A Bittersweet Truth: How Excessive Sugar Intake Harms Your Health

A Bittersweet Truth: How Excessive Sugar Intake Harms Your Health

Did you know that the average American consumes 17 teaspoons of added sugar per day, more than double the recommended amount? Unfortunately, indulging in sugary foods and beverages goes far beyond just satisfying our sweet tooth. The consequences of consuming too much sugar can be seriously harmful to our health. 

Excessive sugar intake contributes to a range of health issues, such as obesity, insulin resistance, heart disease and even cognitive decline. In this article, we will take a closer look at the physiological consequences of over-consuming sugar, and provide resources for maintaining a healthy, balanced diet.  

The Physiological Consequences of Excessive Sugar Intake  

Obesity and Diabetes 

Excessive sugar intake is one of the primary causes of obesity and diabetes, conditions which are deeply intertwined.  

When we eat sugary foods, our bodies produce insulin to process the sugar in our bloodstream. Over time, high levels of insulin can lead to insulin resistance, which makes it difficult for our cells to absorb glucose from the blood. When it’s unable to be shuttled out of the bloodstream, sugar causes damage to the body’s tissues. This process is at the root of many common manifestations of diabetes, such as diabetic neuropathy, retinopathy, and nephropathy. 

Independent of its effects on insulin, sugary foods and beverages are often high-calorie and low-fiber, and thus are easy to overconsume, leading to weight gain and obesity.  

Accelerated Skin Aging  

Sugar also damages the skin through the formation of advanced glycation end products (AGEs). AGEs are a group of molecules that form when sugar reacts with amino acids and proteins in our body. They accumulate in our skin as we age, making it less elastic and more prone to wrinkles. 

This process, called glycation, causes the collagen and elastin fibers in our skin to become stiff and brittle, which in turn causes the skin to lose its youthful appearance. This is one of the reasons why individuals who consume high amounts of sugar may experience premature aging of the skin.  

AGEs can also accumulate in other tissues of the body, such as the kidneys and blood vessels, contributing to other age-related diseases. 

Low Energy 

Most of us intuitively understand how sugar robs us of our energy. While it may give us a quick burst of energy, the ensuing crash can leave us feeling even more fatigued than before. The ups and downs of insulin spikes triggered by sugar intake are one reason why many nutrition experts advocate that when sugar is consumed, it should be accompanied by fiber.  

In that context, insulin release is slower, and energy can be sustained over a longer duration. This is a major difference between how nature intended us to consume sugar (via fruits and vegetables which have lots of fiber), and how humans have only recently begun to consume it (via high-fructose corn syrup, for example, which has no fiber to slow down insulin release). 

Arterial Damage 

The insulin resistance which excessive sugar intake can trigger is also a risk factor for the onset of a pernicious disease called atherosclerosis, which refers to the buildup of plaques in the artery walls.  

Over time, these plaques can grow and narrow the arteries, reducing blood flow and increasing the risk of heart disease, heart attack, and stroke. Atherosclerosis is a major cause of mortality and morbidity among diabetics. 

Neurological Dysfunction 

Finally, diets high in sugar are associated with an increased risk of dementia, Alzheimer's disease, and strokes. Research shows that in addition to vascular mechanisms, proliferation of neuroinflammation and disruption of the gut microbiome may be mechanistic candidates for how sugar causes this cognitive decline.  

Bottom Line 

Consuming too much sugar can have a host of adverse health effects that tilt us away from wellness and towards diseases. To keep our mind and body functioning at their best, it's important to be mindful of how much sugar we consume and to strive for a balanced, nutrient-rich diet of mostly whole foods. Below are a host of resources from the experts at TWC to guide you in improving your nutrition. 

Recommended Reading from TWC’s Experts on Nutrition: 


No content in this article should be used as a substitute for direct medical advice from your personal doctor or other qualified healthcare provider.  


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About our editorial team

The TWC Editorial team is comprised of various wellness practitioners from physiotherapists, acupuncturists, fitness instructors, herbalists, and MDs.

This article does not constitute medical advice. Please consult a healthcare provider for proper diagnosis and treatment.
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