Glucose vs. Fructose: Differences and Effects

Sugar is one of the most vital ingredients in your daily meals. Many people start their day with a cup of tea or coffee containing sugar and end the day with a delicious dessert, which makes sugar an integral part of your day-to-day routine. Sugar is not just an additive that adds sweetness to the dishes, it’s a complex compound that comprises several units/monomers of monosaccharides. Usually, sucrose is the prime type of sugar everyone consumes. Sugar is a natural compound found in plant tissues. Honey, fruits, and sugarcane are the prime sources of raw sugar. People consume white sugar, specifically from the sugarcane plant. Sugars can get divided into simple and complex sugars. For example, sucrose is a type of compound sugar. It is a disaccharide containing two monosaccharides, glucose, and fructose.

On entering the human body, glucose and fructose react differently. Studies indicate that these sugar units have an enormous impact on the blood glucose level and insulin. In addition, the rise in their level in the body can lead to several chronic diseases. Thus, it is vital to check your blood glucose level often, as even a single spoon of a sweet dish can negatively affect your body. 

Why is it Essential to Measure Blood Glucose Levels?

Glucose is an instant source of energy in the body. Insulin acts in coordination with glucose, and helps the glucose present in the blood to reach the organs so that the metabolism remains active. 

Diabetes is the most common disorder faced by people with either insulin resistance or reduced insulin production. But it is a misconception that blood glucose level is only related to diabetes. Several other factors can affect the blood glucose level. Several glucose-related diseases and factors fall under hyperglycemic and hypoglycemic disorders. Hyperglycemia is the increase in blood glucose levels, and hypoglycemia is the fall in the blood glucose level.

Additionally, glucose or sugar affects the (BMR) basal metabolic rate and the level of calories in your body. Therefore, excess consumption may lead to obesity. Thus, measuring blood glucose levels from time to time is important. 

The old-school method of measuring glucose is through a glucometer by pricking the index finger of your left hand to get a few drops and then placing it on the test strip. But this method requires time and will not always show an accurate reading. It is here where HealthifyPro 2.0 stands apart. HealthifyPro 2.0 grants you the power of 5. The package includes a constant glucose monitor (CGM), the help of several qualified coaches, a calorie monitor, a smart scale, and a metabolic panel that compares around 80 metabolic parameters.

The constant glucose monitor is stuck to your arm and constantly tracks your glucose levels. The personal coach assigned to you also keeps a tab on your glucose levels and provides dietary and lifestyle advice.  The smart weighing scale displays the state of your body under 12 different parameters. It syncs with your phone and records the data giving you real-time analysis. Finally, the metabolic panel provides you with an instant report of every metabolic activity in your body, including the levels of fluids. Thus, HealthifyMe Pro 2.0 is a complete package to improve your lifestyle. 

Mechanism of Glucose and Fructose Entering the Body

Hydrolysis, or the breakdown of sucrose (sugar) entering your body, results in glucose and fructose formation. The sugarcane liquid is further extracted and crystallised to form sugar, chemically known as sucrose. 

The disaccharide sucrose is composed of the monosaccharides glucose and fructose. However, even though both are monosaccharides, their metabolic pathways differ in the human body. Sucrose is a non-reducing sugar that on entering the body, splits into aldose (glucose) and ketose (fructose) sugars through the enzyme sucrase, which then enters the bloodstream. 

The HealthifyMe Note 

Fructose and glucose (monosaccharides) are both components of sucrose (disaccharide). Both enter the bloodstream during the consumption of sugar (carbohydrate). Although these belong to the same class, they differ in metabolism, absorption, and utilisation in the body. 

What is Glucose?

Glucose is a simple sugar (carbohydrate) that is the most abundant monosaccharide. It is the most crucial energy source for all living organisms. It is stored in plants as starch and in animals as glycogen. Glucose is in a free state in plants and fruits. The glycogen stored in the liver is broken down into glucose for energy through glycogenolysis. 

Around 300g of glucose is produced daily through food intake and metabolites. When you consume food, the sweet receptors on the tongue respond to glucose, and the food consumed forms a bolus. This bolus during chewing and swallowing starts breaking down through the enzyme amylase in the saliva, where glucose metabolism starts. 

