I’m not a medical doctor or nutritionist, but I do follow research on nutrition and its affects on mental health and brain functioning. A recent study using rats, found that a diet high in high fructose corn syrup (the stuff used to sweeten just about everything these days), caused declines in memory and learning. Now admittedly, this study was done with rats and not people, but I can tell you that in my experience as a psychologist that people feel much better emotionally and physically when they limit their intake of sugar and sugar substitutes.
In the long run, you will save yourself from serious stress down the road from the health problems that can come from a high sugar diet. There’s a simple formula to consider here: the better you feel physically, the better you’ll feel emotionally. I don’t recommend making a dietary change because you feel like you “should,” because that often doesn’t work. If you make a change in your diet, do so because you want to feel better. Consider it an investment in the future for reducing stress.
Certainly, if these effects hold true for humans, having trouble learning and remembering things would be a source of stress. But even if it doesn’t hold true for humans, you’ll do well to avoid the high fructose corn syrup and excessive sugar. The most immediate change many people can make in this area is staying away from soft drinks.
Reference:
This Is Your Brain On Sugar: Study in Rats Shows High-Fructose Diet Sabotages Learning, Memory, Science Daily, 5/15/12.