As we become more aware of the contribution of sugar to our hefty waistlines, we face hundreds of complicated food choices each day. We are also bombarded with messages from others who tell us that all calories are equal and it doesn’t matter which type of sugar you get your calories from. If you eat too much sugar, easy to do in this day of processed foods with corn derivatives added to everything from ‘artificial’ sweeteners to beef jerky, there is some truth to this claim. Too much sugar of any kind will cause you to gain weight, fuel inflammation, damage cells through oxidation and lead to diabetes and heart disease and more. The reasons for focusing on sugar intake are compelling.
The two primary forms of dietary sugar are fructose and glucose. Fructose comes from fruit and is often added to foods in the form of high fructose corn syrup. Glucose naturally comes from a variety of vegetables and fruits and is also added to processed foods. The body, and the brain, treat these two variants of sugar quite differently. Glucose is metabolized by insulin, which is excreted by the pancreas. Too much sugar spikes insulin levels and the body stores the excess insulin as fat. Over time, the heightened levels of insulin leads to glucose intolerance and insulin resistance, often resulting in diabetes.
The liver metabolizes fructose directly, and any excess fructose increases triglyceride levels, which are also stored in the body as fat. Glucose serves as a source of energy for the cells and we need a small supply present in our blood stream to keep cells functioning correctly. Fructose serves no other purpose in our bodies so the excess levels are essentially fatty deposits and our bodies recognize them as toxins that must be removed. The first place damaged by these toxins is the liver itself, where fructose has the same effect as alcohol.
Elevated levels of glucose and fructose both stimulate the production of advanced glycation end products (AGEs), which is the result of oxidative stress to the cells. Accelerated aging, inflammation and other diseases may result. Fructose accelerates this process at a rate seven times faster than glucose. Fructose also increases the production of uric acid, high levels of which are indicated for gout, kidney stones and hypertension.
Excess sugar and fructose in particular, feeds pathogenic bacteria in your gut, which can lead to digestive disorders and inflammation. Sustained high fructose diets can result in leptin resistance, which is a hormone that helps to regulate our metabolism and appetite. This feeds rapid weight gain. Fructose actually stimulates hunger desires in the brain, whereas glucose does not. The more fructose you eat, the more resistant you become to it and the more you want to eat.
The answer is to avoid packaged foods that are high in sugars and have refined sugar and starches as primary ingredients. In addition to high fructose corn syrup, products with names like malt syrup, corn syrup, maple syrup, honey and molasses are all likely to have high fructose levels. Keep fruit consumption under control, but there is no need to eliminate fruit entirely as fruits supply many essential vitamins, antioxidants and fiber. Use nutrient-rich vegetables as a good source of complex carbohydrates that provide our bodies with the source of glucose energy we need without spiking insulin levels. The most important thing is to recognize that too much sugar of either variety is not helpful to your diet and health.