Sulfite as a Disease Vector

Sulfites cause an amazing number of diverse symptoms. On this page, I try to demostrate how sulfites are involved in chemical pathways that affect diseases such as asthma, allergy, stroke, heart attack and even autism. In many ways, sulfite interfers with our chemistry, thereby causing or complicating disease. As such, I use the term "disease vector" to colorfully describe sulfite's role. Sulfites activate immune signals, interfere with neurotransmitters, disable enzymes and play havoc all through the body. They are the Brimstone Demons bringing pain and misery to mankind.

Chemistry EquipmentTo begin, we must define a term used extensively in medical research, the mole. No, this is not a Russian spy hiding within our government. Nor is it a cute little rodent. A mole is a chemical unit describing the weight of a large number of molecules. A chemical's molecular weight in grams equals one mole. For instance, the molecular weight of sulfur dioxide (SO2) is about 64. So, a mole of sulfur dioxide would weigh 64 grams. A smaller, more convenient unit is the micromole (umol), one millionth of a mole. So, a umol of SO2 weighs 64 ug. Researchers must define concentrations and one standard is micromoles per liter (umol/L) otherwise abreviated as uM and read as micromolar.

What is the micromolar concentration of sulfite in our blood due to poor food choices? If a food releases sulfur dioxide upon digestion, it enters our blood stream which typically contains about 5L (liters) of fluid. If you are like me, your body does not process the preservative efficiently and it hangs around for many hours, causing mischief all the while. At its worst, the concentration may be defined as the absorbed weight of the sulfur dioxide (SO2) component divided by 5L of blood. For instance, a supersized 22 ounce cola is contaminated with about 320 ug of SO2. So, if you drank that cola, your blood concentration of SO2 would peak at 1 uM. The table below gives some other examples.

Peak Blood Concentration of SO2 from Typical Food
 ( One Micromolar Equals 1uM=64ug/L=320ug/5L )

Food Serving Size SO2 Weight
Peak Concentration
Supersize Cola
22 ounces
320 ug
1.0 uM (micromolar)
Fastfood Pizza
4 slices
Typical Fastfood Lunch
1 lunch
Dried Apricots
1/4 cup 8,800
White Wine
2 glasses
Bad Day in America
3 ugly meals
Bactrim Sulfadrug
800 mg

A "Bad Day in America" would include 3 meals built from the worst of sulfited ingredients, like white grape juice, dried fruit, fastfood fries, instant potatoes, wine vingear, pickled peppers, molasses, sauerkraut, etc. And this doesn't include wine. Such a day would not occur very often but is a possiblity. Since I get headaches at 1 uM, the table above scares me to death. However, if you can drink a gallon of wine and suffer no hangover, you may ignore it.

Asthma and Allergy

CockroachI've always been intrigued by the heavy correlation between sulfites and asthma. According to most sources, sulfites are the trigger in 5-10% of cases. And according to studies like Doai Memorial Hospital in Japan, for asthmatics with other triggers, 65% are overly sensitive to sulfites which cause symptoms seemingly unrelated to asthma. How is it possible that sulfite sensitivity and asthma are shared by up to 75% of patients? I hate to belabor the obvious but sulfites must be fundamentally involved at the very root of this disease. Note that the increased use of sulfites tracks the growth of asthma over the last 50 years. And, fast foods loaded with sulfites have increased asthmatic symptoms in teenagers the world over. Asthma is triggered by a wide range of insults. Allergic triggers include pollen, mold spores, dust mites, cockroach and pet proteins. Non-allergic causes include smoke, odors, cold air and weather, NSAID medications, exercise, hormones and sulfites. In my opinion, sulfite is the common denominator, acting as both a trigger and an enabler.

Consider the following results of biochemical research over the past 20 years at sulfite concentrations as low as 10 uM.

(1) Martin Pelletier, "Activation of Human Epithelial Lung Cells by the Pollutant Sodium Sulfite", Toxicological Science, September of 2002.
(2) H. Mitsuhashi, "Sulfite Is Released by Human Neutrophils in Response to Stimulation with Lipopolysaccharide", Journal of Leukocyte Biology, November of 1998.
(3) Pierrette Labbe, "Functional Responses of Human Neutrophils to Sodium Sulfite in Vitro", Experimental Toxicology, July of 2016.

