• Lung cancer is one of the most common cancers in the world
  • Microbiome positive changes may affect lung cancer progression
  • Yogurt and high-diet fiber consumption nourishes good bacteria in our gut

Introduction – Lung cancer is a condition characterized by an uncontrollable cell division in the lungs[1]. This uncontrollable cell growth leads to tumor which is caused due to somatic changes in the TP53(tumor protein 53), EGFR(epidermal growth factor receptor) and  KRAS( KRAS proto-oncogene) genes, as well as due to many life style and environmental factors such as: smoking, air pollution, asbestos etc. [2],[5]. Cigarette smoking is considered to be the most important cause of lung cancer[3]. It is believed to be responsible for at least 90% of lung carcinoma[3]. The risk of lung cancer is proportional to the length of time and amount of smoked cigarettes[3]. Stopping smoking significantly decreases chances of developing lung cancer[4]. Based on the size of the  affected cells when viewed under microscope, lung cancer is divided into two types:

  1. Small lung cancer, which is believed to arise in the central lung and to have a poor prognosis since it grows quickly and metastasizes commonly to the liver, brain and bones by the time it is diagnosed [5]
  2. Non-small lung cancer, which accounts for 85 percent of lung cancer, and based on the cells it arises it is dived into: adenocarcinoma, squamous cell carcinoma and large cell lung carcinoma[5].
Fig.1 Lung cancer spotted on a chest X-ray. Image taken from [14]

Statistics – Lung cancer is the leading cause of cancer death among men, and the second leading cause of cancer death among women worldwide[6]. Whereas, in the USA is the leading cause of death among both men and women[6]. It is estimated that 142,670 deaths from this disease have occurred in this year[7]. Changes in lifestyle tend to change mortality rates; due to a decrease in smoking,  from 2012-2016 death rates for men have declined by 4 percent each year and 3% for women[7].

Diagnosing and Treatment – There are many clinical features doctor should be looking for in order to diagnose lung cancer[3]. The most common early symptoms are a cough dry and hemoptysis, which are common especially with central bronchial tumors[3]. These symptoms are followed by chest pain, shortness of breath, loss of appetite, tiredness, persistent lung infections etc [8]. Lung cancer is treated in several ways based  on the type of the lung cancer and its staging [9]. People with lung cancer may be treated  differently: with surgery, chemotherapy, radiation therapy, targeted therapy or a combination of these methods[8].

Fig 2. High fiber meal with yogurt. Image adopted from [15]

Latest research – Diet and nutrition recently turn to be very effective in lung cancer prevention since promoting a healthy gut microbiome helps in preserving host’s health[10].
Since the dietary fiber is the main source of prebiotics and a yogurt is a probiotic food, they bestow different health benefits because their consumption feeds healthy gut microbes[10] The healthy gut microbes are a source of short-chain fatty acids that reduce inflammation and strength our immune system after they get absorbed into the blood stream [10],[13]. In order to find out the benefits of a diet high in fiber and yogurt and their association with reduced risk for lung cancer, a study involving 1.4 million adults in the USA, Europe and Asia was done in Vanderbilt University Medical Center[10].According to the amount of fiber they consumed, participants  were divided in five different groups[10]. Data say that people with the highest consumption of fibers had 17% lower risk of lung cancer, whereas people who ate the high amount of yogurt had 19% lower risk to develop lung cancer compared to those that don’t eat it[11]. When consider jointly, people with the highest amount of fiber and yogurt consumption tend to lower their chances of lung cancer by 33%[11],[12].

Conclusion After measuring the dietary fiber intake and yogurt consumption by validated instruments,  we can conclude that high-fiber diet and yogurt consumption are associated with reduced risk of lung cancer. This study proves that prebiotics and probiotics have a potential role against lung carcinoma by modulating gut microbiota in a profitable way.

COPYRIGHT: This article is the property of We Speak Science, a non-profit institution co-founded by Dr. Detina Zalli and Dr. Argita Zalli. The article is written by Rexhep Sahatçiu, University of Prishtina, Kosovo.


1 https://www.medicalnewstoday.com/articles/323701.php

2. http://www.amsa.at/de_DE/activities/stolzalpe/?fbclid=IwAR3q2zzXQzWHdbUH4O2-WxDqCh0zxQSTbc1al7tf2sfyxJ1CKpaUi09jGG8

3. Davidson’s Principles and Practice of Medicine

4 https://www.mayoclinic.org/diseases-conditions/lung-cancer/symptoms-causes/syc-20374620

 5 https://ghr.nlm.nih.gov/condition/lung-cancer#genes

  6. https://link.springer.com/chapter/10.1007/978-3-319-24223-1_1

  7. https://www.cancer.net/cancer-types/lung-cancer-non-small-cell/statistics

 8. https://www.cancercenter.com/cancer-types/lung-cancer/symptoms

 9. https://www.cdc.gov/cancer/lung/basic_info/diagnosis_treatment.htm

 10. https://www.sciencedaily.com/releases/2019/10/191025113010.htm

 11. https://jamanetwork.com/journals/jamaoncology/article-abstract/2753175

 12. https://www.nytimes.com/2019/10/24/well/eat/fiber-and-yogurt-tied-to-lower-lung-cancer-risk.html

13. https://time.com/5236659/best-probiotic-foods/

14.  https://www.webmd.com/lung-cancer/ss/slideshow-lung-cancer-overview

15. https://www.medindia.net/news/high-fiber-yogurt-diet-may-reduce-lung-cancer-risk-191126-1.htm