The World Health Organization (WHO) estimates that depression will be the second leading cause of morbidity worldwide by the year 2020 with around 150 million people suffering from the condition. The prevalence of depression is high; with one in seven individuals at a risk of suffering from a depressive episode in their lifetime. There are numerous factors that put you at risk of depression, but the role of diet, especially sugar, is not explored enough. Several studies have linked increased risk of depression with higher consumption of foods rich in added sugars such as soft drinks and juices.
How is sugar linked to depression?
It is a well-known fact that excessive sugar intake puts you at risk for obesity, diabetes and other related diseases. However, the role of sugar in mental health conditions is not much known. Studies have shown that eating a diet rich in refined carbohydrates and sugars is also a common risk factor for depressive illness. Here’s how sugar can put you at risk of depression.
1. High sugar can cause inflammation
A diet rich in refined carbohydrates can provoke inflammatory pathways whereas a diet rich in omega-3 fats and fruits and vegetables may reduce the inflammatory response. Several studies have established the role of inflammatory pathways in depression. Diets, which are high in refined starches, sugar, and saturated fats and poor in natural antioxidants are known to activate inflammatory pathways. There has been a correlation between nutritional intake and the central nervous system plus the immune function which can impact mental health. Hence, it can be stated that diets that promote inflammation can lead to symptoms of depression.
2. Sugar depletes vitamins
Unlike natural sugar, refined sugar (table sugar or added sugar) lacks essential nutrients and only adds up your calorie intake. Moreover, it robs vitamins and minerals obtained through foods. When you eat refined sugar, the body uses stored nutrients to digest it, which may lead to nutritional deficiencies. Studies have shown the link between Vitamin D, Vitamin B (folate and VItamin B12) and magnesium deficiencies and depression. Severe vitamin B12 deficiency causes loss of memory, mental dysfunction, and depression.
For example, a high intake of fructose can increase the expression of an enzyme which is responsible for the degradation of Vitamin D and also impairs the synthesis of this vitamin. This can cause a reduction in Vitamin D levels and in the long run can lead to Vitamin D deficiency. It can also affect the levels of calcium, as Vitamin D is needed for the absorption of calcium.
3. Carbohydrates affect your mood
Carbohydrates are known to play a key role in the functioning of mental health. It is seen to affect mood and behavior. A diet rich in carbs triggers the release of insulin, which aids in the absorption of glucose and also triggers the entry of tryptophan into the brain. Tryptophan, an amino acid, helps in maintaining the levels of neurotransmitters or brain chemicals, which promote the feeling of well being.
Although carbohydrates are needed for overall brain function, choosing the right type of carbs is important. A 2015 study published in the American Journal Of Clinical Nutrition revealed that the quality of the carbs matter and not the quantity. The study showed that women who ate low glycemic index (GI) foods had a lower risk of depression than those who ate high GI foods. This is because, low GI foods provide a moderate but long-lasting effect on the brain function, mood, and energy level. The foods with high GI scores such as sweets contain simple carbohydrates that raise the blood glucose levels quickly and improve mood and energy levels temporarily.
Sugar and depression: Who is at risk?
It is reported that men are at a higher risk of suffering from mental health problems caused due to sugar as compared to women. As per the 2017 study, men who ate around 67g or more of sugar per day were 23 percent more likely to have depression. Men who ate around 40g or less sugar on a daily basis were at a lower risk of depression.
Moreover, according to a research study published in the British Journal of Psychiatry, people who ate processed foods were more likely to be diagnosed with depression five years later than those who consumed whole foods such as vegetables, fruits, and fish. The list of processed foods included foods heavily loaded with sugar such as fried foods, refined grains, sweetened desserts, processed meat, and high-fat dairy products. So load up your plate with fresh fruits and vegetables to lower your risk of depression in middle age.
Tips to cut down on excess sugar
– Read the labels carefully to identify hidden sources of sugar because savoury foods like sauce and even the healthy foods such as yoghurt can be loaded with sugar.
– Cut down your intake of simple sugars which are known to cause a rapid surge in the glucose level and also up the risk of depression. Replace refined sugars with complex carbohydrates such as whole grain.
– Avoid intake of obvious food sources of sugar such as sugar-sweetened beverages, aerated beverages, coffee drinks, energy drinks, smoothies, fruit juices, or lemon juice.
– Choose low GI fruits and foods.
(The article is reviewed by Dr. Lalit Kanodia, General Physician)
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