the truth about the health effects of fructose

Jill Bridges, SATI STAFF

Staying ahead of the latest health trends can be extremely difficult. It seems like every single year food researchers find more information about which foods are healthy and which are not, meaning people have to keep track of this new information to make sure they are eating as healthily as possible. However, there is one food related issue that doesn’t change: people consume too much sugar in their daily diet.

If you’ve ever taken a look at the nutrition label on the back of your food packages, you’ve probably noticed that nearly every common foodstuff is filled with sugar. Even the fruit that you eat everyday contains a type of sugar called fructose that can be problematic for your health if consumed in excess amounts. Many people, however, aren’t familiar with fructose or how it affects your body, meaning they’re unaware of some of the risks of this common substance.

Here are a few facts to help you better understand the truth about fructose, and information about how too much fructose may harm your body.

A few facts about fructose

In the Western world, a tremendous amount of sugar is consumed every year. The United States Department of Agriculture estimates that the average person ingests between 150 and 170 pounds of sugar a year, most of which comes in the form of refined sugar and high fructose corn syrup. Both of these items are made using two simple sugars, glucose and fructose.

A common misconception is that all sugars are bad. Although you should make sure to never eat anything in excess, glucose isn’t inherently unhealthy. In fact, every cell in the world, including those in your body, contain glucose, and it is a molecule that is essential to all life.

Fructose, on the other hand, is a troublesome type of sugar. The main reason for this is that the human body isn’t equipped to process large amounts of fructose [1,8,9]. In evolutionary past, the only source of fructose for humans was fresh fruit. However, in modern times, fructose is in almost every food item thanks to the proliferation of high fructose corn syrup. Consuming these massive amounts of high fructose corn syrup on a daily basis has led to many health problems that you need to know more about.

Problems with your liver

The liver is one of the most important organs in your body, responsible for a large portion of energy creation and removing toxins from your system. Maintaining your liver functionality is one of the most important things that you can do if you want to live a long and healthy life. Unfortunately, excess consumption of fructose runs contrary to this goal, and can even cause serious damage to your liver over time.

Unlike other food substances, your liver is the only organ that is capable of metabolizing fructose. When your liver processes fructose, it is converted into fat, which is often deposited in your liver as well as other areas of your body. Over time, these fatty deposits can accumulate on your liver to the point that they cause non-alcoholic liver disease. If your liver suffers enough damage, it’s possible that you will need a liver transplant.

In addition to non-alcoholic liver disease, too much fat deposited in your liver can lead to a condition known as insulin resistance [3]. With this ailment, your liver will not recognize the insulin in your blood and will continue producing this substance, leading to extremely serious health consequences like type 2 diabetes [10,11]. Protecting your liver is a matter of limiting your intake of fructose.

Weight gain

Nearly everyone has had that feeling that they’ve eaten too much food in a single seating, leading to a stomach that is overstuffed. Mostly, this is because we’ve ignored the signal sent from our body to our brain to tell us that we’ve had enough to eat [12,13]. Although you may not realize it, there is a hormone in your body known as leptin that is responsible for signaling to your body that it has enough energy.

Leptin is produced in the fat cells of your body, and the bigger these fat cells, the more leptin will be produced and placed into your bloodstream. As we saw in the previous section, one of the dangers of fructose is that it is converted to fat cells which are then stored throughout your body [4]. By consuming fructose, you’re adding fat to your body, which leads to an increased production of leptin.

Eventually, your body will produce so much leptin that it will result in a condition called leptin resistance. With leptin resistance, elevated insulin levels block your body’s ability to recognize leptin, meaning it won’t be able to receive the signal that your stomach is full. This leads many people to eat more food than they normally would, and will eventually cause tremendous weight gain and potentially obesity.

Potential for addiction

Almost everyone has been touched by addiction in some way or another. However, while many of us assume that addiction can only be triggered by substances like hard drugs or alcohol, it’s actually extremely easy to be become addicted to almost any substance, and this includes sugars. Developing research suggests that continued consumption of sugar may cause sugar addiction, which may explain why it’s so hard to cut back on our sweet snacks.

