My last blog post was about fat and its affect on the brain. I was surprised when one of my students asked a follow up question. Why do people say that HFCS is so bad for you? This meant two things. 1. Somebody actually read my blog and 2. I was going to have to write another one about nutrition. Like the Godfather, "just when I thought I was out, they pull me back in."

On this subject in particular, there is a lot of fake science out there. I would fail my ninth graders and their future first born children if they conducted some of the “MD and Ph.D." endorsed experiments I found.[i] However, I came upon two particularly interesting studies that were not in this category.

The studies were done in parallel at different places. They compared the level of obesity caused by HFCS vs sucrose when administered as part of a diet. Both studies were published at about the same time (2009-2010), compared the effects of fructose to other sugars, and were conducted by reputable scientists. Here I look at a paper written by Bocarsly (2010) in the Hoebel lab down at Princeton. You can look at the second, by Stanhope. It is in the references.

The Experiment

In the first experiment there were four groups of male rats: 1. Free access to food 2. Free access to food + HFCS 3. Free access to food, but HFCS half the day 4. Free access to food but sucrose half the day. The experiment lasted 8 weeks. Group 3 showed the greatest significant weight gain, implying that the HFCS was responsible for the additional gain in weight. There are some other really interesting trends you can see here. For example, the animals consumed a similar number of calories despite the difference in diet. Interestingly, the HFCS groups consumed more calories from food than the sucrose group. This means that calorically the HFCS group consumed less sugar than the sucrose group. There are other interesting trends, but not ones that I saw much follow up data for. (Link to data)

The second experiment went 3 times longer, 6 months. Four groups were examined 1. Free access to HFCS and food 2. 12hr access to HFCS and food. 3. 12 hour sucrose and food. 4. Free access to food. Males consuming HFCS gained more weight than those that ate only food. Much of this weight was gained in fat. The groups consuming HFCS had larger fat pads than the controls, and more of that fat was gained in the abdomen. (The sucrose group was excluded in males) Females consuming HFCS gained more weight than the other two groups, 3 and 4. I didn’t see caloric data for the second experiment. (Link to data) The female HFCS groups began weighing more than the males at 5 weeks, and the difference became significant at 25 weeks. I was a little surprised by the inclusion of females in this experiment. Because of shifting hormones, it can be difficult to attribute weight gain to the variable.

They concluded that HFCS contributed more to obesity than sucrose or food, a mix of molecules. 1 2 Fat is stored in sacs, and it is very interesting that the abdominal sac, beer gut, grew the most in the fructose fed rats. Accumulation of abdominal fat is actually worse than accumulation of other kinds of fat. Stanhope found similar evidence but he compared glucose to fructose. In this case fructose contributed more to visceral fat. From these two studies one could conclude that high fructose diets would generate a larger beer gut than diets high in other sugars. . . right? Unfortunately, it is not that simple.

Here is the problem:

As interesting as it is, you can’t draw conclusions from one study. There are many studies concerning sucrose, fructose, and obesity. Unfortunately many of these seem to refute the Stanhope and Bocarsly papers. 3 At the top of those reasons is the evidence that sugars don’t effect obesity at 25%, a direct contradiction.[ii] 3 4

BMI, the method many researchers use to study obesity, is not an adequate indicator of belly fat vs. subcutaneous fat. Basically if your BMI increases it could be a result of visceral fat, subcutaneous fat, or even just muscle. More importantly BMI provides little understanding as to the mechanism of what sugar is doing. So studies that may have provided more information about the subject don’t help to answer our particular question because the majority of the data was BMI.

Here is what I am drawing from all the evidence I looked at, again after I excluded the ones with horrible, ugly experimental designsn.

1, I did not see any epidemics that arose from diets low in sugar.

2. There is mounting evidence that sugar AT A CERTAIN LEVEL raises the level of triglycerides in the blood, increases obesity, and leads to insulin resistance. 6 7 8

3. Nobody is quite sure where that level is. 3

4. I have seen evidence for long term effects of high sugar consumption by pregnant women on their children. (Let’s be clear, this is from a single study) 9

5. Sometimes you really just want to draw false conclusions from data to make writing your blog easier, more interesting, and certainly more sensational.

Here is the discussion. In large amounts HFCS, a mixture of fructose and sucrose, might be worse for you than sucrose alone. The data does not seem to be strong enough to make a definitive statement. The following is more concrete. There is more simple sugar in commercially available foods than there should be. In a 2000 calorie diet, with 25% of calories coming from pure sugar or 500 calories, you could drink 2, 20 oz bottles of Sprite, and nothing else containing sugar.

The World Health Organization said, in 2003, that no more than 10% of your calories should be from sugar. Many others have shown the beginning of metabolic syndrome at levels around 25%. I need to cut down on sugar.

I was really hoping to dispel some myths when I started this article, but there is just too much contradictory evidence out there. I couldn’t really make definitive statements.

But here is something that I can address:

Is raw sugar better for your health than refined sugar? The brown in raw sugar is just a tinge of color from the small percentage of molasses left in the sugar. The brown does not make it healthy. There are also some minerals in raw sugar. None of that will matter if 30% of your calories are coming from sugar. There is a good chance that you will increase your fat content, increase the levels of fat in your blood, and possibly start yourself down the path to insulin resistance. The same goes for agave nectar, sugar cane, and any other source of sugar. There is no heart healthy sugar.

Some people make the argument for raw sugar claiming that it is “natural[iii]” and is therefore better for you. Opium, marijuana, crocodiles, bacon, Rush Limbaugh and the most powerful neurotoxins in the world are all natural. Eating them is not good for you. NATURAL DOES NOT MEAN HEALTHY. It can be argued that like fruit Raw sugar is natural, but unlike fruit raw sugar does not have the added benefits of fiber, which will manage the absorption of sugar, and vitamins.

Fruits have fructose in them. Does this mean that fruits are bad for you? Absolutely. If you snort them, bludgeon someone with one, or eat fruits in excess, bad things will happen. I have no doubt that excess fruit consumption will lead to increases in metabolic syndrome. More importantly, fruits come with other things, specifically fiber, which will slow the absorption of sugar in to the blood. They also contain vitamins, minerals, and other nutrients. So don’t stop eating fruits, but you can certainly eat too much fruit/sugar. Mom and Dad, what you may want to do is remove fruits from the snack bowl, and replace them with vegetables. Make fruits a regular controlled part of your meals.

In the end, and I hate to say this, more data are necessary. BMI needs to be taken with additional data including blood triglyceride levels, glucose/insulin challenges, and fat depot accumulation. If you are a researcher, get crazy, go ahead and stick that mouse in the MRI machine. Get more accurate numbers on lean mass and fat mass. If you are doing a "sac" weigh the amdominal fat pads seperately. If you are a doctor, take the time to evaluate a patient on more than just height and weight. Do some actual diagnostic work. Experiments need to be run with proper controls and designs. We just aren’t going to get a good answer until we do those things.

Thank you to Cara Solina and Kalil Cassimally.

This seemingly innocuous but oddly disturbing image is once again the work of Cara Solina, who has nothing better to do with her time and is available to create disturbing images for your blog as well. (Contact her through me)

Next time:

In light of Cory Monteith’s overdose, we will be looking at heroin, but not the fun part. Rather we will look at the creative way it destroys your peace of mind, or what George Koob calls "The Dark Side of Addiction."

End Notes