Diabetes mellitus, more commonly referred to as diabetes, is on the rise. It is a metabolic disorder classified by abnormally high blood sugar and low levels of the hormone insulin. When you eat something sweet your blood sugar levels rise quickly, triggering the release of insulin to help bring them back to normal.
Symptoms of diabetes occur as a result of glucose staying in the blood rather than being transported to cells to be used up as energy. The body reacts to this by flushing out as much glucose as it can in the urine. As a result, symptoms can include needing to go to the loo too often, increased thirst, fatigue, unexplained weight loss and blurred vision.
In the initial stages of diabetes symptoms can sometimes be minimal, which can make it harder to diagnose. With type 1 diabetes, you may lose a significant amount of weight for no apparent reason, when still consuming your normal intake of food. In type 2 diabetes, weight loss may also occur at onset, however individuals with type 2 diabetes are often overweight to begin with so weight loss may not be as noticeable.
People with diabetes have two to four times the risk of developing heart disease or stroke than the general population. They are also highly susceptible to conditions such as nephropathy (damage to the kidneys) and peripheral neuropathy (diabetic nerve damage). Sufferers who have chronic diabetes are about 50% likely to experience some kind of nerve damage.
Type 1 diabetes occurs when the body’s immune system destroys the insulin-producing cells (the so-called pancreatic beta cells) and without insulin production in the body, blood sugar levels remain high. There are several hypotheses as to the cause of type 1 diabetes, including viral or bacterial infection and/or an autoimmune reaction to components in food such as cow’s milk. The lack of insulin production causes the body to break down its own fat and muscle reserves for energy.
In type 2 diabetes, insulin is produced but the target cells do not recognise it and therefore glucose is not able to move from the blood into the cells. Thinking it hasn’t produced enough insulin, the body produces more; type 2 diabetes develops when the beta cells cannot meet this increased demand. A high production of insulin over a long period of time reduces the sensitivity of the cells, resulting in ‘insulin resistance’. Risk factors for type 2 diabetes include increasing age, smoking, obesity and a sedentary lifestyle (lack of physical activity), all of which affect the actions of insulin within the body.
A third type of diabetes is ‘gestational diabetes’, which occurs during pregnancy. Gestational diabetes is most likely the result of the production of high levels of a variety of hormones, which impair the action of insulin in the tissues, thereby raising blood sugar. This type of diabetes is only temporary and usually stops after giving birth.
Type 1 diabetes cannot be cured. As far as treatment is concerned, you will need insulin injections for life to help balance blood glucose levels and without this treatment, the condition is life-threatening.
For type 2 diabetes, alongside lifestyle recommendations, medication may be given to keep blood sugar levels down. Insulin may also be required for some individuals if blood sugar remains too high.
A new procedure giving hope for future treatments of type 1 diabetes includes the transplantation of healthy islet cells, taken from the pancreas of a donor. Such treatment may reduce episodes of abnormally low blood sugar episodes, however this is still in the development stages.
Exercise is key to the prevention and treatment of diabetes as it helps to increase insulin sensitivity, thereby helping glucose to leave the blood. Exercise is therefore particularly beneficial for those with type 2 diabetes and, alongside dietary intervention, can even help to reverse the disease. A sedentary lifestyle is associated with a significant increased risk of developing type 2 diabetes.
If you smoke, stop! The health risks associated with smoking are increased for someone with diabetes and the health complications associated with diabetes, such as circulatory problems in the legs, can be worsened by smoking.
Curb those carbs. Maintaining a healthy weight may be easier said than done, but being overweight is one of the biggest triggers of the disease. This is especially true for those who carry fat around their stomach and hip area. Storing fat around your middle may in part be down to your genes, but it is a combination of this genetic component and dietary factors that result in an increased risk of diabetes. If you are predisposed to easily storing fat around your middle, follow the diet tips below to help lower your risk of diabetes.
The amount of carbohydrates consumed in your diet will determine the amount of insulin required to balance blood sugar levels. Low glycaemic index (GI) carbohydrates (slow-releasing carbohydrates), will have less of an impact on blood sugar levels as the glucose they contain is released much more slowly into the blood. High GI carbohydrates, such as sugar, are released into the blood quickly and may be required temporarily if blood sugar levels are abnormally low (if, for example, too much insulin has been administered). However for everyday eating habits, it is generally easier to manage blood sugar levels with low GI carbohydrates from foods containing fibre, such as wholegrains and fruits. Choosing low GI carbohydrate options will prevent blood sugar peaks, which may help to prevent blood vessel damage caused by high blood sugar. Choosing low GI carbohydrate foods may also help to reduce fat storage around your middle, but do bear in mind that a very low carbohydrate diet may result in low blood sugar levels if any insulin administered is not reduced accordingly.
In addition to sugar, keep an eye on your fats. Healthy fats are vital for someone with diabetes as a lack of insulin, or reduced insulin activity can affect the function of enzymes required to metabolise important fatty acids in the body. As a result, individuals with diabetes have lower levels of EPA and DHA (omega-3 index) which can have a negative effect on the body’s immune system, inflammatory response and cardiovascular system. It is therefore vital to incorporate plenty of omega-3 into your diet. Excellent food sources include oily fish such as mackerel, anchovies, herring and salmon. Aim to have 1-2 portions of oily fish per week if you have diabetes.
Fish not your thing? A good quality omega-3 supplement may be the answer. There is increasing evidence that supplementing with long-chain omega-3 fatty acids has significant beneficial effects on diabetic neuropathy (damage to nerves) and serum lipids (cholesterol, triglycerides), as well as other diabetic complications such as nephropathy (damage to the kidneys) and macroangiopathy (fat and blood clots in the large blood vessels). Ideally a dose of 600-1000mg of omega-3 is needed for therapeutic effect. would be suitable to offer these beneficial effects.
Supplementing with fatty acids benefits both the cardiovascular system and the nervous system, nourishes the myelin sheath (required to protect part of the neuron) and prevents further degeneration of inter-cellular communication. It also reduces the risk of developing neuropathy, and actually reinvigorates nerve endings to overcome numbness and the likelihood of eventual tissue loss.
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