Houston, we’ve got a problem — sugar.

The average American consumes about 170 pounds of it, much of which comes in the form of high fructose corn syrup (HFCS) in pop.

What’s wrong with that?

Plenty, just ask Robert Lustig, M.D. from University of California, San Francisco. He appears in a widely acclaimed YouTube video called “Sugar: The Bitter Truth,” in which he shows, in great detail, how fructose causes obesity, Type 2 diabetes, high cholesterol and triglycerides, and high blood pressure.

Lustig refers to fructose as a “toxin” and “alcohol without the buzz” because its effects on the liver are like those of alcohol. Fructose causes fatty liver and cirrhosis just like alcohol does. We should avoid fructose in any food other than fruit.

We also get sugar when we eat foods with a high glycemic index, such as white flour, white potatoes and white rice. These foods cause a rapid rise in our blood sugar which makes our body make more insulin. When this happens, we also increase our body’s production of cholesterol, increase the amount of fat cells we store, increase our appetite and damage the cells lining our blood vessels (endothelium). All of these things lead to obesity, Type 2 diabetes and heart disease. Read “Ending the Food Fight,” by David Ludwig, M.D., Ph.D., or Google “glycemic index” for more information about this.

There is also emerging data linking sugar to rheumatoid arthritis (RA). Gerald Weissmann of New York University, one of the world’s experts on RA, has done much of the research uncovering this association. RA is a disease that was first identified in the late 1700s, when refined sugar first became widely available in Great Britain and France.

We all know that sugar causes cavities, but it also causes gum disease and increases the number of certain types of mouth germs that alter the immune system and trigger joint swelling. This mirrors what we have seen in our RA patients: the worse the teeth, the worse the arthritis. There is also a link between gum disease and heart disease.

Where can we find all of this fructose and refined sugar? Literally everywhere. Vending machines with pop, sweets and juice are in every nook and cranny of our society. They are found in schools, hospitals, medical clinics and businesses of all sorts. In the grocery store, pop takes up an entire aisle. Many processed foods have HFCS, including ketchup, applesauce and yogurt. Read labels when you shop and you will be shocked by how many products it is in.

Why do we seem to consume so much sugar? Well, it seems that it is a brain thing. Our brains crave sugar, salt and fat, and as we evolved this helped us identify edible foods. However, we now have supercharged sugary foods that stimulate the same reward pathways in our brains as cocaine does. This is well described in “The End of Overeating” by David Kessler, M.D. No wonder folks seem to be sipping pop all day long.

In our processed food culture, how can a person achieve health? Well, it was simply put by Michael Pollan — “Eat food, mostly plants, not too much.” Avoid refined sugar, especially fructose, unless you want bad teeth, obesity, diabetes, heart disease, arthritis and cancer.

And that is the “Bitter Truth.”