The human tongue has two sweet receptors. However, because these receptors are not designed to handle excessive sweetness, eating a sugar-filled food causes your brain to trigger opioid production [2], which is a reward signal that can also relieve pain. When sugar continually triggers opioid production, it can lead to uncontrollable cravings, the exact same mechanism that results in addiction to drugs and alcohol [14,15].

When you consume large amounts of sugar on daily basis, it’s possible you will become addicted to the sugar. This will make it nearly impossible to exhibit self-control and reduce your intake of this harmful substance. Limiting your fructose intake is a good idea if you don’t want to deal with a potentially dangerous sugar addiction.

Development of cancer

Receiving a cancer diagnosis is one of the most devastating situations that a person can face. No matter the type of cancer that is found, people with a cancer diagnosis will often have to undergo physically draining treatments, such as chemotherapy, radiation, and surgery. If you have a family history of cancer, or are simply worried about suffering from this ailment, you may be interested in preventing this disease in whatever way possible, and that includes limiting fructose intake.

One of the biggest risks of eating too much fructose is the possibility of developing insulin resistance. In addition to leading to issues like obesity and type 2 diabetes, the increased insulin levels in your body and the resulting IGF-1 growth factor may eventually lead to the development of cancer [5].

There has been some solid research to show that consuming fructose, particularly artificial fructose, can trigger tumor growth within the body [16]. In addition, once cancer is present, tumors can thrive on the presence of sugar. Sugars like fructose are processed by cancer at a much quicker rate than regular cells, causing them to grow and making it difficult to treat your cancer [17].

If you want to reduce your risk of a cancer diagnosis, consider cutting back on how much fructose you consume daily.

Fructose can make you sick

Your body’s immune system is responsible for promoting healing and fighting infection. With a weakened immune system, it’s common to suffer from more frequent illness and be less resistant to bacteria. To the surprise of many people, eating too much sugar may actually result in a suppressed immune system, meaning that the sugar you eat everyday might be making you sick.

Phagocytosis is one of the most important responses of your body’s immune system. Without this key immune response, your body won’t be able to effectively fight bacteria and may be more susceptible to infection. Unfortunately, there has been a proven link between the consumption of fructose and the phagocytosis response.

If you consume ten teaspoons of sugar a day, which is well within range for the average American, it can lead to as much as a 50% reduction in the phagocytosis response [18,19]. The more sugar that you eat on a regular basis, the less equipped your body will be to fight illness. Anyone that wants to feel their best and ensure their body is capable of resisting disease should strongly consider a reduction in the amount of sugar they consume.

Uric acid production

One of the most important parts of maintaining your long-term health is making sure the chemical levels in your body are as balanced as possible. When these levels become unbalanced, it can result in negative impacts to your health, which is the primary reasons it’s crucial to eat a balanced diet. Substances like fructose can throw off your body’s delicate chemical balance, particularly in regards to the production of uric acid [20].

When fructose is processed within in your body, it results in several different by-products. One of these by-products is a chemical compound called purine. When purine is introduced into your system, it creates a substance known as uric acid. If you’re familiar with uric acid, then you probably know that it is responsible for forming crystals in your joints that cause the condition known as gout. Just moments after ingesting fructose, uric acid is produced [6].

While gout is the largest risk from increased uric acid production, it is also possible to suffer other serious conditions like kidney stones and hypertension, the latter of which may result in stroke or heart attack. If you’ve experienced any of these issues in the past, or are at risk for a future occurrence, you should lessen the amount of fructose in your diet.

Digestion troubles

When you eat food, your body transforms it into energy. Certain foods, like complex carbohydrates and proteins, are ideal for energy production. Other foods can only be used for a limited amount of energy. Fructose is one of the few substances that your body is unable to use as a source of energy, meaning it is entirely wasted calories and may lead you to feeling more tired as your body is not getting the fuel that it needs to function.

