Glycemic Index Shows Not All Carbs Are Created Equal

This recent widespread carbohydrate awareness has brought a key fact into
the spotlight: Not all carbs are created equal.

Carbohydrates, if you still aren't sure, are foods that are broken
down/absorbed/metabolized into sugar when ingested. These foods include
bread, fruit and sugar. The difference between one carb and another? Some
carbohydrates provide your body with a slow, steady stream of fuel, while
others enter your bloodstream quickly, providing you with short bursts of
energy.

The absorption rate of carbs is measured by something called the Glycemic
Index (GI), a ranking system that assigns a number between one and 100 to a
food based on how fast it is absorbed into your system -- in other words,
how fast it raises your blood sugar levels.

If the carbs in a food are metabolized quickly, the GI is high, usually
above 70. Carbs such as Corn Flakes, mashed potatoes and apple juice have
GIs over 70. On the other hand, if your body has to unravel a carb, so to
speak, before the sugar in that food makes its way into your blood, that
food's GI is low, usually less than 55.

Fibre, protein and fat are layers that lower the carb-absorption of a food.
For example, many beans and lentils, as well as slow-cooked oatmeal, have a
low GI. That's because the fibre in those foods slows the absorption of
sugar into the blood.

On the same note, adding a slice of cheese (high in fat) or a tablespoon of
peanut butter (high in protein) to a piece of toast suddenly lowers its GI.

The lesson here is that it's not necessarily the amount of carbs you're
eating that matters. Rather, it's the type of carb you choose. And what you
eat your carbs with.

The questions is: How do you know what carbs to choose, and when?

That depends on the circumstances. Here's how you know: BEFORE YOU
EXERCISE: Stay low, say many experts. Studies have shown that eating low-GI
foods about two hours before working out help maintain steady blood-sugars
during exercise. Fruit, yogurt (it contains the sugar, lactose, found in
milk) and oatmeal may help keep you going in the long run. If you have no
choice but to fuel up just minutes before an intense workout, load up on
carbs that enter your blood faster, such as an energy bar or a sports drink.

DURING EXERCISE: If you're going hard and heavy -- for example during a
marathon or a road race -- go for high-GI foods that fuel your muscles and
keep you feeling alert. Again, reach for the sports drinks or dextrose gels.

AFTER INTENSE EXERCISE: Most experts say high GI foods are essential when
you're trying to restock your energy stores and refuel your muscles.

Of course, there are reasons to stick with low-GI foods. The theory behind
cutting carbs: When you eat a high GI food, your blood sugar levels soar,
triggering the release of insulin, a hormone that lowers blood sugars (and
promotes the storage of fat). Repeated spikes in blood sugar levels, the
theory goes, takes its toll on health, causing weight gain, hormone
imbalances and the narrowing of blood vessels.

The bottom line: Eliminating carbs is unnecessary -- and possibly
unhealthy. Instead, choose your carbohydrates wisely, sticking mostly to
low-GI carbs.