Research Update: Omega-3s and Lung Function

Lung function declines as we age; depending on how we treat our lungs, our habits can determine the rate of decline. Working in toxic situations (or even worse, smoking cigarettes) can accelerate the decline. That’s why a recent study that examined blood levels of omega-3 fatty acids and measures of lung function found that our diet has an impact on lung function. Let’s look at this study.

Increases in Omega-3 Levels Prevent Decline

Of the two studies reported in the paper, I’ll stick to the longitudinal study, although both demonstrated the positive impact of omega-3s on lung function. A couple definitions first.

• Forced expiratory volume 1 (FEV1) is the amount of air that one can forcefully breathe out in one second. The normal range is 2,500 to 3,250 milliliters.

• Forced vital capacity (FVC) is the amount breathed out after a normal exhalation. The normal range is 3,700 ml to 4,800 ml.

One more thing: in this study, the mean rate of lung function decline was 36.8 mL per year for FEV1 and 35.8 mL per year for FVC.

Researchers examined a pooled group of studies that were part of the National Heart, Lung, and Blood Institute Pooled Cohorts Study. Studies were chosen because of the repeated measurements of both lung function and plasma phospholipid omega-3 fatty acids. The study found that higher omega-3 fatty acid levels were associated with less decline in lung function for 15,063 participants. The omega-3 that provided the most benefit was the omega-3 fatty acid DHA. In plain English, the more the DHA levels increased over time, the more the decline in lung function was prevented. I know that sounds funny to say it “prevented decline” but to say that it improved lung function would be incorrect.

The Questions

In both studies, nutritional information wasn’t collected, or if it was collected, it wasn’t used in the statistical analyses performed. The assumption seems to be that seafood and plants were the primary sources of omega-3 fatty acids, and that may be true. But it raises a question about the potential for using omega-3s in dietary supplements. Would the same response occur in reducing the risk of chronic kidney disease as it did for the loss of lung function?

It also raises another question. Many studies on the benefits of omega-3 supplements on heart health and other organs are often less than overwhelming. Could it be that there is a nutrient or nutrients in fish that, together with omega-3s, could contribute to benefits? Or could it be there’s a factor that helps with digestion, absorption, and utilization in the actual form of omega-3s used as supplements? We don’t know at this time.

The Bottom Line

While the benefits of omega-3s, specifically DHA, were small, the fact that they prevented decline over years contributes to aging with a vengeance. I think having a diet that includes the regular intake of fatty fish is the key to a healthy lifestyle, and I still think regular use of fish oil supplements may prove to be beneficial as the research continues. I’ll keep you posted.

What are you prepared to do today?

        Dr. Chet

References:
1. Am J Respir Crit Care Med. 2023 Jul 20. doi: 10.1164/rccm.202301-0074OC
2. BMJ 2023;380:e072909. doi: 10.1136/bmj-2022-0729092