Sugary diet impairs memory

Rats in a maze study performed worse when their diet was supplemented with fructose water, researchers at the University of California Los Angeles found. The team trained 24 rats to run a maze over 5 days, and then randomized them to a diet enriched with or without docosahexaenoic acid (DHA) and with or without a fructose solution. After 6 weeks on one of four diets, the rats ran the maze again from memory, the researchers reported in The Journal of Physiology. Cole Petrochko writes, Rats with a DHA-enriched diet that were not given fructose water had significantly better times on the maze than did rats given sugar, whether or not their diet was enriched with the omega-3 fatty acid. However, rats given sugar water and the fatty acid managed to perform better than ones without DHA. Rats given neither fructose nor fatty acids performed better than either fructose group, but not as well as rats with the DHA enriched-only diet. The research team noted that "the lack of [omega-3] fatty acids in the diet elevated parameters of peripheral insulin resistance, and resulted in disrupted insulin signalling in brain, and these effects were aggravated by fructose treatment" and that "dysfunctional insulin receptor signalling was associated with lowered learning performance" in the maze. In short, the omega-3 deficiency led to memory deficiency, which was amplified further by drinking sugar water. from medpagetoday