The human body needs carbohydrates (also known as sugar) to stay healthy, this is a fact. We have evolved to naturally crave high sugar food as a survival mechanism; our early ancestors depended on sugar-rich fruits to not only give them an immediate energy supply, but to also assist in fat storage so they could continue to have an energy source when food was scarce.
This craving for sugar that was once depended on for survival, is now playing a key role in rising levels of obesity, type II diabetes and cardiovascular disease, not to mention dozens of smaller ailments involving kidneys, joints, skin and more. This is because the amount of sugar we consume has increased so drastically that our bodies are no longer equipped to process it. To give you some numbers:
This is a huge growth that translates to major stress on our bodies and their abilities to function properly, and we need our bodies to function properly in order for us to fight off disease and illness (like cancer!).
There are many types of sugars and alternative sweeteners that we have developed over the years, but here I want to focus on the ones found most often in our food: glucose and fructose. These two molecules are the base of most of the sugars we use, particularly in processed foods. All carbohydrates break down into sugar in the body, that includes all grains and grain products (breads, pasta, rice, oatmeal, etc.). This is not to say that all carbohydrates are bad, as mentioned before, we need them to maintain a healthy lifestyle. This is just to emphasize that all carbohydrates, whether from grains, fruits, starchy vegetables, milk or processed sugars, break down into simple sugars (glucose, fructose, & lactose) in the body.
Glucose molecules are absorbed through the small intestine directly into the bloodstream. From there the glucose molecules attach to insulin molecules and after a small portion is stored in muscles and the liver immediate use, the rest is transported into all of a body’s cells (all cells require glucose). This presence of glucose in the bloodstream is what determines our blood sugar level. If it is too high or low, our body cannot function; therefore we have insulin to regulate that level. Unfortunately insulin is only equipped to deal with a certain level of glucose, and the amount of sugar we consume on a daily basis tends to be beyond what insulin can handle. When insulin is triggered too often by the presence of sugar, it either responds less accurately or stops responding all together. This means we have high blood sugar, and no way for that sugar to get disbursed to its proper organs and cells, a problem that then causes type II diabetes (insulin resistant diabetes).
Another important interaction is when glucose gets transported to our cells, because although our cells require glucose, the amount they require to function is very minimal. When we consume more sugar than we need, the body has no immediate use for it, so our cells will store it as fat for future use. However, we rarely will need to use those fat stores for energy because we continue to consume sugar and the process starts all over again. Human cells have an amazing ability to store as much fat as we can give them, the cell walls will just keep expanding as long as they need to. Unfortunately, once sugars are turned into fat, it becomes very difficult to get rid of them again since those are the last stores of energy your body will try to use. It usually requires a long, high-intensity workout to use up all the sugar stored in your liver and muscles and to then tap into those fat stores.
This cycle of insulin release and fat storage only happens when we eat carbohydrates, not when we eat protein or fat. In fact, when we consume carbs with protein, fat and/or fiber, it actually slows down the rate at which glucose is converted to blood sugar. This is why naturally occurring sugars in fruits and vegetables are better than processed sugars, because they come with built in fiber supplies, as well as vitamins and minerals.
The other most common form of sugar is fructose. Where glucose can be metabolized by insulin from the pancreas, fructose can only be metabolized by the liver. The problem with this is the liver is a busy organ and gets overwhelmed when too much fructose is present. If it can’t properly process the amount of sugar ingested, globules of fat will begin to grow within the liver and can eventually cause non-alcoholic fatty liver disease and cirrhosis. When your pancreas and liver are in overdrive, the stress causes the whole body to become inflamed and not function properly.
Fructose is found naturally in fruit, but with fruit you are also consuming fiber, as well as various vitamins and minerals. The fiber will slow down the metabolizing of sugar so that it is at a level the liver can handle, and the vitamins and minerals are beneficial for your overall health. Keep in mind this is good when fruit is consumed in moderation. Too much fruit consumption will still negatively affect the liver. Dried fruit is a slippery slope because without the bound water found in fresh fruit, it is easier to consume large amounts of it. For example, if you are eating fresh apricots, you may eat one or two, but with dried apricots you may eat eight or ten in a sitting. That is a lot of sugar with none of that bound water that is beneficial for digesting the sugar. The USDA recommends eating 2-3 servings of fresh fruit a day.
Sucrose (table sugar) and High Fructose Corn Syrup (HFCS)
Although glucose and fructose have varied properties and are metabolized differently, they are most often found together in sugars & sweeteners. What makes these sweeteners different is the amount of glucose vs. fructose found in each one. The chart below shows a basic breakdown of how much each molecule is found in our most commonly used sweeteners. Notice that sucrose (table sugar, what we are most familiar with), honey, and HFCS are all very similar in molecular make up, meaning our bodies process them in similar ways.
Just to be clear, the 50/50 ratio of glucose/fructose in table sugar also goes for cane sugar, raw cane sugar, powdered sugar and brown sugar, so simply trading out the amount of ‘high fructose corn syrup’ or ‘sugar’ in our grocery cart with the same amount of ‘raw cane sugar’ or ‘honey’ is not going to greatly alter the effects of our sugar intake. The overall consumption of all sugars and sweeteners should be lowered, and although I personally believe honey and raw cane sugar to be better choices based on their lack of processing, that doesn’t mean it is healthy to eat large amounts of them. Sugars off all kinds should be eaten in limited moderation.
My FD name is Kitchen Ninja (Kinja). I am from Auburn, AL. I graduated from Johnson & Wales University with a Bachelors in Culinary Nutrition. I am currently Sous Chef at Linger in Denver. My passion is creating nutritious food for others and spreading knowledge of health through food and cooking.