This is column number two about the first of Dr. Li’s five body defense mechanisms — the immune system — taken from his book “Eat to Beat Disease, The New Science of How Your Body Can Heal Itself.” The other four defense systems are angiogenesis, regeneration (stem cells), the gut microbiome and DNA repair.
Last week’s column discussed how the immune system helps fight off infections and cancer, and what we can do to enhance our immune system, especially during the current COVID-19 pandemic. Today’s column is about the dark side of the immune system — autoimmunity, when the system goes rogue.
Dr. Li puts it like this: “Autoimmunity is the term used to describe an overactive immune system, where normal cells and organs are attacked and their function is destroyed.” Examples are:
• Type 1 diabetes, which often starts in childhood, where the insulin-producing beta cells in the pancreas are attacked by the immune system.
• Multiple sclerosis (M.S.), where antibodies “attack the insulation called myelin, which coats your nerves,” resulting in damage to nerves, the brain and the spinal cord.
• Celiac disease, where an immune reaction to gluten in wheat, barley and rye damages the walls of the intestines.
• Lupus, where antibodies attack and cause inflammation of joints, skin, heart, kidneys and brain
• Rheumatoid arthritis, where autoantibodies attack joints.
• Scleroderma, where tissues and organs are attacked by the immune system, resulting in replacement by abnormal, hard, scar tissue.
• Hashimoto’s thyroiditis and Grave’s disease, where antibodies attack the thyroid gland.
• Inflammatory bowel disease (Crohn’s, ulcerative colitis) involve autoantibody-induced inflammation of the bowel.
• Psoriasis, where antibodies inflame the skin and joints.
Asthma and food allergies are conditions where the immune system overreacts to otherwise harmless allergens — pollen and food. According to Dr. Li, autoimmune conditions are becoming more prevalent in modernized societies, thought to be due at least in part to “dysbiosis of the gut microbiome, which… disrupts the normal control of the immune system.” Epidemiologic studies — where large populations are studied regarding what they eat, what diseases they get, and what they die from — such as the China Study show that in societies on a plant-based diet, autoimmune diseases are rare to non-existent.
To calm an overactive immune system, Dr. Li points to evidence you’re already aware of if you’ve been following these columns:
• A diet based on animal protein causes inflammation and also results in a disease-promoting (including autoimmune diseases) gut microbiome. Sugar and refined foods are also inflammatory.
• A plant-based, whole food diet low in sugar is anti-inflammatory, and supports a gut microbiome that will “produce its own anti-inflammatory metabolites like butyrate.”
In his book, Dr. Li cites several lab and human studies that support the aforementioned conclusions. Human studies are of course the most meaningful, and here’s an example of one: A group of MS patients were separated into two groups; one group continued its typical Western diet and the other group ate a vegan diet. After 12 months “participants who ate the high-vegetable/low protein diet had a threefold reduction in relapse of MS and reported less disability,” whereas those on the Western diet reported an increase in disability. After 12 months, the vegans had lower markers of inflammation, and also had a 35 percent higher level of gut bacteria called Lachnospiraceae, which produce anti-inflammatory short-chain fatty acids.
Medications are available to treat inflammation. Cortisone is one, but has multiple side effects with long-term use, including increased risk of infection. Newer medications such as Humira and Enbrel, used to treat rheumatoid arthritis also have side effects, including increased risk of severe and sometimes fatal infections, and increased risk of cancer.
Greg Feinsinger, M.D. is a retired family physician who has a nonprofit: Prevention and Treatment of Disease Through Nutrition. He gives a free presentation at 7 p.m. the first Monday of the month at the Third Street Center in Carbondale; is available by appointment for free consultations (379-5718).