One of the best research presentations you can find on ‘the bad effects of sugar and fructose intolerance on health’ is the one by Dr. Robert H. Lustig, a professor of pediatrics and an obesity specialist at the University of California, San Francisco.
I got to learn a lot from his video presentation entitled “Bitter Truth Of Sugar.”
This video is going to take more than 90 minutes of your time to watch… but these 90 minutes will be worth more than 1000 hours you spent on other things.
Here is the video in which Dr. Lustig explains his research results on fructose:
Dr. Robert is proving some shocking truth on the ‘sugar’ that we love to savor. According to him, it is the No.1 villain responsible for major health hazards like type-2 diabetes, obesity, non-alcoholic fatty liver disease, dental caries, inflammation, hypertension, insulin resistance, leptin resistance and many more.
The fructose is full of empty calories. It is a toxic substance similar to alcohol.
Plainly speaking….daily fructose consumption is like a slow poisoning of the body.
These days some research is being conducted on the ill effects of sugar on health. Every study results are confirming most of what is said by Dr.Lustig on this matter as valid.
Let us have a detailed look into some of the major health issues that are caused by fructose.
Fatty Liver Disease (Hepatic Steatosis)
The normal glucose from normal sugar can be converted into energy by each and every cell of the body. But fructose can be broken down only in the liver.
The liver is unable to handle the excess amount of fructose and converts the excess fructose into triglyceride, a kind of fat. It also gives rise to the formation of free radicals and uric acid.[5,6,7]
The fatty liver, because of the excess triglyceride deposits, gives rise to several other diseases besides damaging the functioning of the liver.
The health and protection of the artery wall are ensured by the nitric oxide. The uric acid formed in the liver out of the fructose suppresses the production of nitric oxide. It can even cause cancer and kidney disorders.[13,14]
Because of the uric acid that reduces the production of nitric oxide, the artery walls become weaker and get infested with plaques that give rise to several cardiovascular diseases including heart attacks.[15,16]
Difference Between Fructose And Glucose
Fructose Causes Insulin Resistance
Sucrose (normally the added sugar), fructose corn syrups and fruits contain both glucose and fructose.
As we have just discussed before, glucose can be turned to energy by any cells in the body. Regular supply of sufficient glucose is important for the body to meet its energy requirements.
Only the liver can metabolize the fructose. The normal amount of fructose processed and stored by the liver in the form of glycogen in the liver and it does cause any problem.
When the body is on short of glucose supply, the body uses the glycogen to produce energy.[17,18]
With excess fructose consumption, more and more glycogen is produced than the body needs, the unused glycogen will be turned into fat deposits (triglycerides) which gradually leads to the development of non-alcoholic fatty liver disease.[19,20,21]
Non-alcoholic fatty liver and insulin resistance have a cause-effect relationship. Few of the major studies have verified ‘fatty liver’ as one of the major reasons for insulin resistance.
I am sure that you already know that insulin resistance mainly causes major diseases like Type2 diabetes, heart ailments, obesity, etc..
If we think wisely and eat wisely, many of these diseases can be controlled by reducing the intake of fructose as much as possible. Fructose is really bad for people who have already crossed their prime age, but those engaged in energetic physical activities can tolerate more fructose than others.
Fructose Gives Rise To Leptin Resistance
Leptin hormone plays a very important role in directing the brain centers to decide when to generate and suppress the appetite. This hormone gauges and maintains the energy balances in the body.[26,27]
Fat cells in the body produce the leptin hormone.
When the body has sufficient fat storage for required energy production, more leptin is released into the bloodstream indicating the brain that the body has enough energy in store.
The brain decides when the body needs to eat food depending on the signals got from the leptin levels in the blood.
Leptin hormone functions as coordinator between brain and body in maintaining the energy balance.
Obesity occurs when there is less production of leptin hormone in spite of massive fat storage, or it is released sufficiently by the fat cells, but it is not sensed by the brain.
The excess fructose consumption increases the insulin release into the bloodstream. As the insulin levels become higher than normal, it blocks the leptin signal to the brain.
According to Dr. Lustig, if the insulin levels regularly remain high in the bloodstream it will gradually lead to full grown leptin resistance. Other studies too seem to be agreeing with findings of Dr. Lustig.[28,29]
Excess intake of fructose can increase higher levels of triglycerides release into the bloodstream by the liver.
Triglycerides, a kind of fat, block the leptin hormone signals to the brain.
Dr. Lustig’s explanations on fructose effects on health have not gone well with many of the health experts as many do not fully agree with his arguments.
The functioning of the brain is so complicated; there is a need for more continuous studies and further research to establish a close relationship between leptin resistance and fructose.
If The Fructose And Added Sugar Is Bad; What About The Fruits With Fructose?
Fructose from added sugar, fructose corn syrups, beverages, and fruit juices are harmful to health as we have already seen above.
The fruits and certain vegetable also contain fructose in a substantial amount.
Are we not risking our health by eating fruits that have fructose in them?
Absolutely NOT… Fruits are safe and healthy as part of a balanced diet.
The real problem with fructose comes to effect depending on the quality and amount of fructose contained in the food we eat.
The fructose content in added sugar, fruit juices, beverages, and fructose corn syrups are very high and also in a quickly digestible form. They bring a sudden spike in large quantity fructose intake. If these foods and drinks are regularly taken, it will lead to metabolic syndrome and all deadly disease we discussed at the beginning of this article.
The fructose in full fruits is NOT harmful for many reasons.
The amount of fructose found in fruits is negligible, and the density of fructose in it is suppressed by the fiber and water present in it.
It takes much longer time for the fruits to be chewed and digested….so the fructose absorption into the blood and its transportation to the liver are minimal and slow.
The fructose in the fruit is completely not absorbable by the body as the fiber in the fruit itself will act as a block.
Most of the vegetables we eat too have a bit of fructose in them.
Glucose is the form of energy you were designed to run on. Every cell in your body, every bacterium — and in fact, every living thing on Earth — uses glucose for energy.
It is estimated that a normal diet plan with a balanced amount of fruits and vegetables will make us consume not more than 15 grams of fructose per day.
Whereas, a single bottle of soft drink (coke) with added sugar contains more than 73 grams of fructose in it.
Fruits and vegetables also contain a whole lot of vitamins, minerals, enzymes, and other nutrients which will naturally counter the negative effects of little fructose found in them.
Dr. Lustig also opines that fructose in fruits does not harm the body as only a permissible amount of fructose found in them.
There is NO reason for you to avoid fruits in fear of fructose….it will do NO harm to the health as nature has planned it already in that way.
The Bottom Line
Dr.Lustig expresses his concern and worry over the food habits of the people now in America and the world over. By and large, major portions of the daily diet of the people consist of fructose-rich foods and drinks.
This is perhaps the number one reason for the astonishing increase in obesity, diabetes, and non-alcoholic fatty liver issues more than ever now. One-third of Americans suffer from these diseases.
More and more peoples are developing insulin resistance and leptin resistance.
Dr. Lustig’s’s findings and theories are probably only the tip of the iceberg. There is a need for extensive studies to establish the undeniable links between fructose with diabetes, non-alcoholic fatty liver diseases, heart ailments, and cancer.
Dr.Lustig has succeeded in presenting the repercussions of high fructose intake as conditions that have a strong association with those diseases.
Understanding the bad effects of fructose consumption gives us enough reason to shun the habit of having sweetened soft drinks, fructose corn syrups, foods with added sugar, etc. totally.
Lustig’s talk has all the ingredients to motivate us to be cautious and on a self-imposed compulsion on having as little sugary foods as possible in our daily diet plan.