The matter of relativity and relevance

You could hear Dr Lustig saying at 1:03:46 minute of the video that there are more non-obese people who are sick. This was in relation to the diagram he presented earlier: 

Taking that there are still more non-obese people in the U.S. than obese, it truly appears that more of the non-obese suffer metabolic diseases (0.4 x 70 vs. 0.8 x 30). 

Where are the overweight? 

We now know that of people older than 20 years in the U.S., 69% was NOT of a healthy weight, i.e up to the BMI 25, in 2011-2012. That meant that 31% of the U.S. population had the BMI up to 25. That includes underweight, which are also at health risk. But I accept that overweight has become a NORM in the U.S., so maybe that was one of the reasons why these were included in 'normal weight' blue diagram on the right. Nonetheless, Dr Lustig called this broad group comprising 70% of this non-obese U.S. population as THIN people, check the video at 58:27 minute. I was overweight with BMI 27 at my heaviest and I was far from being thin, I can tell you.

Let's continue: over a third (35.1%) of these adults from the 2011-2012 survey were obese (higher than 30% of the older data displayed on the diagram), leaving the 'only' overweight group at 33.9% of the adult population. The true healthy body weight was found only among 31% of the adult population. Quite a difference from those 70%, is it not? Now we suddenly have an opposite picture in mind: Healthy weight 31% and overweight+obese 69% of the population. I would be curious to find out the position of the oval referring to the prevalence of metabolic diseases... This data was not presented.

My question is: Do people start suffering metabolic issues only when they cross the magic BMI 30 point? I doubt so.

While we might have become accustomed to see overweight people as a norm, metabolically it is not healthy and for many being overweight is only a transition state to the obesity, while the obese tend to die prematurely, so the trend maintains itself. 

Put it together in your head and see what is happening. 

Adding up to this article I would like to bring to your attention more information why a positive energy balance, which leads to obesity, may be behind the insulin resistance more than the fructose consumption. This basically reflects the fact that the extra body weight has a negative impact on our metabolism, at least regarding the insulin resistance and hyperinsulinemia, with a possible causal link to the NAFLD (non-alcoholic fatty liver disease).

And after watching another video of Dr Lustig, you could hear him saying at 5:33 minute:

"Obesity is certainly associated with those diseases  but it is not the cause of those diseases (dementia, cancer, dyslipidemia, type 2 diabetes...). And when you do the math... obese or not, it is more than half of the U.S. population." 

I have trimmed the quotation - he basically said that it does not matter whether you are obese or of a normal weight, over a half of the U.S. population is metabolically sick.

Well, the same applies to the U.S. population in terms of being overweight and obese. Those 69% are also over a half of the U.S. population that is NOT of a healthy weight. 

To me it appears, that Dr Lustig has suddenly realized that fructose is not a leading factor in the development of human obesity as he used to say back in 2009 (it is glucose, what a secret), so now he left the obesity out and focuses on the link between the fructose and the metabolic diseases instead.

Update 9/12/2014: When reading an older work of Dr Lustig, which he published together with E. Isganaitis in 2005, I have found this:

This only confirms my point that splitting the population to obese with BMI > 30 and the remaining population, when discussing metabolic issues that are closely linked with excess body fat, calling the non-obese population of 'normal' weight and pronouncing that obesity is NOT a problem, is wrong.