Aspartame: Killing Us By Degrees -- Part II

By Pat ThomasThis article first appeared in the September 2005 issue ofThe Ecologist, Volume 35, No.7. This is Part II of theseries; this partexamines the chemical contents of aspartame.Aspartame Toxic ContentsAspartame is made up of three chemicals: the amino acidsaspartic acid and phenylalanine, and methanol. The chemical bondthat holds these constituents together is fairly weak. As a result, aspartame readily breaks down into its componentparts in a variety of circumstances: in liquids, duringprolonged storage, when exposed to heat in excess of 86°Fahrenheit (30° centigrade), and when ingested. Theseconstituents further break down into other toxic by-products,namely formaldehyde, formic acid and aspartylphenylalaninediketopiperazine (DKP).Manufacturers argue that theinstability of aspartame is irrelevant since its constituentsare all found naturally in food. This is only partially true andignores the fact that in food amino acids like aspartic acid andphenylalanine are bound to proteins, which means that duringdigestion and metabolism they are released slowly into the body. In aspartame, these amino acids are in an unbound or 'free' formthat releases greater amounts of these chemicals into the systemmuch more quickly. Similarly, the methanol present in naturalfoods like fruits, for example, is bound to pectin and also hasa co-factor, ethanol, to mediate some of its effects. No suchchemical 'back-stops' exist in aspartame.According toneuroscientist Russell Blaylock, the effect of aspartame'sbreakdown components on brain function is central to its knownadverse effects. Like monosodium glutamate (MSG) and L-cysteine, an amino acidfound in hydrolysed vegetable protein, aspartame is what isknown as an 'excitotoxin' -- a chemical transmitter that allowsbrain cells to communicate. Blaylock has written a book about them, "Excitotoxins: The TasteThat Kills," and says: "Even a minute over-concentration ofthese chemicals causes the brain cells to become so over-excitedthat they very quickly burn themselves out anddie."While aspartame manufacturers say aspartame cannotpenetrate the blood-brain barrier -- the tightly-walled membranethat keeps toxins from reaching the brain --Blaylock countersthat a number of factors make the blood-brain barrier moreporous, including exposure to pesticides, hypoglycaemia, allimmune diseases (such as lupus and diabetes), Alzheimer's andParkinson's, strokes (including silent strokes) and a wholerange of medical drugs. Under these conditions, ingesting aspartame-laced foods maycause a spike in the level of excitotoxins that directly reachthebrain, thus increasing the likelihood of adverse effects.Each of aspartame's main constituents is a known neurotoxincapable of producing a unique array of adverseeffects.PhenylalanineThe essential amino acid phenylalanine comprises 50 percent ofaspartame. In people with the genetic disorder phenylketonuria(PKU) the liver cannot metabolise phenylalanine, causing it tobuild up in the blood and tissues. Chronically high levels of phenylalanine and some of itsbreakdown products can cause significant neurological problems,which is why foods and beverages containing aspartame must carrya warning for PKU sufferers.But according to Dr. HJRoberts, sensitivity to aspartame is not limited to PKUsufferers. PKU carriers -- people who inherited the gene for thedisorder but do not themselves have the condition (around 2percent of the general population) -- are also more prone toadverse effects. In Roberts' data there is also a high incidenceof aspartame reactions among the close relatives of patients whocannot tolerate aspartame. Furthermore, there is evidence that ingesting aspartame,especially along with carbohydrates, can lead to excess levelsof phenylalanine in the brain even among those not affected byPKU.Athough phenylalanine is sometimes used as atreatment for depression, excessive amounts in the brain cancause levels of the mood regulator serotonin to decrease, makingdepression more serious or likely. Build-up of phenylalanine in the brain can also worsenschizophrenia or make individuals more susceptible to seizures.Moreover, a decrease in serotonin levels can result incarbohydrate craving. This could explain aspartame's lack ofeffectiveness as a diet aid.DKPDKP is a breakdown product of phenylalanine that forms whenaspartame-containing liquids are stored for prolonged periods.In animal experiments it has produced brain tumors, uterinepolyps and changes in blood cholesterol. Before the FDA approved aspartame, the amount of DKP in ourdiets was essentially zero. So no claim of DKP's safety can beaccepted as genuine until good-quality long-term studies havebeen performed. No such studies have been done.AsparticAcidAspartic acid (also known as aspartate) is a non-essential aminoacid that comprises 40 percent of aspartame. In the brain, itfunctions as a neurotransmitter -- facilitating the transfer ofinformation