Many of us know that eating too much sugar wrecks havoc with our health, but what many don’t yet realise is that carbohydrates whether they are in the form of fruit, table sugar, bread or potatoes all eventually break down to sugar in the body.
All sugar causes a spike in insulin and blood sugar; one of the contributing factors to diabetes, oxidative damage and inflammation. For decades we have been told to follow a high carbohydrate low fat diet, however recent research has shown that this way of eating actually increases the risk of both heart disease and diabetes.
Sugar and General Health
- Sugar is high GI and GL leading to surges in insulin which stimulates the body to manufacture fat and at the same time stalls the fat burning abilities.
- Fructose is actually no better, it has been shown to impair the body’s ability to handle sugar and reduces the effectiveness of insulin the onset to type II diabetes.
- Sugar consumption can play havoc with energy levels, creating energy dips during the day, followed by cravings for more sugar.
- Sugar suppresses the immune system and reduces our resistance to infections.
- Sugar can deplete the body of key nutrients (chromium and copper) and reduce the absorption of calcium and magnesium.
- Sugar can reduce the effectiveness of insulin in the body increasing the risk of elevated insulin levels and type 2 diabetes.
- Sugar can lead to dental decay
BODY FAT AND OBESITY
As mentioned above, consumption of carbohydrates (in particular refined carbohydrates) increases both blood glucose and insulin levels. Insulin helps the glucose enter the body’s cells. Fat is stored in our bodies in the form of triglycerides (3 fatty acids and 1 glycerol molecule), fatty acids are absorbed from the blood stream to make fat cells and are converted to triglycerides (fats in the blood), this conversion is controlled by the levels of another substance called alpha glycerol phosphate – now here is the trigger, this substance is produced when glucose is metabolised in the cell with the help of insulin. Therefore the more glucose that gets into the cells the more fat cells will be produced and ultimately converted to triglycerides.
Insulin also inhibits the production of an enzyme called lipase which is responsible for fat metabolism.
Following a carbohydrate rich meal (pasta, jacket potato, fruit salad, sweets) the level of glucose in the blood stream rises rapidly as demonstrated below (in opposition to fats which does not raise blood glucose levels or insulin).
High blood glucose levels are dangerous, the more glucose that enters the bloodstream the more the pancreas produces and releases insulin to support the uptake of this glucose into the cells, here some of it is converted to glycogen which is stored in the liver and muscles and used for energy, the remainder is stored as body fat.
Following this as seen in the graph, the levels of glucose in the blood then rapidly drops below normal, causing hunger pangs leading to snacking normally on more carbohydrate rich foods–this is casually known as the blood sugar rollercoaster, something that is very common in modern day western dietary habits.
In the short term this leads to an increase in body weight and fat. Over time this roller coaster then leads to what is known as insulin resistance as the cells have started to reject the constant flow of insulin into the blood stream. Modern day medicine refers to this as type 2 diabetes when the cells are not as sensitive and begin to resist the insulin.
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