The food particle gets broken down entirely in the gut, and glycogen gets stored in the liver for further use. The stored glycogen is broken down into glucose through several enzymes whenever there is a requirement for energy. The produced glucose on the other hand gets transported to the cell membrane through several transport proteins. A set of hormones constantly regulates glucose metabolism in your body. 

Factors Affecting Blood Glucose Level

The glucose level in the bloodstream can be affected even by minute stimuli in the body. It is best to note that artificial sweeteners do not affect blood glucose levels. The significant factors that can affect the above level are as follows.

Hormones that Increase the Glucose Level

• Glucagon
• Adrenaline
• Thyroxine
• Glucocorticoids

Food Intake

• Excessive food intake, especially high carbohydrates (sugars, rice), can increase the blood sugar level. 
• An inactive lifestyle, even after regular food consumption, will increase the blood sugar level.
• Dehydration may also lead to a rise in blood glucose levels.

Insulin

Not enough insulin can increase blood glucose levels as insulin resists excess glucose production.

Physical Factors

• Stress
• Injury or short-term pain
• Sunburn

Menstruation

Period cycles in women lead to the release of several hormones, increasing blood sugar levels.

Illness or Infection

Whenever a pathogen enters the body, the body undergoes several mechanisms to fight it, releasing several hormones. These hormones can increase the blood glucose level. 

What is Fructose?

Fructose is also a simple sugar that occurs naturally in plants. It is a dietary monosaccharide that gets directly absorbed into the bloodstream. Out of all the sugars, fructose is water-soluble. You can find it in trees, vines, honey, and most root vegetables. We can commercially extract fructose through sugarcane, maise, and sugar beet. 

The maximum amount of fructose is absorbed only with equal quantities of glucose. Few studies show that fructose is not fully absorbed in the small intestine. To test this, the patient needs to undergo a hydrogen breath test. Just as glucose production and supply involve the process of glycolysis and the enzyme glucokinase, fructose gets produced, absorbed, and supplied by the fructolysis and the enzyme fructokinase. Fructose may cause absorption-based disorders, such as malabsorption and fructose intolerance. 

Fructose in natural products may not pose a significant issue for your digestive system, but a high fructose concentration containing food products can be harmful to your system. For example, you can find high fructose corn syrup in food products like soda, ice cream, energy drinks, ketchup, and snack bars. Such a high intake of fructose-rich food items can affect the absorption level. Hence, fructose may remain undigested and unabsorbed. 

Difference Between Glucose and Fructose

Even though fructose and glucose are both simple sugars or monosaccharides, they differ in various characteristics. A few of them are as follows.

• Fructose does not fluctuate like glucose. The average level of fructose is 315 mg/ dl.
• Increased glucose levels immediately impact the insulin level in the body because insulin is the major glucose transporter. In contrast, fructose intake does not directly affect insulin levels, as fructose gets partially digested in the liver.
• The human body can digest and absorb glucose, which does not affect the absorption mechanism of the body. A large quantity of fructose affects the body’s absorption mechanism. 
• Glucose is the preferred energy source for the body, especially the brain and muscles, whereas fructose is not the most preferred energy source. 
• Glucose is less fat-producing as compared to fructose. 
• Glucose metabolism in the body is much slower than fructose.

Disorders of Increased or Decreased Levels of Fructose and Glucose

Fructose and glucose both entering the body benefit the body in several ways, but fructose is certainly more harmful than glucose on excessive consumption. The significant disorders that both fructose and glucose can induce are obesity and diabetes. An overview of a few of these disorders is as follows. 

Disorders Related to Fructose

Increased Level of Fructose

Fructose level increases majorly because of the consumption of packaged foods, as these foods contain high fructose levels. Natural products like fruits and honey would not increase your body’s average level of fructose. However, increased fructose levels may cause the following disorders. 

Fatty Acid Synthesis in the Liver

Fructose is released directly into the bloodstream. Hence the liver readily takes up the fructose present in the bloodstream. The function of the liver is fatty acid synthesis. If fructose consumption increases, then there is no regulatory mechanism like glucose to decrease the level. Hence, the liver takes all the fructose for fatty acid synthesis, irrespective of the quantity. This causes the fatty acids to get excessively synthesised, which harms the organ. Such a condition is called fatty liver. Fatty liver further affects insulin levels and glucose tolerance. 