However, while your body cannot use fructose as a source of energy, it is the perfect fuel for the bacteria that is located in your stomach. For your stomach to function properly, there must be a balance of flora. When you consume too much fructose, certain bacteria will thrive in your gut, leading to a flora imbalance [21, 22]. Too much bacteria growth in your stomach, especially pathogenic bacteria growth, may result in serious digestion issues.

If you find that your stomach is constantly upset and that you aren’t digesting food as effectively as in the past, the likely culprit is a flora imbalance caused by fructose intake. Cut back on the amount of fructose you consume each day, and you should find relief from your digestion issues.

Heart disease

Out of all the conditions that can lead to a shortened life, the most common is heart disease. In fact, heart disease is the number one killer of men and women each year as estimated by the American Heart Association. Whether your family has a history of heart disease or not, maintaining your heart health is one of the most important things that you can do to increase your lifespan.

There are a variety of substances that can negatively impact your heart health, but one of the most serious is fructose. Consumption of fructose causes your liver to synthesize fats, which are then transported into your body in the form of VLDL cholesterol. At a certain point, this cholesterol will result in dyslipidemia, which is excessive levels of triglycerides in your bloodstream [23, 24].

If left unchecked, this increased level of cholesterol and triglycerides can result in heart diseases and, potentially, death. Increased consumption of fructose is dangerous for all of your organs, but is particularly threatening to your heart. Lower your consumption of fructose and increase your heart health.

Lowered memory

Memory is one of your most important tools in living a successful life. This is particularly true if you are a student trying to make their way through school. When you have an important work assignment or test to study for, it’s common to chug sugary drinks in an effort to get a quick energy boost. However, research shows that this may be doing more harm than good, as fructose may have a direct impact on your memory.

A study performed at UCLA measured the effect of high fructose diet on the brain functioning of rats [7, 25, 26]. The results of their study were extremely compelling, showing that there was a direct correlation between fructose and brain functioning. Rats in the study who consumed a large amount of fructose had much lower brain functioning and a decreased memory. This means fructose has a direct effect on your ability to learn and recall information.

Fortunately, the study also showed that consumption of omega-3 fatty acids, commonly found in fish oil, worked to reduce the impacts of fructose consumption. Make sure that your brain is always functioning at its highest level by controlling your intake of fructose.

Choose fruit

After learning about the negative impacts of fructose consumption, it’s common for many people to eliminate this substance from their diet completely. While this is understandable, it also means you would be eliminating a primary source of vitamins and nutrients: fruit.

You only need to worry about the harmful effect of fructose if you are consuming added sugars. For example, add sugars include the fructose that you would find in sodas and candy. On the other hand, the fructose that is found in fruit should not harm your body [27, 28, 29, 30]. The main reason for this is that fruit contains both a large amount of water and fiber, making you feel full before you’ve consumed dangerous amounts of fructose.

Although you should absolutely limit the amount of fructose you consume in the form of added sugars, you can eat fruit worry free. However, make sure you’re actually eating fruit, as fruit juices contain the same harmful fructose that you would find in other sugary drinks. Choose fruits instead of artificial fructose to avoid the negative consequences associated with this substance.

The sati line

Fructose is one of the most common sugars you could consume. While it is found in fruit, fructose is also an ingredient in almost every modern food item. Small amounts of fructose are generally benign, but as we have seen, ingesting large quantities of fructose can have several, negative impacts on your health. This should be a large concern of anyone in the United States, where fructose is consumed in alarming amounts.

The biggest risk of excess fructose consumption is increased insulin levels in your body, which can result in such consequences as rapid weight gain and type 2 diabetes. Additionally, fructose has been linked to such other serious illnesses as heart disease, liver disease, reduced brain functioning, and even cancer. Clearly, removing as much fructose as possible from your diet is an important part of improving your long-term health.

If you’re the type of person who’s interested in being as healthy as possible, your best bet is to restrict the amount of fructose that you consume on a regular basis. By reducing your fructose intake, you’ll feel better, be more energetic, and will be preserving your health.

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