Introduction
Inflammation is a reaction designed to protect us after an injury or infection. The term owes its origin to the Latin word inflammare, which means “to set on fire.” In the classic response to injury or infection, the injured area becomes red, swollen, hot, and painful. But there is another type of inflammation that is not so obvious. This silent inflammation reflects an underlying low-grade stimulation of the inflammatory process with no outward signs of inflammation. The only time that it becomes apparent is when the blood is tested for markers of inflammation such as C-reactive protein (discussed in detail below). Silent inflammation is a major factor in the development of virtually every major chronic degenerative disease, including cardiovascular disease, allergies, type 2 diabetes, cancer, and Alzheimer’s disease.
There are many factors that trigger silent inflammation, including insulin resistance, obesity, emotional stress, environmental toxins, low antioxidant intake, increased exposure to free radicals (from, e.g., radiation or smoking), chronic infections, imbalances of dietary fats, and increased intestinal permeability.
Markers of Inflammation
The most common test to measure silent inflammation is a blood test for C-reactive protein (CRP).1,2 Technically, CRP is classified as an acute-phase protein. Its physiological role is to bind to the surface of dead or dying cells (and some types of bacteria) in order to activate the complement system, a system of other blood proteins that go on to help destroy the cell, bacteria, or other particulate matter.
In an acute infection or injury, levels of CRP rapidly increase within 2 hours and reach a peak at 48 hours. When the acute inflammation is dealt with effectively, the CRP declines rapidly. Because there are a large number of conditions that can increase CRP production, an elevated CRP level does not diagnose a specific disease. But it does tell us how much inflammation is occurring in the body. Rapid elevations in CRP as high as 50,000 times the normal value of 1 mg/l can occur with inflammation, infection, trauma, tissue necrosis, malignancies, and autoimmune disorders such as rheumatoid arthritis.3
Interest in measuring CRP is the result of significant research showing it to be a very sensitive marker for the prediction for cardiovascular disease.1,2 Indeed, of all the current inflammatory markers used in clinical practice, CRP provides the most conclusive information with regard to cardiovascular risk. Results are typically divided into three different risk categories: low risk (<1 mg/l), average risk (1–3 mg/l), and high risk (>3 mg/l).
Patients with high CRP concentrations are more likely to have a stroke or heart attack or to develop severe peripheral vascular disease. Research also indicates that elevations of CRP are linked to diabetes, some forms of cancer, Alzheimer’s disease, and many other chronic degenerative diseases. Though other candidates for measuring silent inflammation may emerge, there is no question that measuring CRP is the most well-recognized assessment. The best determination is referred to as high-sensitivity CRP (hsCRP), as this test gives results in 25 minutes with a sensitivity down to 0.04 mg/l.
Therapeutic Considerations
There is little doubt that diet is a major contributor to silent inflammation. First, diet is the major contributor to the development of insulin resistance. Decreased responsiveness of body tissues to insulin leads to elevations in blood sugar and increased oxidative (free radical) stress. CRP levels generally parallel insulin resistance. Insulin resistance is largely the result of increased abdominal obesity and excessive consumption of calories, particularly carbohydrates. In fact, abdominal obesity is the strongest independent predictor of silent inflammation and CRP levels.4,5 Therefore, the guidelines given in the chapter “Obesity and Weight Management” should be regarded as the first step in reducing silent inflammation in overweight or obese individuals.
In addition to weight loss, a diet low in refined carbohydrates and starchy foods that can raise blood sugar levels (i.e., a lowglycemic-load diet) is critical in reducing silent inflammation. In a study of more than 200 apparently healthy women, glycemic load was found to be significantly and positively associated with CRP levels.6
In addition to a low-glycemic diet, the Mediterranean diet has also been found to be of great benefit in lowering CRP levels.7 A diet rich in plant pigments, especially flavonoids, found in soy, apples, berries, and other fruits and vegetables, is associated with lower CRP levels as well.8,9
The ratio of omega-3 to omega-6 fatty acids is also a major factor in determining the degree of silent inflammation and CRP levels. The typical Western diet promotes inflammation because it is particularly high in sources of the omega-6 fatty acid linoleic acid and low in sources of both short-chain (alpha-linolenic acid) and long-chain omega-3 fatty acids (EPA and DHA).10 The last 150 years have seen a dramatic increase in foods high in omega-6 fatty acids along with a dramatic decrease of foods rich in omega-3 fatty acids. As a result, the ratio of omega-6 to omega-3 in the Western diet ranges between 15:1 and 20:1—far different from the nearly 1:1 ratio that humans evolved with.
