This is the second of a four part blog series that was taken from a research paper published by Dr. Mark Dedomenico, Director of The Hope Heart Research Institute. In this series Dr. Dedomenico discusses what makes up the immune system, how to evaluate your immune system, what weakens your immune system, and how to strengthen your immune system.
The first line of defense is to choose a healthy lifestyle. Every part of the body functions better when bolstered by healthy-living strategies. The following lifestyle behaviors have been proven to weaken the immune system.
- Sedentary: Most people do not have a physically active lifestyle, which is one of the most important builders of the immune system. Regular moderate intensity exercise is beneficial for improving cardiovascular health, lowering blood pressure, and controlling body weight, all of which help to boost the immune system.
- Diet/Obesity: We have gone from eating basic fruits, vegetables, nut, meats, eggs, fish, and whole grains to a diet full of ultra-processed foods, sugar, and other nutrient poor food which creates systemic low-grade inflammation. An unhealthy diet prevents people from getting the necessary micronutrients and Omega-3 fatty acids. This impairs the production and activity of immune cells and antibodies. A Western diet high in refined sugar and red meat and low in fruits and vegetables can also promote disturbances in the healthy intestinal microorganisms, resulting in chronic inflammation of the gut, and associated suppression of the immune system.
Studies have also proven that excess body fat causes inflammation, which weakens the immune system. Most of those who had a severe illness from COVID-19, had excess body fat and/or a chronic metabolic condition. Today’s diet results in weight gain and a population in which over 50% of people are obese, super-obese and morbidly obese. Twenty-five percent of the population is overweight. As we age, the overweight/obese inflammation becomes worse. This makes people over age 60 have more inflammation of their gut.
- Stress/Anxiety/Depression: Stress releases cortisol which normally is anti-inflammation However, chronic cortisol release is inflammatory and leads to weakening of the immune system.
- Poor Sleep: Sleep is a time of restoration for the body, during which a type of chemical called cytokine is released that fights infection. Too little sleep lowers the number of cytokines and immune cells. Studies show that people who don’t get quality or enough sleep are more likely to get sick after being exposed to a virus. It can also affect how fast someone recovers if they do get sick.
- Metabolic Disorders: Hypertension, diabetes, high cholesterol, and many other metabolic disorders cause inflammation, to which the immune system sends groups of cells to fight, thereby weakening the immune system.
- Smoking: Smoking causes lung inflammation that demands cells from the immune system while creating excess secretions throughout the lungs, a perfect environment for pathogens.
- Alcohol: Directly suppresses the immune system.
To continue reading How to Evaluate your Immune System click here. Other posts in this blog series include What is the Immune System and How to Strengthen your Immune System. We have also added an immune system FAQ you may read by clicking here.
Written by: Dr. Mark Dedomenico, Director of The Hope Heart Research Institute and CEO and Owner of PRO Club and PRO Medical.

Dr. Mark Dedomenico, a former cardiovascular surgeon, played a key role in developing the procedure known as Coronary Bypass Surgery along with Dr. Lester Sauvage. Working together as two of the initial founders of the Hope Heart Institute, they also created some of the most significant developments in heart surgery. These included the creation of artificial heart valves and Bionit arterial grafts used to replace damaged or atherosclerotic arteries. Dr. Dedomenico’s work has also taken him into the areas of genetics, nutrition, exercise physiology, and behavior modification.
In 1992, Dr. Dedomenico began a new research project devoted to the treatment of early stage metabolic disease to prevent individuals from later needing cardiovascular surgery or medications to control hypertension, high cholesterol and diabetes. The research led to the creation of the 20/20 LifeStyles program. In 2002, 20/20 LifeStyles was selected as a credentialed provider of Microsoft’s weight-management program.
Dr. Dedomenico’s research and work with 20/20 LifeStyles remains ongoing and prevalent. He has formulated successful long term treatment methods of obesity, hyperlipidemia, hypertension, diabetes, depression, fibromyalgia, binge eating disorders and arthritis. Additionally, Dr. Dedomenico is currently involved in a major osteoarthritis research project in conjunction with Colorado State University. He is devising new methods to control, prevent and stop the disorder.
In addition to his experience as a practicing surgeon, Dr. Dedomenico spent many years overseeing one of the country’s largest and most respected privately-held companies, Golden Grain Macaroni Company, the producer of many well-loved consumer products, including Rice-a-Roni, Mission and Golden Grain pasta, Ghirardelli chocolates, and Vernell candies.