Omega-3 can mitigate asthma

- while omega-6 can aggravate the disease

Omega-3 can mitigate asthmaOmega-3 and omega-6 fatty acids in our diet have opposite effects on the severity of asthma in vulnerable children. Omega-3 appears to reduce the severity of asthma symptoms, while omega-6 seems to make the symptoms worse, according to an article published in the American Journal of Respiratory and Clinical Care Medicine. The problem with modern diets is that they tend to contain far too little omega-3 and far too much omega-6. However, this is something one can correct with help from dietary changes and fish oil supplements.

Omega-3 and omega-6 fatty acids are essential for our health, and we need them from our diet. Both groups of essential fatty acids are structural components of cell membranes and take active part in a host of biochemical functions that control, among other things, our immune system. Science has demonstrated that it is crucial to ensure a proper balance between the two types of fatty acids so the immune defense works properly. On one hand, our immune defense must be able to fight infections and toxins swiftly and effectively. On the other hand, it is vital that it does not overreact, as this causes chronic inflammation, which is the case with asthma and many other diseases.

Many children get too little omega-3 and too much omega-6

Dr. Emily Brigham, who headed the new study, says that there is ample evidence that diet plays a crucial role in respiratory health, and she points specifically to the omega-3 fatty acids that are able to slow down undesirable inflammation. Omega-3 fatty acids are mainly found in oily fish and certain plants, seeds, and nuts.
The omega-6 fatty acids have different functions, and Dr. Brigham explains that they have a pro-inflammatory effect. Omega-6 fatty acids are found in most plant oils, and many people get too much omega-6 from these oils that are included in margarine, junk food, and industrially processed foods.
She also says that many American children eat diets that do not comply with the official dietary guidelines. This is particularly true for children from Baltimore City (Maryland), which is the area from which the study participants were recruited.
In other words, children consume far too little omega-3 and far too much omega-6. Interestingly, there is a higher rate of asthma among children in this area compared with the rest of the United States. Because asthma is a type of inflammation, Brigham wanted to take a closer look at omega-3 and omega-6 and how these essential fatty acids affected the children’s asthma symptoms, including their reaction to indoor particle exposure, which can aggravate their symptoms.

Study result: Too much omega-6 increases the risk of inflammation

135 children in the age group 8-12 years took part in the study. All participants had asthma. 96 of the children were Afro-American, and 53 percent were male. Around a third of the children had mild asthma, another third had moderate asthma, and the last third had severe asthma.
Brigham and her team of researchers noted the diet habits of the children, just like they registered their asthma symptoms and their medicine consumption at regular intervals over a six-month period. During the same period, the scientists measured levels of two different particles, PM2.5 and PM10, which are found indoors and are able to trigger asthma. The particles are tiny and not visible to the human eye. Nonetheless, PM2.5 is able to penetrate the small alveolae of the lungs, while PM10, which is a larger particle, can coat the respiratory tract after being inhaled.
The study demonstrated that the children that consumed the highest quantities of omega-6 had elevated levels of neutrophil granulocytes, which is a type of white blood cell that is associated with inflammation. The scientists recognize that the study results have certain limitations, as the intake of omega-3 and omega-6 fatty acids were self-reported. Helped by their parents, the children filled in questionnaires.
Because this is not a randomized, controlled study, the researchers were unable to prove a causal effect, and they were unable to rule out other factors that could have affected the children’s asthma. Nonetheless, the scientists assume that the study results point to the potential role of diet in the development and severity of asthma. Subsequently, they suggest that eating a healthier diet may protect asthmatic children against different harmful particles in the indoor climate.

Earlier studies confirm that omega-3 protects against asthma

The new study is backed up by earlier studies where scientists have demonstrated that too much omega-6 increases the risk of developing asthma. In contrast, the two omega-3 fatty acids, EPA and DHA, that are found in oily fish and fish oil supplements lower the risk of developing the disease.
Expecting mothers who eat oily fish several times per week or take fish oil supplements can also
protect their offspring against developing asthma later in life, according to two studies from University of South Florida in Tampa, USA.
It is also important to make sure that the dietary content of omega-3 and omega-6 fatty acids has the right balance. One can easily get enough omega-6, whereas it is more challenging to get the right amount of omega-3, so high-quality fish oil supplements may be worth considering.

Omega-3 sources:

  • ALA (alpha-linolenic acid): Linseed oil (in particular) and rapeseed oil, walnuts, and certain leafy greens
  • EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid): Mainly oily fish, fish oil, cod liver oil, and shellfish

Important note: Many people have difficulty with converting ALT into the active forms, EPA and DHA

Omega-6 sources:

  • LA (Linoleic acid): Most plant oils from e.g. thistle, sunflower, corn, grape, and margarine.
  • GLA (Gamma-linolenic acid): Borage, evening primrose, oats, blackcurrant, breast milk.
  • AA (Arachidonic acid): Meat, fish, liver and other types of offal, dairy products.

Why do many of us get too much omega-6 and too little omega-3?

There are many factors involved. Animal fodder with high quantities of omega-6, altered diets with less fish, more ready meals, margarine, and deep-fried foods contribute to our high omega-6 intake and limit our omega-3 consumption. Western diets often contain omega-6 and omega-3 in a 10:1 ratio. In some cases, the ratio is 30:1. The optimal omega-6/omega-3 ratio is believed to be 4:1 or lower.

References:

Emily P Brigham et al. Omega-3 and Omega-6 intake Modifies Asthma Severity and Response to Indoor Air Pollution in Children, American Journal of Respiratory and Clinical Care Medicine. 2019

American Thoracic Society. Omega-3 and omega-6 fatty acids may play opposite roles in childhood asthma. ScienceDaily. 2019

Shahieda Adams et al. Relationship between Serum Omega-3 fatty Acid and Asthma Endpoints. Int J Environ Res Public Health. 2019

Chen Hsing Lin, Richard F. Lockey. Prevention of Asthma: Fish or Fish Oil? The Journal of Allergy and Clinical Immunology: In Practice, 2017