Wednesday, September 18, 2013

Is Sugar All That Bad?

Last week I asked the American Institute for Cancer Research (AICR), via a comment on their blog, if they could shed some light on the finding that when Cubans entered their Special Period in the early 1990s (a time of economic hardship after the dissolution of the Soviet Union) they lost weight and lessened their risks for diabetes and cancer via a change in lifestyle and diet, a diet that came to depend heavily on sugar and rice.
"Diet composition in Cuba also changed during the study period. By 1993, carbohydrate, fat, and protein contributed 77 percent, 13 percent, and 10 percent of total energy, respectively, whereas in 1980 their respective contributions were 65 percent, 20 percent, and 15 percent. The primary sources of energy during the crisis were sugar cane and rice."
- Impact of Energy Intake, Physical Activity, and Population-wide Weight Loss on Cardiovascular Disease and Diabetes Mortality in Cuba, 1980–2005, American Journal of Epidemiology, 2007
The AICR recommends avoiding sugar to prevent cancer. They say that sugar sweetened beverages "cause weight gain and obesity." So, why did Cubans lose weight and lower their cancer risk while eating more sugar, and more carbohydrate overall? I thought if anyone could tackle that apparent conundrum it would be a research institute willing to promote dietary intervention for cancer prevention. After all, in 1994 the AICR "provided core grant funding for The China Study, a seminal project conducted by Professor T. Colin Campbell." And Campbell has spent a good portion of his career advising the consumption of a low-fat, whole food, plant-based diet ... one that essentially eliminates animal foods, and so one that gets a good portion of its calories from carbohydrates, of which sugar is one.

I don't believe sugar intake, by itself, is the cause of weight gain and obesity. I don't believe it causes cancer or diabetes. I don't even think sugar is unhealthful. It's just a carbohydrate.

Dr. McDougall argues these points well:

The McDougall Newsletter: Sugar, Coated With Myths, 2006
The McDougall Newsletter: Sugar, 2010

It's difficult to measure the impact of a discrete nutrient, in this case sugar, when it is operating in a dynamic, intricate, and highly interdependent system - the human body. This is one reason why nutrition researchers now focus on dietary patterns in lieu of single nutrients. It could well be that within the context of a low-fat, whole food plant-based diet, sugar is benign. (Indeed, a high-fat, high-sugar dietary pattern, a "meat-and-potatoes" pattern, has been linked to increased risks for cancer and diabetes.) This is my hunch. This is what I thought AICR would say to me. Instead, they just deleted my comment. It makes me wonder what groups are funding them these days.

Dr. McDougall took up the topic of dietary patterns back in 2006 before it went mainstream:
"The main reason sugar has a bad reputation is because of the company it keeps. People living in Western societies eat loads of rich foods that make them fat and sick. Along with their high intake of meat, dairy, and refined grains, they also eat a lot of simple sugars. In this caldron of malnutrition, sugar’s exact contribution becomes indistinct. But, in most people’s minds, sugar is the villain — the scapegoat, taking focus off the animal-foods and free fats (vegetable oils), which are much more of a burden to one’s health than simple sugar is."
On a related note, I think taxes on soda and sweetened beverages are wrong. They are not being levied for health reasons. They are being levied for political reasons. If it was about health then there would be taxes on processed meats like bacon, sausage, and hot dogs, and on junk foods like chips and cakes.

Sugar And Diabetes, Part II
Sugar And Diabetes
Study: People Who Eat More Sugar Weigh Less


RB said...

The problem with sugar-phobia is that it causes people to avoid fruits. The distinction between refined sugars in soft drinks and process foods with the complex sugars in fruits gets lost in the discussion.

The sugar phobia may have started with the saturated fat phobia in the 1970s. Refined sugar (including HFCS) was substituted for fat in processed foods to make them "low fat". However these low foods had just as many or more calories as there fat counterparts. They were also designed to be over consumed. We just kept getting fatter. So sugar became the new bogeyman.

I think our real phobia should be to highly processed foods, snack foods and fast foods. Eating sugar in the form of whole fruit is a good alternative as part of a plant-based diet with perhaps a small amount of animal products.

Angela and Melinda said...

Thanks for your clear thinking on this, Bix, and for pointing out the anomalies in the argument about the evils of sugar!