The Science Behind Sugar

The Science Behind Sugar

       The first step to understanding sugars is to understand the various terms used to describe them, as they don’t all mean the same thing. The best way to go about this is to acknowledge that carbohydrates are all made up sugar molecules. Sugar molecules are the building blocks of carbs. The smallest sugar molecules that you need to be aware of are “glucose” “fructose” and “galactose”. These make up most of the carbs we eat on a daily basis. For example:

  • Paring glucose to fructose gives us sucrose: classic white table- sugar, also found in honey and corn syrup
  • Paring glucose to galactose gives us lactose, the carb found in milk- products.
  • Lining up long chain webs of glucose gives us starch, the carb found in grains, wheats, legumes, potatoes and vegetables.

How Does Your Body Process Sugar?

       Carbohydrates are broken down by the gut into the smaller sugar molecules “glucose”, “fructose” and “galactose”, so that they can be absorbed into our bloodstream. The pancreas then releases the hormone insulin into your bloodstream to get sugar into our cells to use as energy. If you eat more calories than your body is burning, the sugar will be stored in your liver, muscles and even as fat tissue. If you burn more calories than you eat, the pancreas releases another hormone, glucagon, which helps release the stored sugar and fat to the blood so that it can then be used by our cells for energy. So it is excess calories, and not sugar by itself, that ultimately decides if you gain or lose weight!

What Happens if You Over-Eat?

       Assuming you eat more calories than you burn, you will gain weight. If your diet is also high in sugars, more fat may be stored between your inner organs (called “visceral fat”). Combined with low levels of exercise, the fat between your organs can make your pancreas stop working properly, leading to insulin levels not adjusting accordingly (called lowered insulin sensitivity). Your pancreas may eventually even produce less insulin! Lower insulin sensitivity means your body cannot get sugar from the blood into your cells where it is needed, leading to higher blood sugar levels. This is what we call Diabetes.

       Over time, high blood sugar levels will make your arteries, liver and metabolism dysfunctional and lead to heart disease, vision impairment, kidney dysfunction, nerve dysfunction and much more. As doctors we see these patients every day, and lifestyle change is the first line of treatment! You can therefore see why you have more reasons than looking good on the beach to keep your weight balanced.

Which Sugars Are Dangerous?

           What you may also have noticed from the list above is that the same sugar molecule that you get in white sugar is found naturally in fruits and vegetables. Thus, on a molecular level, there is no real difference between “added sugars” and “natural sugars”. So what makes added sugars dangerous? It's the amount one consumes. Too much sugar is linked to heart disease, even when considering calories consumed!

How to Hit the Sugar Sweet Spot

       Studies show that safe sugar consumption is below 10% of calories, but at the same time data shows that we are getting 15 - 21% of our calories from sugar! In some cases, many American's consume 3x the daily recommended amount of sugar. 

      So why are we over consuming sugar? Because it is being ADDED to many foods in the form of added sugars! About 75% of items in the average American grocery store contains added sugar. So, even though there is nothing inherently dangerous in added sugars, we still recommend cutting them out of your diet to hit the sugar sweet spot, minimizing your risk of heart disease!

“Cutting out added sugars is thus a good principle to follow to reach the sugar sweet spot.”

Sugar itself isn’t poisonous, but getting too much of it may not be optimal to your health.

Think Bigger Than Just Sugar

       But what if you manage to stay around the 10% mark, and choose to get these 10% from added sugars instead of natural sugars – are they the same thing? Well, yes and no. Even though doing this might make you stay “safe” when it comes to sugar itself, you are compromising other micronutrients that are essential for you health. Getting 10% of your sugars from ice cream and candy will most likely mean that you are missing out on other micronutrients that you need at the end of the day. This is especially true if you are trying to lose weight, since you are eating so little food already.

         Naturally occurring sugars are a packaged deal, so when you get sugar from a whole fruit or vegetable, you almost always get vitamins, minerals, fibers, complex carbohydrates and possibly fat. This is why it's healthier to have whole fruits than just added sugar, even if the sugar amounts are equal between the two. Also, the “packaged deal” makes whole food sugar sources hard to over consume and allow you to stay within healthy doses of sugar.

Article by Artin Entezarjou, M.D. from EBT – Evidence Based Training. 

Making fitness science simple and applicable

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