When sugar cravings set in, the last thing we might think of is our long-term mental health. However, there is plenty of evidence to suggest that we should.
We've all been there. After a stressful day, when our mood is low, it is easy to reach for a tub of ice cream or similar sugary treat. But evidence of the link between sugar and mental health is mounting - and it's not just sweets that rack up our daily sugar intake.
It was reported recently on a study published in the journal Scientific Reports that identified a greater risk of depression among men who consumed significant amounts of sugar in their diet.
One might argue that feeling depressed may lead to increased sugar consumption, rather than the other way around. However, what was really interesting about this study was that the researchers, from University College London Institute of Epidemiology and Public Health in the United Kingdom, used a mathematical model to exclude exactly that: a phenomenon they called reverse causation.
Using data from the Whitehall II study - a large group of civil servants in the U.K. - they showed that sugar consumption came before depression, rather than being a consequence of it, medicalnewstoday reports.
So while there are an increasing number of studies looking at the implications of diet on mental health, it is difficult to study the exact causes and mechanisms that link the two.
What is the evidence? And how can sugar, such a simple molecule, wreak such havoc in our brains?
Diet and mental health are linked
In 2002, a study of overall sugar consumption per person in six different countries (Canada, France, Germany, Korea, New Zealand, and the United States) - published by Dr. Arthur Westover, from the University of Texas Southwestern Medical Center in Dallas - implicated sugar as a factor in higher rates of major depression.
Since then, several other research teams have investigated the effect of diet on mental health. For example, consumption of processed and fast food - including hamburgers, pizza, and fried foods - was found to be higher in both youngsters and adults with increased rates of depression.
Likewise, female U.S. seniors with high levels of sugar in their diet had greater rates of depression than those who consumed less sugar.
Sugar-sweetened beverages, especially soft drinks, have increased in popularity and are now consumed around the world. But a study of Chinese adults - who traditionally drink unsweetened tea - showed that those who drank soft drinks had higher rates of depression.
While these studies did not set out to find the biological mechanism by which sugar affects mental health, they add to the body of evidence reporting on the link between the two.
The science of sugar
Sugars are simple carbohydrate molecules. While being essential for cell and organ functioning, our bodies have sophisticated machinery to break complex carbohydrate molecules into simple sugars.
It therefore does not need to be added to the diet, and the American Heart Association (AHA) state that "our bodies don't need sugar to function properly."topics from