August 31, 2015
For all of the new readers, here is a redo of the high fructose corn syrup conundrum! This article is heavier on the science. Take home points are highlighted.
We all are paying more attention to the effects of lifestyle choices on our health. The primary lifestyle choice that is hurting us is the over consumption of refined sugars.
Fructose is a natural sugar found in fruit, honey and root vegetables. Historically, we consumed fructose in these natural whole foods. Since the 1970's we have had a major rise in fructose consumption, primarily as a beverage. We are consuming it daily in juices and sweetened drinks like soda, energy drinks and sports drinks. The advent of government subsidized high fructose corn syrup (HFCS) has provided companies a very cheap source of sugar to sweeten beverages and processed foods. Cheap and sweet. Not a good combination for humans.
From the 2010 national health and nutrition examination survey, we observe data that Americans consumed around 24 grams of fructose per day in the 1970's. Now that number is in the 55 gram per day range. Adolescents take the prize at 70+ grams a day. This is equal to 17+ teaspoons(packets of sugar) a day!!!!! This is a bolus of calories, but this is not the whole story.
The story:
A major factor in the diabesity epidemic is the constant and excessive exposure to fructose, alcohol and certain protein dervided amino acids. For this article we are going to stay primarily on fructose.
How does the body see fructose?
The liver is the location for the metabolism of fructose. The majority of ingested fructose goes to the liver where it is metabolized to fat without the control of the hormone insulin. This is not good. The body likes to control the metabolic system through feedback loops that shut off when calorie/sugar/fat contents are sufficient.
Fructose directly turns on genes that increase fat deposition! Why would this be??? Let us look at gorillas. They gorge on fruit during the natural fruit season in the fall in order to produce fat for the long winter. This is sort of like a polar bear gorging on seals in the fall to survive the winter. Nature has a plan. Where does it go wrong?
Humans!
We take seasonal fruit and give access to them year round. We make juice and demand that children get juice or milk in school when water is the best choice. We make HFCS and make it cheap and accessible all year long in soda and beverages. Oops. We have just produced a mismatch of our genetically perceived environment and the true environment. We have a genetically predisposed seasonal fruit metabolism style with fructose exposure all year long.
(Science: Fructose also causes a decrease in the enzyme lipoprotein lipase, which keeps fat particles in the blood circulation. Fructose also has an effect on increasing the transcription of genes that promote glucose production in the liver and thus more glucose release. The end result is excess blood sugar, the development of insulin resistance, type II diabetes mellitus and leptin resistance.)
So, fructose used to be useful during periods of feast and famine. What used to be helpful is now dangerous with constant exposure. Nature always has a plan.
And this is not the end of the story.
Fructose also is a well-known driver of reactive oxygen species (ROS) formation. ROS are chemically reactive molecules that have an unpaired electron. Dr. Nagy has a great analogy for ROS. Imagine a single guy being invited to a couple's party. He doesn't care whom he hooks up with as long as he does.
In the cellular world the unpaired electron will attack any cell and cause stress and damage as if the single guy goes after your wife. Cells suffer DNA and protein dysfunction, which in turn causes the cell to not perform properly.
In other words, excessive fructose intake promotes the production of detrimental chemicals in the blood stream that hurt our bodies at the cellular level. This is another root cause of disease.
Now that the case for fructose has been laid out. What to do?
The first thing to do is to reduce and preferably eliminate sugar-laden beverages including juice. Get soda or sports drinks out of the house. Drink mostly water or unsweetened teas.
Second, reduce how fast the sugar is absorbed by adding fiber to your diet. The best sources of fiber are sweet potatoes, vegetables, beans and whole fruit. Adding fiber to every meal is a brilliant idea to reduce blood sugar spikes.
Third, exercise more to burn sugar so that it can't be used to make fat.
Fourth, increase the intake of bright colored vegetables and fruits, which contain natural chemicals to reduce the burden of ROS. Spices, dark chocolate, nuts and berries have very high ORAC (Antioxidant strength) scores.
Fifth, read labels and avoid foods with fructose or HFCS in them.
For further understanding, I would encourage the viewing of Dr. Lustig's webinar. http://www.sugarshockblog.com/2009/09/sugar-the-bitter-truth.html.
My take home point today: Fruit is ok, sugar drinks are not!
Dr. M