London - Eating white bread and rice could increase the risk of depression in older women, research suggests.
But whole grain foods, roughage and vegetables could reduce it.
Refined foods cause blood sugar levels to spike rapidly – prompting the body to pump out the hormone insulin, which helps break down the sugar. But this process can cause symptoms of depression, according to the study.
The findings, published in The American Journal of Clinical Nutrition, could pave the way for depression being treated and prevented using nutrition.
In a study that included data from over 70 000 post-menopausal women, scientists found a link between refined carbohydrate consumption and depression.
When people eat carbohydrates their blood sugar levels rise to varying degrees.
The glycaemic index (GI) scale of 1-100 measures the amount of sugar found in the blood after eating.
The more highly refined the carbohydrate, the higher its score on the GI scale.
Refined foods such as white bread and white rice trigger a hormonal response in the body to reduce blood sugar levels. The response may also cause or exacerbate mood changes, fatigue and other symptoms of depression.
A clear link between high GI scores and consumption of added sugars and refined grains were associated with increased risk of depression in the women.
Diets packed with dietary fibre, whole grains and vegetables led to a decreased risk.
The researchers said further study was needed to examine the potential of this novel option for treatment and prevention, and to see if similar results will be found in the broader population.
Study author Dr James Gangwisch of Columbia University, said: “This suggests dietary interventions could serve as treatments and preventive measures for depression. Further study is needed to examine the potential of this novel option for treatment and prevention, and to see if similar results are found in the broader population.”
White refined foods, known as “bad carbs” have also been said to contribute to obesity, low energy levels and insomnia.
Different from their healthier counterparts, white carbs start with flour that has been ground and refined by stripping off the outer layer where fibre is found.
This missing fibre could do wonders for the body, helping reduce the risk of type 2 diabetes, lower blood cholesterol and help people feel fuller for longer.
Generally, the more refined the grain-based food, the lower the fibre count.
Daily Mail