There is not much information available on foods that have a bad effect on the lungs. However, there are a range of foods that cause other diseases and these may also be harmful for respiratory health.
High salt diets may increase the risk of asthma or exacerbations in adults with asthma.
Although the evidence for the effect of salt on lung function in not concrete, controlling salt intake is a sensible step.
The recommended daily allowance for salt is 5–6 g per day.
Over the last 15 years, there have been changes in the types of fat that we consume in developed countries. In particular, our intake of dietary omega-6 fatty acids (corn and sunflower) and trans-fatty acids (fried foods and margarine) has increased, while our intake of saturated fats (butter and lard) and omega-3 fatty acids (salmon and sardines) has decreased.
This change in fatty acid consumption may play a role in the development of allergies in children and an increased risk of asthma.
Therefore, intake of omega-6 and trans-fatty acids should be kept to a minimum.
Levels of obesity are rising in both the developed and developing world.
Obesity may increase the incidence of asthma and airway hyperresponsiveness. In addition, if someone is obese then their lung function is decreased.
Weight reduction could improve symptoms, airway hyperresponsiveness and lung function.
Some common food additives may cause exacerbations of asthma, including tartarzine, monosodium glutamate (MSG) and sulphites.