It is often said that what you eat affects your mood. But, can eating certain food help to reduce the risk of mood disorders such as depression? A study has found a handful of nuts can cut down the risk of depression by 17%.

Researchers analyzed data from around 13,000 people, with an average age of 58 years, from the U.K. Biobank, a large-scale biomedical database. The participants did not have depression at the start of the study. Using questionnaires, the nut intake and symptoms of depression or use of antidepressants in the participants were noted.

The findings of the study were published in Clinical Nutrition.

"Low-to-moderate nut consumption (>0 to 1 serving of 30 g/day) was associated with a 17% lower risk of depression during a 5.3-year follow-up compared with no nut consumption in a large sample of middle-aged and older UK adults. This protective association is enhanced in the absence of other known risk factors for depression," the researchers wrote.

They believe the protective effect of nuts comes from anti-inflammatory and antioxidant properties, although the study has not done a causative analysis.

"These nutrients prevent inflammation throughout the body, including the brain. Researchers believe that inflammation in the brain is the cause of many illnesses, such as dementia and depression. This study shows a correlation between nut consumption and lower incidences of depression, but it does not show causation," Natalie Rizzo, a registered dietitian who was not involved in the study, said.

Some experts believe the amino acids present in the nuts, such as arginine, glutamine, serine and tryptophan, provide the benefits as reduced levels of amino acids have links with depression.

Here are some of the health benefits of nuts:

1. Heart health - Consumption of nuts is associated with reduced levels of LDL cholesterol and triglycerides in the body. When the cholesterol levels are reduced, it in turn reduces the risk of coronary heart disease and myocardial infarctions.

2. Weight loss - Studies have shown that although nuts are generally high in calories, they can help in weight loss. This is because all the calories in the nuts are not absorbed by the body.

3. Control diabetes - Research has shown that individuals with type 2 diabetes and metabolic syndrome have improvements in their health indicators like blood sugar levels and blood pressure when nuts are included in the diet.

4. Rich source of nutrients and fiber - Nuts contain several essential nutrients, including vitamin E, magnesium, selenium and fiber. High fiber in nuts such as almonds, pistachios and pecans can improve gut health and reduce the risk of developing diseases.