While inflammation may not be the root cause the body will manifest itself with increased levels of inflammation. Depression may not be caused by inflammation but it manifests in the body as inflammation. So while many strategies can be used, like cognitive behavior therapy to treat depression, you will also need to treat the underlying inflammation. The same applies to every form of chronic illness. So it important to understand some of the key factors that can increase inflammation.
Common causes of inflammation include:
obesity and extra weight
physical inactivity or too much activity
chronic infection including periodontal disease
vitamin D and other nutrient deficiency
toxins such as heavy metals and pesticides
prescription and over-the-counter drugs
And while these act independently many of them are also associated with each other. For example, poor nutrition increases the risk of obesity, poor gut health, stress, sleep problems and vitamin D deficiency.
Western diet link
Numerous studies have now reported that the typical modern Western diet is closely linked with higher levels of chronic inflammation (1) and our modern diet is high in foods that provoke inflammation, such as refined flour, excess sugar and carbohydrates, acrylamide, oxidised (rancid) fats, red meat and animal saturated fats, omega 6 fatty acids (vegetable oils and especially margarine), trans fats, and a wide range of chemicals, preservatives and alcohol (2,3). The modern Western diet is also low in foods that reduce inflammation, like long-chain omega-3 fats, fermented foods, prebiotics and anti-inflammatory nutrients.
Carbohydrates including white breads, pastas and sugar-rich diets are also linked with inflammation (4).
Acrylamide is found in heat-treated, carbohydrate-rich foods like potato chips and breakfast cereals and long term ingestion lead to high rates chronic inflammation (2). Carbohydrates including white breads, pastas and sugar-rich diets are also linked with inflammation (4). In a study of overweight adults, a sugar-rich diet, typical of our Western processed diet, for 10 weeks resulted in significant increases in inflammation (5) . In another study of middle aged, healthy, women, a high GL diet was shown to be associated with higher levels of inflammation (6) , while a larger study reported that a high glycemic index diet was associated with a small but significant increase in inflammation in more than 18,000 middle to older aged women (7).
Omega 6 fatty acids
Of particular concern in our modern diet is the rapid increase in the use of pro inflammatory omega 6 fatty acids.
Vegetable oils (Canola, Sunflower, Corn, Safflower, Grapeseed, Rice Bran and Soybean), which are made from seeds not vegetables, and margarines are rich in omega 6 oils. Omega 6 oils are also found in caged and factory poultry and eggs, meat from feedlot cattle and farmed fish (from the omega 6 - rich oil they are fed). A diet disproportionately high in omega-6 fatty acids, which are commonly used in the production of processed foods, increases inflammation (8,9). Omega 6 PUFAs, has been linked with increased tumour growth and enhancement (10) including cancers of the colon, breast, and prostate. Trans fats contained in hard margarines, as well as french fries, beef and milk fat, are one of the leading causes of chronic inflammation and can be commonly found in Western food(11).
Over consumption of animal-based saturated fats (palmitic and stearic acid are found in higher concentrations in meat) has repeatedly been shown to be linked with inflammation. In 2008, a study of volunteers eating a breakfast rich in butter, consisting of 35% saturated fats, like a typical Western diet, experienced increases in inflammation (12). While in a large British study (Whitehall II) higher saturated fatty acid levels in the blood were associated with higher inflammation (CRP and fibrinogen) (13).
The studies suggest that saturated and trans-fat intake may influence inflammation, at least in part, via the health of the gut.
Many studies have linked animal protein with adverse effects on chronic disease including CVD and cancer. The majority of scientific results were positive and can be explained by a number of factors such as carcinogenic substances, mechanisms of inflammation in the colon, oxidative stress and lipid peroxidation (fat oxidation). Meat appears to increase inflammation through its effect on the gut microbiome. Many farmed meats may now also be high in omega 6 oils. In addition, chemicals found in cooked meats which may contribute to inflammation and oxidation including Heterocyclic Aromatic Amines (HAAs), Polycyclic Aromatic Hydrocarbons (PAHs) and N-nitroso compounds (NOC). These contribute to carcinogenic effects because they are involved in mechanisms of inflammation and oxidative stress.
Obesity and inflammation
Over the last decade, an abundance of evidence has emerged demonstrating a close link between obesity and inflammation with significantly higher levels of inflammation in obese people, while, on the other hand, weight loss is associated with a decrease in inflammation (15). Obese individuals have a high circulating levels of a range of inflammatory markers produced by adipose tissue. It is now clear that obesity is associated with a state of chronic low-level inflammation which explains why many overweight/obese people suffer from co-morbid conditions such as arthritis, insulin resistance, type 2 diabetes, atherosclerotic heart disease and cancer.
Obesity is the result of an accumulation of adipose tissues commonly referred to as body fat. Traditionally, adipose tissue was believed to be a simple depository of accumulated excess calories in the diet. However, recent studies into white adipose tissue or ‘WAT’ (main site of long term storage of fat in the body) led scientists to discover that fat is a complex and multifaceted organ system (16). The usual production sites of inflammation are the liver and the lymphoid organs but, in obesity, WAT is converted as the major producer of inflammation (17).