from one nerve cell (neuron) to another. Both human and animal experiments have demonstrated asignificant spike in blood-plasma levels of aspartate after theadministration of aspartame in liquids. Too much aspartate inthe brain produces free radicals, unstable molecules that damageand kill brain cells. Humans are five times more sensitive to the effects of asparticacid (as well as glutamic acid, found in MSG) than rodents, and20 times more sensitive than monkeys, because we concentratethese excitatory amino acids in our blood at much higher levelsand for a longer period of time. Aspartic acid has a cumulative harmful effect on the endocrineand reproductive systems. Several animal experiments have shownthat excitotoxins can penetrate the placental barrier and reachthe fetus. In addition, as levels of aspartic acid risein the body so do levels of the key neurotransmitternorepinephrine (also known as noradrenaline), a 'stress hormone'that affects parts of the human brain where attention andimpulsivity are controlled. Excessive norepinephrine isassociated with symptoms such as anxiety, agitation and mania.MethanolMethanol (wood alcohol) comprises 10 percent of aspartame. It isa deadly poison that is liberated from aspartame at temperaturesin excess of 86° Fahrenheit (30° centigrade) -- forinstance, during storage or inside the human body. The U.S. Environmental Protection Agency considers methanol a'cumulative poison due to the low rate of excretion once it isabsorbed,' meaning that even small amounts inaspartame-containing foods can build up over time in thebody.The most well known problems from methanolpoisoning are vision disorders, including misty or blurryvision, retinal damage and blindness. Other symptoms include headaches, tinnitus, dizziness, nausea,gastrointestinal disturbances, weakness, vertigo, chills, memorylapses, numbness and shooting pains in the extremitiesbehavioral disturbances and neuritis. The EPA tightlycontrols methanol exposure, allowing only very minute levels tobe present in foods or in environmental exposures. But Blaylocksays: 'The level allowed in NutraSweet is seven times the amountthat the EPA will allow anyone else to use.'FormaldehydeThe methanol absorbed from aspartame is converted toformaldehyde in the liver. Formaldehyde is a neurotoxin andknown carcinogen. It causes retinal damage and birth defects,interferes with DNA replication, and has been shown to causesquamous-cell carcinoma, a form of skin cancer, in animals.Several human studies have found that chronic, low-levelformaldehyde exposure has been linked with a variety ofsymptoms, including headaches, fatigue, chest tightness,dizziness, nausea, poor concentration andseizures.Formic acidFormic acid is a cumulative poison produced by the breakdown offormaldehyde. It concentrates in the brain, kidneys, spinalfluid and other organs, and is highly toxic to cells. Formicacid can lead to accumulation of excessive acid in the bodyfluids -- a condition known as acidosis. The small amounts offormic acid derived from the methanol absorbed from aspartamemay or may not be dangerous; there are no human or mammalianstudies to enlighten us.Part III of this series will discuss some of the problems withthe aspartame safety studies and approval process. Ecologist Online August 30, 2005 Dr. Mercola's Comment:Many health disasters, which arehighlighted by horrific personal accounts found on Web sitesagainst aspartame, can be attributed to its use. Just a few ofthe disasters that result from aspartame useinclude:Cancer Hair loss Depression DementiaBehavioral disturbances But that's not nearly all. Aspartame alone accounts foras muchas 80 percent of the adverse reactions to food additivesreported to the FDA. Many of these reactions are very serious,including seizures and death.A few of the 90 different documented symptoms listed in a 1994Department of Health and Human Services report as being causedby aspartame include: Headaches and migraines, dizziness, seizures, nausea, numbness,muscle spasms, weight gain, rashes, depression, fatigue,irritability, tachycardia, insomnia, vision problems, hearingloss, heart palpitations, breathing difficulties, anxietyattacks, slurred speech, loss of taste, tinnitus, vertigo,memory loss and joint pain. And, according to researchers and physicians studying theadverse effects of aspartame, the following chronic illnessescan be triggered or worsened by ingesting aspartame: Braintumors, multiple sclerosis, epilepsy, chronic fatigue syndrome,Parkinson's disease, alzheimer's, mental retardation, lymphoma,birth defects, fibromyalgia and diabetes.Is this really something you want to be eating?More than 5,000 products contain aspartame. It's in your bestinterests, as well as your family's, for you to read the labelsof any processed food you're concerned about.If you want the full story on aspartame, you'll want to considerviewing Sweet Misery, a 90-minute documentary that perfectlysummarizes its history.