Sulfite invokes an inflamatory response from epithelial lung cells, causing the release of interleukin-8 which is a signal that attracts neutrophil cells.(1)  Neutrophils are the most common type of white blood cells, soldiers in the body's immune system. Neutrophils produce significant amounts of sulfite as a mediator of immune response.(2)  Sulfites and other chemicals are released to destroy invading germ cells and/or allergens. Neutrophils react to sulfite within 5 minutes by generating superoxide anions, another tool of the immune inflamatory response.(3)  In summary, exposure to sulfite begins a lung cascade that initiates inflamation, sounds an alarm, attracts white blood cells and primes the immune system for allergic damage by any number of asthma triggers. And this cascade applies to allergies as well as asthma.

Stroke and Heart Attack

Great progress has been made in conditions affecting cardio-vascular health. Even so, stroke and heart attack stubbornly remain the primary causes of death in the western world. A major player in heart chemistry is the neurotransmitter nitric oxide (NO). And guess what, nitric oxide is affected by sulfite. Consider:

(4) Stephan B. Harvey, "Reaction of Nitric Oxide and its Derivatives to Sulfites ...", Biochemica et Biophysica Acta, 1995.
(5) Vikas Kapil, "Dietary Nitrate Provides Sustained Blood Pressure Lowering in Hypertensive Patients", Hypertension, February of 2015.

Nitric oxide and carriers like S-nitrosoglutathione inhibit blood platelet aggregation and regulate smooth muscle tone. This is one of the primary mechanisms of blood pressure control. In experiments with human platelet concentrate, nitric oxide was able to block dangerous aggregation caused by the injection of bovine thrombin, a clotting agent.(4)  When sulfites were added, nitric oxide and S-nitrosoglutathione were suppressed and unable to stop the clotting. In other words, sulfite inhibited nitric oxide and caused a potential heart attack or stroke. The concentrations used in these experiments were chosen to meet the demands of measuring equipment and were higher than found in the human body. For instance, 4 uM of NO was required to prevent platelet aggregation. This in turn required 30 uM of sulfite to begin inhibition. According to Wikipedia, this much nitric oxide can lead to cell death. If you scale nitrix oxide down to under 1 uM, interference occurs at only 5 uM of sulfite and 30 uM would inhibit NO by 25%. From our food table, these concentrations are well within the range of ordinary living.

BeetsIf you are concerned about cardio-vascular health, my advice: avoid sulfites. What else can you do? Well, you could visit your local doctor for tests, blood pressure drugs and cholesterol lowering statins. You could also try adding nitrate rich foods to your diet. These include arugula lettuce, spinach and beets. Nitric oxide is normally produced in humans by an enzyme, nitric oxide synthase (NOS), acting on the amino acid L-arginine. However, there is a recently discovered alternate pathway via nitrate. Nitric oxide has the chemical formula NO which means a nitrogen atom bound to a single oxygen. It is an ionized gas and is dissoved in blood plasma within the body. Nitrate has the chemical formula NO3 with three oxygen. Nitrite is a cousin with the formula NO2 and two oxygen. To efficiently produce nitric oxide from nitrate, an enzyme called nitrate reductase is required. Unfortunately, humans lack this enzyme. But bacteria in your mouth produce lots of nitrate reductase. When you eat lettuce, spinach or beets, nitrate is absorbed in the intestine and released into your saliva. Friendly bacteria convert the nitrate into nitrite which is then reabsorbed and stored within the body. As needed, the nitrite can be reduced to nitric oxide. Peak concentrations occur between 3 to 6 hours after eating.

How well does nitrate work at lowering blood pressure? Double blind English studies show typical drops of 7 points for systolic pressure and 4 points for dyasystolic.(5)  To achieve this, 250 mL of beetroot juice was consumed daily. Being a natural guinea pig, I had to try it for myself. I bought an organic freeze dried product called "Beet, Beet, Beet" which is conveniently mixed with water. Now, how much to drink? Well, the English study used 250 mL which weighed about 250 grams. Looking at the label on a can of Safeway beets, this amount of beetroot contains 16 grams of carbohydrate. To get a similar amount of carbohydrate from the freeze dried powder, I used 2 scoops of 10 grams each. And sure enough, about 3 hours after drinking, I felt a slight pressure in my head as arteries relaxed and my pressure dropped about 10 points. Beet juice is also supposed to improve exercise performance, ED problems and varicose veins. If you want to try it, 300 grams (30 scoops) of "Beet, Beet, Beet" cost $30 on Amazon. You can also purchase a better known product, "Super Beets", for a little more money.