Additionally, in obese persons, the adipose cells have the incredible capacity to increase their diameter 10 to 15 fold (18) resulting in greater chronic inflammation. To put this in perspective, the expression of one of the inflammatory markers, IL-6, in adipose tissue from obese individuals is 10 times that in adipose tissue from lean individuals. In obese individuals, adipose tissue is a major determinant of plasma IL-6 concentrations, contributing as much as 30% of total body production. Inflammation has also been identified with childhood obesity (19).
Most chronic inflammation in the body originates in the gut either directly or indirectly since around 70% of the immune system is located in the gut.
Most chronic inflammation in the body originates in the gut either directly or indirectly since around 70% of the immune system is located in the gut. This occurs firstly though the processing of inflammatory foods such as omega 6 fatty acids, its direct influence on the immune system, and the influence gut dysbiosis. A healthy gut microbiome is essential to reduce inflammation.
Stress-induced inflammation has been implicated in several major disorders, including cardiovascular disease, depression and even increased ageing and mortality. Research has shown that psychosocial stress stimulates inflammation (20). Studies have shown chronically negative relationships foster low-grade systemic inflammation, which then contributes to the evolution and/or expression of psychiatric, infectious, metabolic, and coronary diseases.
A study of married couples who had higher levels of conflict and hostility in the laboratory, showed higher levels of the inflammation the next morning (21).
Lingering effect of childhood trauma
In addition, evidence from animal and human studies has suggested that early exposure to trauma in childhood may increase the subsequent risk of poor functioning of the immune, hormone and nervous systems. In a longitudinal study following 1,000 participants from birth to 32 years of age, individuals experiencing stress in childhood resulting from maltreatment, abuse, social isolation and economic hardship were twice as likely to suffer chronic inflammation (22).
Interestingly, while exercise initially produces inflammatory cytokines it quickly suppresses a broad inflammatory response and mediates the beneficial effects of exercise. This is known as a hormetic effect, where an initial stressor provokes a compensatory response in the body that has positive, long-term consequences.
In direct contrast, sedentary behaviour increases inflammation (23).
In a study with 4757 participants independent of potential confounders, including moderate-to-vigorous exercise, sedentary time was associated with increased inflammation (24).
Chronic sleep loss has also been shown to increase inflammatory markers even in people that are otherwise healthy. Both chronic and acute sleep deprivation are associated with enhanced inflammation. Even acute sleep deprivation results in impairments in immune functioning, characterised by increased levels of inflammation (25).
Chronic infections produce ongoing inflammation and while all types of chronic infections lead to increased inflammation the most studied are dental caries and periodontal disease. Periodontal disease is also a significant predictor of other inflammatory illnesses, such as CVD, and health outcomes, such as mortality in diabetes and coronary artery disease (26). Other chronic illnesses might include hepatitis and herpes or even wounds that fail to heal, including ones infected with antibiotic resistance bacteria.
Vitamin D crucial
There is no doubt that low levels of any essential nutrients is likely to increase inflammation, but none more than Vitamin D.
Low levels of Vitamin D, particularly 25-hydroxyvitamin D are widespread among Western populations, making it the most prevalent deficiency state. Low Vitamin D is linked to a diversity of adverse health outcomes, such as osteoporosis, cancer and multiple sclerosis. Vitamin D is involved in controlling immune responses to infection, including directly reducing inflammation (27) . Supplementation with vitamin D has been shown to reduce inflammatory markers. In human studies, supplementation with Vitamin D reduces inflammation in people with cystic fibrosis and multiple sclerosis and slows down disease progression (28).
The liver breaks down most of the alcohol a person consumes only to produce toxins even more harmful than alcohol which promote acidosis, oxidation and inflammation. The good news is that a single drink of alcohol a day (around 40g/d) seems to lower levels of CRP. However, too much alcohol has the opposite effect. It appears that alcohol shows a J shaped inflammation response whereby a small amount (1-7 glasses per week but not all at once) has a beneficial impact on inflammation. The effects are more marked for men compared to women and wine is marginally better than beer (29).
Various toxic compounds trigger an abnormal inflammatory response directly or indirectly through interfering with normal functioning of cells or tissues (30). This includes toxins from cigarettes, pesticides, including herbicides and insecticides, air pollution, heavy metals and persistent organic pollutants. Cigarette smoke contains many thousands of chemicals, including free radicals, metals, tars and other substances that increase inflammation.
The message is very clear. If you want to reduce your illness you need to reduce your inflammation. To do this we need to take action on the major causes of inflammation in our own lives and see where we can lower it. But only if you want to live a longer, happier life.
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Read Part One at http://novaholisticjournal.com/stories/understanding-inflammation
DISCLAIMER: Dr Peter Dingle is a researcher, educator and public health advocate. He has a PhD in the field of environmental toxicology and is not a medical doctor.
Dr Peter Dingle (PhD) has spent the past 30 years as a researcher, educator, author and advocate for a common sense approach to health and wellbeing. He has a PhD in the field of environmental toxicology and is not a medical doctor. He is Australia’s leading motivational health speaker and has 14 books in publication.