This new study, published in Scientific Reports, concludes that mental illness -- particularly mood disorders -- could be directly caused by diet. Surprisingly, only men were noted to show this relationship. Women, the researchers observed, did not display any connection between mental health and high-sugar intake.
The health risks involved in a high-sugar diet have already been extensively studied. Excessive sugar consumption is linked to a variety of health conditions such as diabetes, dementia, and obesity. Nevertheless, the researchers wanted to empirically determine if sugar intake could lead to depression. In order to answer this supposition, Anika Knüppel of the UCL Institute of Epidemiology and Health studied data from 8,000 British adults who filled out a questionnaire on their eating habits and lifestyle since the 1980s. This included questions like, “How often do you eat a piece of cake?”
Participants were also asked to complete a mental health survey and were measured for their height and weight. After controlling for variables such as socioeconomic status, researchers found that men whose diets consisted of fizzy drinks, cakes, and sugary teas had a 23 percent increased risk of experiencing an episode of clinical depression or anxiety in the following five years. This pattern was not seen among the women participants -- but this may not be indicative of anything significant. Knüppel noted that among the pooled participants, women consisted of a lesser percentage than that of men. This could be a reason why no relationship between sugar intake and mental illness risk among women was seen.
“I had a feeling we’d see the ‘Bridget Jones-like women eat chocolate’ idea. But it turns people underestimate that men’s sugar intake is super high,” she said. Nonetheless, Knüppel emphasized that women only made a third of the sample size of the study.
Critics of the study suggest that Knüppel calculated her results based on an inherently flawed system. Numbers were taken from a self-tested questionnaire; one that is potentially embarrassing to the survey takers. There could be a level of dishonesty that could skew the results. However, Knüppel countered that is would be “quite unlikely” that participants would exaggerate what they eat. In fact, her results could be distorted, but in the opposite direction. What she could be seeing may actually be a lesser effect than the true representation. Moreover, at least three previous pieces of research support her findings.
Knüppel believes that sugar could affect mood in several ways. One crucial mechanism is neural cell development. She has hypothesized that high levels of sugar reduce the production of a certain protein that regulates neuron growth. The development of mood disorders like depression and anxiety are thought to be involved in this process. Additionally, excessive sugar consumption dramatically increases the amount of inflammation found in the body; a condition, scientists say, that can prompt an episode of mild depression.
Tom Sanders, professor emeritus of nutrition and dietetics at Kings College London, remained cautious about these findings. He says that even controlling for lifestyle habits, other confounding factors can be seen in the analysis of this study.
“From a scientific standpoint, it is difficult to see how sugar in food would differ from other sources of carbohydrate on mental health, as both are broken down to simple sugars in the gut before absorption and the glycemic index of sugar is less than refined starchy foods such as white bread and rice,” he said.
Depression and anxiety are devastating conditions. For those afflicted with the disease, daily life can be extremely hard. For the most part, patients are prescribed harmful synthetic medicine alongside cognitive behavioral therapy. The prognosis for this combination treatment varies, with some people getting better while others steadily fading into a worse state. It can become an incredibly frustrating situation for the ill patient to live normally.
Thankfully, there is a simple solution in sight. Recent studies are validating the efficacy of magnesium in the prevention and treatment of milder forms of depression. In fact, a nutritional study published in PLoS ONE concluded that taking 248 milligrams of magnesium a day led to a reversal of several symptoms of depression. Magnesium was not only more effective, but it was also cheaper in the long run.
It is only recently that mainstream media is acknowledging these claims.
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