Tuesday, 12 May 2009
Does sugar make us fat?
Sugars are simple carbohydrates composed of a single sugar (ie. glucose, fructose) or 2 sugars together (table sugar, sucrose, is made of glucose linked to fructose).
In comparison, starch is a complex carbohydrate- made of lots of glucose molecules linked together in very long chains.
The long chains can't be absorbed by the intestine but have to be broken down to single units of glucose to be useable. Simple carbohydrates, though, are readily useable. But do they make us fat?
We know that a calorie is a calorie. Excess calories from sugar will lead to weight gain, just like extra calories from protein or fat. However, when you eat too much glucose at a time, the body can't handle it. What happens is that your pancreas makes too much insulin. Insulin is supposed to take the glucose and put it in your body tissues so it can be used. When there's too much insulin though, it grabs all your available glucose, including the little bit that's supposed to stay in your blood. The result is that your blood sugar drops and you feel hungry. You then eat more and those extra calories will lead to weight gain.
Moreover, your muscles cells start to resist taking in the excess glucose resulting in that excess getting stored as fat.
So yes. Eating too much simple sugars does put you at risk for weight gain.
Fibre slows down the absorption of glucose which is why a high fibre diet- a diet rich in vegetables, fruit and whole grains- prevents heath problems.
The Glycemic Index ranks foods according to how quickly they break down to glucose. Click here to read more about Glycemic Index from a previous blog entry.
In general, highly processed starchy foods- crackers, pretzels, cookies- and sugary foods- sodas, candies, desserts, sugary cereals- have no fiber and will cause havoc for your metabolism, providing a huge influx of glucose.
How much sugar is too much sugar?
Per day, it's recommended that less than 10% of your total calories come from added sugars (this doesn't include sugar found naturally in fruits and plain milk). In a 2000 calorie diet, that means you should be aiming for less than 50 grams (about 10 teaspoons) of added sugar a day. The average American eats double that a day.
Sweet tips to limiting your sugar intake
Avoid or cut back on non-diet soft drinks. A 12 oz can of Coke has practically your daily limit of added sugars, 40 grams!!
Watch out for fruit 'drinks', 'beverages', and 'cocktails'- they contain very little real fruit juice and a lot of sugar.
Limit candy, cookies, cakes, pies, doughnuts, granola bars, pastries and other sweet baked goods- eat fruit instead. Desserts in restaurants, with their huge portion sizes, have a large amount of added sugar. A medium chocolate milkshake at McDonald's has a whopping 111g sugar!
Remember that 'fat-free' does not mean 'sugar-free' or 'calorie-free' .
Look for breakfast cereals with less than 10 grams (ideally less than 8 grams) of sugar per serving- read the label!
I found this cool site, sugarstacks.com , that shows us how much sugar there are in some foods. Pretty eye-opening!
They use sugar cubes- 1 cube is equivalent to 1tsp or 4grams.