed foods unless you are confident you can understand the blood sugar effect of all the ingredients listed on the food label.
- Shop bought sauces such as chilli sauce and salad cream.
- All fruit juices, cordials and fizzy drinks unless you water them down with at least the same amount of water.
- All flavoured yoghurts (20% sugar).