Are carbs and sugars bad news for the American diet?

October 10, 2013

I’m a nutrition consultant for various food and beverage companies, but my opinions are my own.

I have contested the view that “sugar is toxic” on more than one occasion. So of course I was interested to hear what two qualified professors of nutritional research, Joanne Slavin, PhD, RD and Mark Kern, PhD, RD, CSSD, had to say about carbohydrates and sugar at a recent event.


Why do you think carbohydrates – and sugar in particular – are receiving more attention than ever as the cause of obesity? 

Mark Kern (MK): I think many people are looking for a scapegoat for the obesity epidemic. That is compounded by poor research and inaccurate dissemination of research results by researchers, practitioners, and the media.

Joanne Slavin (JS): The search for a single cause of nutrition problems seems to be our approach. And we have spent the last almost 40 years – since the 1977 Dietary Goals – obsessing about fat. So carbohydrates, particularly sugar, are our new scapegoat. In most evidence-based reviews, sugars – total or added – are not linked to negative health outcomes. But it is easy to hate sugar so that seems to be the trend.

Some people are now saying that the Law of Thermodynamics (calories in vs calories out) is oversimplified and inaccurate. Do you agree? If so, how can health professionals best help people lose weight and maintain it?

JS: All human subjects are different. With a dietary challenge, some subjects respond more than others. So calories count for all of us, but it is not a fair system and certain people will be more prone to gain weight than others. Diets like Atkins, that are low in carbohydrate, work well for many reasons, especially when you consider the average diet is 50% carbohydrates and you cut out carbohydrates. But my opinion is that it is a better use of time to worry about calories.

Dr. Slavin, you said that the recommendation for added sugars to be 25% or less of the calories in our diet is based on the fact that if children get more than this they don’t get enough calcium. Can you explain that a little further? 

JS: There was no data available to set an upper limit for sugars according to the IOM report.  Therefore, they did some modeling and found that calcium intake was below recommended levels when added sugars comprised 25% of calories. See more here.

Dr. Kern, as you mentioned, most of the studies that show negative effects of fructose are with unrealistic amounts being consumed at one time. Why is this not more apparent to lay people who are reading the quick summaries of these studies? How can we rectify that so people understand what is actually going on in a study?

MK: I think it is a combination of inadequate information provided by the media, researchers, and practitioners. During scientific meetings I’ve seen some of the key researchers themselves ignore the fact that the amount of whatever sugar they fed or asked subjects to eat was much higher than typical levels , so much of this rests on researchers who don’t report their studies in an open way that truly educates the public.

What do you think is the number one solution to obesity?

MK: I’m a little torn between increasing physical activity and decreasing energy intake, but since studies often demonstrate that adding physical activity doesn’t reduce weight, I’m going with reducing energy intake. The trick is figuring out how to get people to do it. I think that’s where one solution might not be best for everyone and more people should consider using the services of a registered dietitian.

JS: Hard work. I don’t see us curing obesity with nutritional micromanagement. As long as we have long commutes, sedentary jobs, and don’t walk our dogs we will continue to be overweight. So best solution is the calorie one – eat better and be active.

What interesting takeaways regarding the obesity epidemic, thermodynamics, the best diet, physical activity and what it takes to achieve a healthy lifestyle!

Share Your Thoughts

Your email address will not be published. Required fields are marked *