Autism Spectrum Disorder

Autism is one of the mysteries of our age. Everyone seems to have a different opinion about the root cause while its prevalence continues to grow, affecting 1 in 70 children by some estimates. Seventy years ago, autism was virtually unknown. It seems obvious that something has happened during this period to provoke a genetic suseptiblity that previously lay dormant. That's why some folks have suggested vaccines which have grown in number over this time period. Or, environmental toxins and food chemicals. Well, let me throw my hat into the ring and suggest the explosion of sulfites. Consider the following studies:

(6) P. B. Mills, "Urinary AASA Excretion is Elevated in Patients with Molybdenum Cofactor Deficiency", Journal of Inherited Metabolic Disease, March of 2012.
(7) J. B. Adams, "Abnormally High Plasma Levels of Vitamin B6 in Children with Autism Not Taking Supplements", Journal of Complementary Medicine, January of 2006.
(8) J. Yip, "Decreased GAD67 mRNA Levels in Cerebellar Purkinje Cells in Autism: Pathophysical Implications", Acta Neuropathol, 2007 .
(9) Xin Zhang, "A Mechanism of Sulfite Neurotoxicity: Direct Inhibition of Glutamate Dehydrogenase", Journal of Biological Chemistry, October of 2004.

Vitamin B6As discussed in the previous webpage, excess sulfite in the body acts on an enzyme called alpha-AASA dehydrogenase resulting in an increase of alpha-AASA and a cousin called P6C. In turn, P6C traps the bioactive form of vitamin B6 which leads to B6 deficiency. In cases of severe sulfite intolerance, there is a near total shutdown of B6, resulting in a form of epilepsy.(6)  The inhibition curve is rather steep, and by my interpolation, 25% of the enzyme is blocked at 33 uM.

A very high percentage (77%) of autistic children have plasma vitamin B6 levels higher by 2 standard deviations over non-autistic controls. This correlates with very low levels of the bioactive form of B6 called P5P or pyridoxal-5-phosphate. Apparently, the enzymes that convert ordinary B6 into its bioactive form function poorly in autistic children.(7)  No other factor is so universally represented in the autistic population. We know that B6 plays a part in many chemical pathways affecting every aspect of health. Severe deficiencies can even cause epilepsy. Sulfite significantly depresses this vitamin at concentrations of 33 uM. If most autistic children have marginal levels of bioactive B6, then the injestion of sulfites could make it dangerous. This might be harmful during a stressor such as an illness or vaccination.

What enzymes might be at risk if sulfites are present and P5P is dangerously low? One candidate is glutamate decarboxylase (GAD) which relies on P5P as a cofactor. Glutamate is a neurotransmitter that excites brain activity. GAD converts glutamate into gamma aminobutyric acid (GABA) which depresses brain activity. Together, they strike a balance to keep the brain calm but focused. Without bioactive B6, the balance is broken. There is emerging evidence that this is a problem for many autistic children.(8)  Another interesting enzyme is glutamate dehydrogenase. It is responsible for converting glutamate into alpha-ketoglutarate, a necessary component of the Krebs Energy Cycle. This pathway produces ATP, which is the main source of energy in cell biology.(9)  At just 5 uM levels of sulfite, ATP in rat brain and human liver cells start to feel the pinch. At 10 uM, the inhibition is 18% growing to 55% at 100 uM.  Depressed GABA signals and low ATP cell energy sounds like a very bad glutamate cocktail for chronic disease of all kinds, autism in particular.

These are just a few examples of the hundeds of enzymes affected by P5P and sulfite. What can be done? Reduce your sulfite load and supplement with P5P. A combination of vitamin B6 and magnesium was an early therapy suggested for autism. It was heavily promoted by Dr. Bernard Rimland who established the Autism Research Institute in San Deigo. He claimed strong results for large doses in the 400 mg range. More recent studies have shown only mild improvements in double blind trials. But note, all of these studies used the ordinary pyridoxine form of vitamin B6, not bioactive P5P. Since 77% of autistic children already have high levels of ordinary pyridoxine, giving more of it wouldn't help much. Just a few milligrams of P5P should prove more effective. Ask your pediatrician. Run a P5P blood test. And stay as far away from sulfites as you can manage. Please realize, I am not a doctor and this information is intended to enlighten but not to diagnose or prescribe.

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