Both omega-6 and omega-3 fatty acids are utilized by the body as building blocks for mediators of inflammation. It is simplistic, but still fairly accurate, to say that most mediators formed from omega-3 fatty acids are anti-inflammatory, while those derived from omega-6 are pro-inflammatory.11 Particularly pro-inflammatory is the omega-6 fatty acid arachidonic acid, which is found in animal foods but also can be formed from linoleic acid. So in fighting inflammation it is a good idea to eliminate common sources of linoleic acid such as soy, safflower, sunflower, and corn oil. The bottom line is that to reduce inflammation there must be a reduced intake of omega-6 fatty acids combined with an increase in omega-3 fatty acids. Ultimately, the goal is to improve the composition and function of the cell membrane. To accomplish this goal, observe the following dietary guidelines:
• Be aware of the fat content of foods. Limit total dietary fat intake to no more than 30% of calories consumed (400–600 calories a day from fat, based on a standard 2,000-calorie-a-day diet). Reduce the amount of saturated fats and total fat in the diet. In general, animal products are high in fat, while most plant foods are very low in fat. While most nuts and seeds are relatively high in fat, the calories they supply come mostly from monounsaturated fats.
• Reduce the intake of meat and dairy products from corn-fed animals while increasing the intake of fish. Particularly beneficial are cold-water fish such as wild salmon, mackerel, herring, and halibut because of their high levels of omega-3 fats.
• Cook with olive, canola, or macadamia nut oil. Use flaxseed oil or olive oil as your base in salad dressings.
• Eliminate margarine and other foods containing trans-fatty acids and partially hydrogenated oils.
• Take a high-quality fish oil supplement providing at least 1,000 mg EPA + DHA daily.
Physical activity is tightly linked to inflammation in a very complex manner. It does not appear to affect CRP, but rather affects other markers of silent inflammation such as interleukins. Regular, moderate exercise reduces the level of silent inflammation, while high-intensity training for a prolonged period increases silent inflammation.12–14
Increased permeability of the intestinal lining can be the result of food allergies, microbial toxins, food and environmental toxins, some drugs such as aspirin, or the consequence of diseases that affect this tissue, such as inflammatory bowel disease (Crohn’s disease and ulcerative colitis) and celiac disease (sensitivity to gluten). The latter diseases have been used as models of how impaired intestinal permeability initiates a chronic inflammatory process. To reduce silent inflammation, it is important to rule out food allergies (See the chapter “Food Allergy”), avoid drugs that damage the intestines, and maintain a healthy and intact intestinal lining. If you have inflammatory bowel disease, psoriasis, or celiac disease, consult the chapters that deal with these issues and follow the recommendations given.
The general supplementation guidelines given in the chapter “Supplementary Measures” collectively will ensure some anti-inflammatory effects. In particular, supplementation with EPA + DHA in the form of fish oils as well as with various flavonoid-rich extracts has shown anti-inflammatory effects, including an ability to lower CRP. Pine bark and grape seed extract appear very useful, as they exert a number of anti-inflammatory effects that in clinical trials have been shown to lower CRP.15,16 In a double-blind study in patients with osteoarthritis of the knee those who took 100 mg pine bark extract (Pycnogenol) per day saw their CRP levels decrease from baseline 3.9 mg/l to 1.1 mg/l, whereas the control group had no significant change. Other markers of inflammation also declined with pine bark extract.
Specific botanical medicines to reduce silent inflammation are usually not necessary, as the recommendations for diet are far more important. Nonetheless, there may be some specific situations where CRP is stubbornly resistant to falling. In these situations, curcumin, the yellow pigment of turmeric (Curcuma longa), may be helpful because of its variety of anti-inflammatory effects.17
One concern regarding curcumin has been absorption, but there now exist a number of methods and products that enhance the absorption of curcumin. One of those products, Meriva, complexes the curcumin with soy phospholipids. Absorption studies in animals indicate that peak plasma levels of curcumin after administration of Meriva were five times higher than those after administration of regular curcumin.18 Studies with another advanced form of curcumin, Theracurmin, show even greater absorption (27 times greater than regular curcumin).19 In a study in patients with osteoarthritis a dosage of 1,000 mg Meriva (providing 200 mg curcumin) for three months decreased the level of CRP from 168 to 11.3 mg/L.20
Turmeric can also be consumed liberally in the diet, but since curcumin is so poorly absorbed, Meriva at a dosage of 1,000–1,200 mg per day or Theracurmin at a dosage of 300 mg per day can be used.
