Starling Fitness: Daily writings on Fitness, Diet, and Health

In the ongoing effort to stop my bingeing, I have taken the vow of “Nothing Sweet.” No sugar, no aspartame, no Splenda, no saccharin, NOTHING that tastes sweet. It has helped a little bit, keeping me from obsessing over food, but I have absolutely NO science to back it up.

Sure, every once and a while, the media trots out the studies that have shown that eating artificially sweetened foods actually made rats GAIN weight, but they never provide links to the actual studies.

Yesterday, I found them:

Behavioral Neuroscience, Vol 122(1), Feb 2008: A role for sweet taste: Calorie predictive relations in energy regulation by rats.

Animals may use sweet taste to predict the caloric contents of food. Eating sweet noncaloric substances may degrade this predictive relationship, leading to positive energy balance through increased food intake and/or diminished energy expenditure.

These experiments were designed to test the hypothesis that experiences that reduce the validity of sweet taste as a predictor of the caloric or nutritive consequences of eating may contribute to deficits in the regulation of energy by reducing the ability of sweet-tasting foods that contain calories to evoke physiological responses that underlie tight regulation.

Adult male Sprague-Dawley rats were given differential experience with a sweet taste that either predicted increased caloric content (glucose) or did not predict increased calories (saccharin).

We found that reducing the correlation between sweet taste and the caloric content of foods using artificial sweeteners in rats resulted in increased caloric intake, increased body weight, and increased adiposity, as well as diminished caloric compensation and blunted thermic responses to sweet-tasting diets. These results suggest that consumption of products containing artificial sweeteners may lead to increased body weight and obesity by interfering with fundamental homeostatic, physiological processes.

Behavioral Neuroscience, Vol 123(4), Aug 2009: General and persistent effects of high-intensity sweeteners on body weight gain and caloric compensation in rats.

In an earlier work (S. E. Swithers & T. L. Davidson, 2008), rats provided with a fixed amount of a yogurt diet mixed with saccharin gained more weight and showed impaired caloric compensation relative to rats given the same amount of yogurt mixed with glucose.

The present 4 experiments examined the generality of these findings and demonstrated that increased body weight gain was also demonstrated when animals consumed a yogurt diet sweetened with an alternative high-intensity sweetener (acesulfame potassium; AceK) as well as in animals given a saccharin-sweetened base diet (refried beans) that was calorically similar but nutritionally distinct from low-fat yogurt.

These studies also extended earlier findings by showing that body weight differences persist after saccharin-sweetened diets are discontinued and following a shift to a diet sweetened with glucose. In addition, rats first exposed to a diet sweetened with glucose still gain additional weight when subsequently exposed to a saccharin-sweetened diet.

The results of these experiments add support to the hypothesis that exposure to weak or nonpredictive relationships between sweet tastes and caloric consequences may lead to positive energy balance.

Nothing Sweet

These two studies show that artificial sweeteners cause weight gain in rats compared to those eating glucose, but what if I eat NOTHING SWEET? There is no science saying that this will help me lose weight, only that I should avoid artificial sweeteners.

All I know is that my constant obsession with food is abated when I avoid eating anything with a sweet taste. The science of weight loss is so infantile right now that we have no idea what works on a long term basis. It makes me feel quite hopeless.