Can a high sugar diet cause depression?
Many of us reach for a chocolate bar, cookies or even a cup of sweet tea when we are feeling a little low. It seems that although this might make us feel good at that moment, doing this regularly over time may instead leave us feeling permanently low!
We are starting to discover several links between diet and mental health and the effects of high-glycaemic carbohydrates have recently fallen under the spotlight. A recent study on post-menopausal women suggests a link between consuming a diet that is high in refined carbohydrates and the risk of suffering from depression.
In their discussion, the study's authors explore various ways in which refined carbohydrates might bring on depression. One way is through the hormonal responses that are triggered when we consume a meal that is high in refined carbohydrates. Simple carbohydrates raise the sugar level in our blood very quickly and sugar triggers insulin release. Insulin removes sugar from the blood and pushes it into cells. Sharp rises in insulin after sugar-heavy meals can leave our blood with very low sugar levels and this reduces glucose supply to the brain. This reduction of glucose supply in the absence of an alternative fuel source can cause irritability, low mood and even cognitive impairment. Repeated spikes of glucose may even affect blood-to-brain glucose transport. Refined sugar also has an inflammatory effect on our bodies and inflammation is thought to have a strong relationship with depression.
Although the study looked at post-menopausal women, the results of this study may well apply to the rest of the population and cutting out added sugar and reducing refined carbohydrates in the diet may reduce our risk of suffering from depression.
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