WHAT IS THE DIFFERENCE BETWEEN AN HERB AND A SPICE?
Technically, an herb is a plant that does not have a woody stem. If a plant has a woody stem, it is referred to as a shrub, bush, or tree. The term herb is also used to describe a plant or plant part that is used for medicinal purposes. A spice, on the other hand, is technically a plant product that has aromatic properties and is used to season or flavor foods. Most spices are derived from bark (e.g., cinnamon), fruit (e.g., red and black pepper), seeds (e.g., nutmeg), or other parts of an herb, tree, or shrub, while herbs for cooking typically use the leaves and stem. This makes for an easy way of distinguishing an herb from a spice. But can herbs be spices and can spices be herbs? Yes, of course. Many herbs are used to flavor foods, thus meeting the definition of a spice, and most spices can be used for medicinal purposes, thus meeting the second definition of an herb. To reduce silent information, make liberal use of spices in particular—turmeric, ginger, cayenne pepper, cinnamon, and other spices all exert significant anti-inflammatory effects, ideal for reducing silent inflammation.
QUICK REVIEW
• Silent inflammation is a major factor in the development of virtually every major chronic degenerative disease, including cardiovascular disease, allergies, type 2 diabetes, cancer, and Alzheimer’s disease.
• The most common test to measure silent inflammation is blood determination of C-reactive protein (CRP).
• Abdominal obesity is the strongest predictor of silent inflammation and CRP levels.
• The higher the diet is in foods that raise blood sugar levels, the higher the CRP level will be.
• The Mediterranean diet and a diet rich in flavonoids (found in soy, apples, berries, and other fruits and vegetables) are also associated with lower CRP levels.
• The ratio of omega-3 to omega-6 fatty acids is a major factor in determining the degree of silent inflammation and CRP levels.
• Regular, moderate exercise reduces the level of silent inflammation.
• Pine bark and grape seed extract appear very useful, as they exert a number of anti-inflammatory effects that lower CRP.
• Curcumin may help lower CRP in cases not responsive to diet and general supplementation guidelines.
TREATMENT SUMMARY
Research has left little room for doubt that diet is a major factor in silent inflammation. Diet is the major contributor to the development of insulin resistance. Decreased sensitivity of body tissues to insulin results in elevations in blood sugar and increased oxidative stress. Insulin resistance is largely the result of abdominal obesity and excessive consumption of calories, particularly carbohydrates. In fact, abdominal obesity is the strongest independent predictor of silent inflammation and CRP levels.4,5 Therefore, the guidelines given in the chapter “Obesity and Weight Management” should be regarded as the first step in reducing silent inflammation in overweight or obese individuals. CRP levels generally correspond to insulin sensitivity. In other words, when insulin sensitivity is good, CRP levels are much lower than when insulin sensitivity is poor. Not surprisingly, diabetics’ CRP levels are generally high.
• Do not smoke.
• Achieve and maintain ideal body weight.
• Exercise on a regular basis.
Follow the dietary guidelines in the chapter “A Health-Promoting Diet.” Specifically, it is important to do the following:
• Follow a low-glycemic, Mediterranean-style diet and increase consumption of fiber-rich plant foods (fruits, vegetables, grains, and legumes).
• Consume less saturated fat and cholesterol by reducing or eliminating the amounts of animal products in the diet.
• Increase consumption of monounsaturated fats (e.g., nuts, seeds, and olive oil) and omega-3 fatty acids.
• A high-potency multivitamin and mineral formula according to the guidelines given in the chapter “Supplementary Measures.”
• Key individual nutrients:
Vitamin C: 250 to 500 mg one to three times per day
Vitamin D: 2,000 to 4,000 IU per day (ideally, measure blood levels and adjust dosage accordingly)
• Fish oil: minimum 1,000 mg EPA + DHA per day
• One of the following:
Grape seed extract (>95% procyanidolic oligomers): 100 to 300 mg per day
Pine bark extract (>95% procyanidolic oligomers): 100 to 300 mg per day
Some other flavonoid-rich extract with a similar flavonoid content, super greens formula, or another plant-based antioxidant that can provide an oxygen radical absorption capacity (ORAC) of 3,000 to 6,000 units or higher per day
If the high-sensitivity C-reactive protein test shows that CRP is not responding to the above recommendations after a three-month trial, add one of the following curcumin products:
• Meriva: 500 to 1,000 mg twice daily
• BCM95 Complex: 750 to 1,500 mg twice daily
• Theracurmin: 300 mg one to three times daily