Increase in Appetite

Increased fructose levels decrease the insulin and leptin levels in the body. Leptin increases appetite, causing irregular hunger pangs. You can observe it when you have increased consumption of packaged foods. Therefore, it might urge you to have more than most of these packaged foods containing fructose as the main ingredient. 

Obesity

Studies have shown that increased fructose consumption will lead to fat accumulation in several parts of the body. As mentioned earlier, fructose increases appetite and induced binge eating. This further makes it difficult to lose weight. 

Disorders Related to Glucose

Increased Levels of Glucose

The prime and well-known disorder due to increased glucose levels is diabetes and obesity.

Hyperglycemia Associated with Diabetes

Hyperglycemia is the increase in the blood sugar levels in the bloodstream (120-180 mg/ dl). It is due to low levels of insulin or insulin resistance or excess glucose consumption. It is mainly associated with diabetes, precisely type 2 diabetes, and can be genetic or because of external factors. Sudden weight gain and polycystic ovarian syndrome (PCOS) are the other factors inducing hyperglycemia. 

In people with type 1 diabetes, hyperglycemia, if detected, should be immediately treated as it may lead to an increase in the production of toxic ketone bodies in the body, which may lead to death or coma. Insulin is the only way to conquer hyperglycemia in people with type 1 diabetes, whereas for type 2 diabetes patients, oral medications are the primary treatment, followed by insulin administration. 

Symptoms of hyperglycemia-

• Dehydration
• Frequent micturition/ urination
• Headache
• Fatigue
• Skin Infections
• Weight Loss
• Vomiting
• Confusion
• Hyperventilation
• Rapid Heartbeat

You can avoid hyperglycemia by regulating the daily intake of glucose levels and maintaining an active lifestyle. 

Obesity

Sugar, or glucose, belongs to the class of carbohydrates. Carbohydrates increase body weight. Excessive carbohydrate consumption will cause obesity. Hence sugar, being a carbohydrate, if exceeding the consumption level, will cause obesity or an increase in cholesterol. 

Obesity gets directly linked to diabetes often. Once the glucose level increases through food intake, the pancreas starts insulin production in excess quantities. The insulin’s job is to transport the glucose from the bloodstream to the liver, where it will get stored for further use. However, if you’ve diabetes, insulin function gets disoriented, and the fat present all over the body, especially in the liver area, resists the entry of glucose into the liver. Thus, there is excess glucose present in the bloodstream. As a result, the pancreas produces more insulin, and eventually, the organ gets tired, leading to organ failure. 

If you lose weight during diabetes, your doctor may recommend fewer medications to get the pancreas active. Therefore diabetic patients are advised not to consume sugar: to decrease fat deposition and glucose levels in the bloodstream. 

Hypoglycemia

Hypoglycemia is usually less severe than hyperglycemia. The condition occurs when the glucose level falls below 70 mg/ dl. But it is vital to detect hypoglycemia in the early stages, as it may lead to pancreatic tumours in severe cases.

Symptoms of Hypoglycemia-

• Sweating
• Headache
• Nausea
• Fatigue
• Nightmares
• Seizures

You can immediately treat sudden hypoglycemia with a drink full of sugar. However, it is wise to treat it with medications in severe cases. It is also best to avoid alcohol and smoking as it affects glucose levels and liver function. 

The HealthifyMe Note

In contrast to fructose, which is not the body’s primary energy source, glucose is preferred by the body, particularly the brain and muscles. When ingested in moderation, the naturally occurring sugars fructose and glucose are good for your health. To maintain normal levels of glucose in the body, a continuous glucose monitor is essential. If you experience any hyperglycemic or hypoglycemia symptoms, get medical attention.

Conclusion

Fructose and glucose are naturally occurring substances beneficial for your health if consumed in moderation. However, an increase in the average sugar intake harms the body. If consumed in quantities, glucose is the primary energy source for body organs. In contrast, fructose enhances glucose metabolism and is the principal constituent of semen that provides nutrition and energy to the sperm. If fructose levels are low, it may affect the androgen and testosterone levels in males. 

Fructose does not possess much nutritional value like glucose, yet an increase in its level is harmful. Hence, it is vital to maintain normal levels through a constant glucose monitor. Consult a doctor if you are experiencing any hyperglycemic or hypoglycemic symptoms. 

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