Immune system is your body’s defense against infections and other harmful invaders.
When your immune system doesn’t work the way it should, it is called an immune system disorder. You may:
- Be born with a weak immune system. This is called primary immune deficiency.
- Get a disease that weakens your immune system. This is called acquired immune deficiency.
- Have an immune system that is too active. This may happen with an allergic reaction.
- Have an immune system that turns against you. This is called autoimmune disease.
Immunologic problems are consistently demonstrated in both under and overweight, in a poor diet or in malnutrition by excess.
Recent studies in humans and animal models affected by obesity demonstrate an impaired immune response leading to increased chances for various infections and low response to the effects of vaccines. The cause of this has not been well-defined but, according to it, obesity itself has been shown to damage the body defenses; so even if the obese person eats healthy and exercises, is still at risk for decreasing immune function as long as there is not weight control. Some of these specific internal findings included:
- Decreased cytokine production
- Altered monocyte and lymphocyte function
- Natural killer cell dysfunction
- Reduced macrophages and dendritic cell function
- Decreased response to antigen/mitogen stimulation
All those very scientific medical words are just saying that an obese person has all the cells and structures that defend the body reduced in number or in function; they also have an increased inflammatory response involved in promoting heart disease and other illnesses associated with obesity. So the protection is lower than in a normal weight person. Obesity is an extremely complex disease and many processes and pathways are altered, any of which could affect the immune system.
Despite of your weight, a bad nutrition like diets high in sugar and fat, or eating too many calories in general, makes you more prone to infection. This is because it can lead to increases in blood sugar or may cause Oxidative Damage, which is an overproduction of reactive oxygen species compared to the body’s ability to detoxify cells. Human language: your body produces more garbage(toxins) than its capacity of cleaning. More of this “garbage” inside increases your chances of infection.
Garvan scientists in Australia showed for the first time back in 2010 that even modest weight loss reverses many of the damaging changes often seen in the immune cells of obese people, particularly those with Type 2 diabetes. So strengthening the defenses was added among the benefits of reducing body mass index.
But this is not all about the weight. If you have too little protein intake, you are also at risk for protein-energy malnutrition associated to a significant impairments of immunity. Historically it was commonly thought that deficiencies or malnutrition cannot happen in an individual affected by obesity (as when you still see all those moms wanting a fat baby thinking on that as a sign of health); however, deficiencies and malnutrition happen because of a poor diet; therefore, could very well occur in any individual who eats poorly unhealthy not balanced food , no matter the weight.
Worldwide, about 2 billion people are affected by micronutrients deficiencies, including vitamins A, C and E, and the minerals zinc, iron and iodine. Micronutrients deficiencies have effects such as poor growth, impaired intellect, and increased mortality and susceptibility to infection. The group of diseases that have been increasing in the latest 10-15 years due to junk food, fast food, chemically harvested products, bad regimes due to the rush of our daily life and in general a bad global dietary change, is overwhelming.
Beyond any scientific fact, we all can relate the importance of keeping a healthy diet and an adequate nutritional status, with a well-functioning body defenses.