Increased consumption of fruit, dietary fiber, dairy products and caffeine may be associated with a reduced risk of tinnitus (ringing in the ears), suggests an analysis of the available evidence, published in the open-access journal BMJ Open.

The researchers stress that their findings can’t establish a direct (causal) relationship and should be interpreted with care because of the low quality of the evidence. But they say possible reasons may involve the protective effects of these diets on blood vessels and nerves, as well as their anti-inflammatory and antioxidant properties.

Tinnitus is the perception of sound (ringing, buzzing or clicking) when there’s no external source. Data suggests it affects around 14% of adults worldwide and is associated with depression, anxiety, stress, and in severe cases, suicide.

There is no cure, but treatments such as counseling, behavioral therapy, medications, and hearing aids can help to reduce symptoms.

Diet can also have a significant impact on tinnitus. It’s thought that eating high-quality nutrients can have a positive effect on hearing by improving blood flow to the inner ear and reducing oxidative damage and inflammation. But previous studies show conflicting results and it’s still uncertain which specific foods worsen or relieve symptoms.

To explore this further, the researchers trawled research databases looking for studies linking tinnitus and diet in adults published up to May 2024.

They found eight observational studies involving 301,533 people that assessed 15 dietary factors using validated questionnaires that were of suitable quality to include in their analysis.

The dietary factors included carbohydrates, caffeine, eggs, fruits, fiber, fat, meat, protein, sugar, fish, vegetables and dairy.

The combined findings revealed that increased consumption of fruit, dietary fiber, dairy products and caffeine was associated with a reduced occurrence of tinnitus. These reductions were 35% for fruit intake, 9% for dietary fiber, 17% for dairy products, and 10% for caffeine intake.

No associations were found between other dietary factors and tinnitus and results were consistent after further analyses, although the authors note that the association between caffeine intake and tinnitus remains contentious.

The authors acknowledge that due to the observational design of included studies, causality cannot be established, and the relatively small number of included studies may have led to certain conventionally accepted beneficial dietary factors (such as vegetables and eggs) not demonstrating significant differences.

However, they suggest that “the primary underlying mechanisms may involve the protective effects of these diets on blood vessels and nerves, as well as their anti-inflammatory and antioxidant properties” and say further large-scale studies are needed “to complement and verify the relationship between dietary intake and tinnitus.”