Almost everyone has heard that high-fat food is bad for the heart. Now, an Australian study suggests that it's also bad for the lungs.
Four hours after eating a high-fat meal, people with asthma showed increased lung inflammation and reduced lung function. They also showed a weaker response to asthma medication.
The researchers are unsure why the high fat meal caused the inflammation. They suggest that the immune system may be recognizing saturated fat as an invading pathogen.
Asthma has been on the rise over the past few decades. One of the many suggested reasons for this increase is the typical high-fat Western diet. Dietary fat has been known to provoke an immune response and raise inflammation in the body, but specific effects in the airway haven't been previously studied, according to the researchers.
The study employed 30 non-obese people with asthma. Half of them ate a high-fat meal while the other half ate a low-fat meal. Sputum samples were collected before the meal and four hours afterward. In addition, lung function was also tested at both of those times.
The high fat meal was fast-food hamburgers and hash browns, weighing in at 1,000 calories. It contained about 50% fat, much higher than the American Heart Association recommendation of 25-35% fat, tops, for a meal. The low fat meal was 200 calories and 13% fat. It was mostly low-fat yogurt.
The researchers are unsure why the high fat meal caused the inflammation. They suggest that the immune system may be recognizing saturated fat as an invading pathogen. They also are unsure how long the effects of the meal might last, but add that if someone is eating high fat food every day, they may be experiencing the effect for several hours daily.
It will take a lot more work to tell just how significant this study is. For one thing, the difference between the high fat and low fat conditions was extreme. The researchers compared the effects of a 1,000 calorie meal to that of a 200 calorie one. A study where both groups consume the same number of calories but different amounts of fat would be more meaningful. But the current study does suggest that asthma sufferers, for whom every breath can be a struggle, might consider eating lower fat meals.