Fructose in obesity and cognitive decline: is it the fructose or the excess energy?

We read with interest the review by Lakhan and Kirchgessner, proposing that high fructose intake promotes obesity, metabolic syndrome, diabetes, and cognitive decline. Their focus on the role of fructose seems premature due to confounding from energy and the heavy reliance on low quality evidence from animal models. There is a lack of high quality evidence directly assessing the role of fructose in cognitive decline. Although one cannot exclude the possibility of a link, it remains an unconfirmed hypothesis.