For one, past studies that looked at harmful effects of sugar on rodents provided doses of sugar much higher than the amount normally consumed by humans. The argument against these studies was that no one really consumed sugar at these toxic doses and that sugar was likely harmless when consumed in doses more consistent with normal intake. In the current study, however, Ruff and colleagues fed mice a mixture of fructose and glucose (the most common forms of sugar consumed by humans) in “moderate doses”, defined as 25% of the total calories consumed, a level that mimics the diet of an estimated 13-25% of Americans.
The other big difference between Ruff’s study and past sugar studies are the outcomes measured. Past studies most often examined blood tests or physiological “markers”, such as glucose clearance (ability of the body to process glucose or “clear it” from the blood stream), cholesterol levels and percent body fat, as the main outcomes. The current study took a unique approach, using something called Organismal Performance Assays or OPA’s. I’m not going to pretend to be the world’s expert on these, but briefly these are objective ways of examining how these animals manage behaviorally in a “real world” environment where they are placed in competition with each other for resources, such as food and mates. In other words, OPA’s scientifically measure outcomes that we really care about, like survival and reproduction-sort of like a closely monitored, scientific, reality show for mice.
The results of this study are truly fascinating. When compared to mice fed a normal rodent diet, the mice fed a diet considered normal by nearly 1 in 4 Americans fared much worse on several vital real world outcomes. Interestingly (but, I suppose, not surprisingly), the adverse effects on the sugar-fed mice differed between the males and females. Female mice fed the sugared, “American” diet were twice as likely to die (doubled mortality rate) as compared to non-sugar fed females. While male mice fed the sugar diet did not show any difference in mortality rate, they did have significantly lower competitive ability and reproductive success than their regular-diet-consuming counterparts. Of course, these are just mice. Can these dramatic effects of sugar on important health measures, such as mortality and reproductive capacity, really be applied to humans?
According to some experts in the field, they most certainly can. In fact, the health effects of sugar on humans are so dramatic that it was featured on this month’s cover of National Geographic (2). In the article, Dr. Richard Johnson, a kidney specialist at the University of Colorado Denver explains how sugar addiction is fueling the current obesity epidemic. “Americans eat too much and exercise too little because they’re addicted to sugar, which not only makes them fatter but, after the initial sugar rush, also saps their energy, beaching them on the couch”.
According to Dr. Robert Lustig, a pediatric endocrinologist at the University of California San Francisco, also quoted in the article, the toxic effects of sugar have “nothing to do with calories. Sugar is a poison by itself when consumed at high doses.” Lustig, a leading expert on childhood obesity has been lecturing about the evils of sugar for years, long before this month’s compelling study was published. Lustig’s stance has caused much controversy, with political outcries on the part of the sugar industry reminiscent of the early wars waged by tobacco companies when it was first suggested that smoking might be hazardous to one’s health. Remember how there were cigarette commercials featuring doctors smoking? Seems crazy to us now, but what about a doctor eating a doughnut? Will research evolve to make this seem similarly out of place? Perhaps, it just has.
For a great overview on Lustig’s campaign against sugar, check out Gary Taube’s article (3) on NY Times.com:
In the meantime, what can we do to protect ourselves from sugar’s dangers? There’s really only one solution. We’ve got to stop eating so much of it. Easier said than done, of course. Sugar is all around us, even for those of us who are trying to eat right. In fact, many foods that are touted as “healthy” are loaded with it, especially those labeled as “low fat”, since sugar is usually added to make these items taste better. Other “hidden” sources of sugar include breakfast cereals, granola and energy bars, and fruit juice. In other words, you don’t need to be eating candy every day to consume a lot of this stuff. The key? Read labels on packaged foods or, better yet, avoid them altogether.
When making these changes to your diet, expect to feel it. Giving up sugar, even if the amount you’re eating now is low to moderate, causes withdrawal symptoms. Believe me. I’ve been through it. To ease the pain, follow these tips:
- Drink plenty of water.
- Get enough rest.
- Spend some time outdoors, communing with nature.
- Surround yourself with supportive people (this isn’t the time to confront the neighbor who annoys you or the boss who can be difficult to deal with)
- Consider other detox strategies, such as acupuncture, massage, saunas, or hot yoga.
The good news is that once sugar is out of your system other foods start tasting better and better. And, you’re body will start feeling better and better. I know I haven’t talked a lot about sugar and pain in this article. There aren’t, honestly, many studies that have looked for a connection between them. But, there is indirect evidence that they may be linked. We know that in toxic amounts, sugar is poison to our nerves, and can lead to the painful neuropathy often seen in diabetics. We also know that diabetes is an independent risk factor for the development of painful arthritis. In Chinese medicine, sugar is believed to lead to excessive muscle spasm, and I have certainly seen evidence of this in my own practice of acupuncture. Giving up, or cutting back on, sugar often leads to less muscle spasm and nerve pain, as well as clearer skin, more restful sleep, improved digestion, higher energy levels, more stable moods, and, yes, even weight loss. Sound too good to be true? The only way to find out is to try it!
1. Ruff, J. S. et al. Human-relevant Levels of Added Sugar Consumption Increase Female Mortality and Lower Male Fitness in Mice. Nat. Commun. 4:2245 doi: 10.1038/ncomms3245 (2013).
2. Cohen R. (2013, August). Sugar Love: a not so sweet story. National Geographic, 78-97.
3. Taubes G. (2011, April). Is Sugar Toxic? New York Times Sunday Magazine, MM47.