In the previous article we have seen that Aspartame is present as a sugar substitute in almost every ready to eat processed food & diet foods. It is 200 times sweeter than the common sugar (Sucrose), that is why it is required in small quantity as compared to sugar to sweeten the food. Being very low in calorific value, it is considered as a healthy replacement for sugar in diet and weight loss food stuffs. It is either used as a sole ingredient to sweeten the food or it is used along with Sucrose & or High fructose corn syrup in processed foods. But is it really safe to consume? Are there any health issues associated with it?

There are a lot of adverse health effects that are documented to be associated with regular Aspartame intake. Let’s understand them one by one.

Once ingested Aspartame gets immediately metabolized into its three main constituents i.e. Phenylalanine, Aspartic acid and Methanol (Methyl Alcohol). These three Aspartame metabolites are responsible for all the health hazards that are linked with Aspartame.

  • NEUROLOGICAL PROBLEMS: All three metabolites of Aspartame as mentioned earlier are responsible for the majority of adverse neurological effects linked to Aspartame consumption.

  1. DUE TO PHENYLALANINE: Phenylalanine is itself an amino acid. Regular consumption of Aspartame through food causes increased levels of Phenylalanine within our body. It follows the same path used by other amino acids to enter the brain. Being present in a higher concentration than other amino acids it occupies the majority of places on the carrier which carries these amino acids from blood into the brain. Thus, levels of other amino acids in the brain that are necessary for the synthesis of important chemicals like dopamine, serotonin remains low. Dopamine and Serotonin are produced in a lesser quantity than required, which can result in a number of health issues such as. 

  •     Low Dopamine Level results in

                     – Parkinson’s Disease

  •     Low Serotonin Level results in

                     – Depression

                     – Anxiety

                     – Mood Changes

                     – Impairment of Memory

                     – Schizophrenia


  1. DUE TO ASPARTIC ACID: It is a second major metabolite of Aspartame. It gets converted into Glutamate inside the body. Under natural circumstances Glutamate functions as a neurotransmitter (substance responsible for transmission of impulses between neurons or nerve cells). Regular intake of aspartame results in accumulation of high levels of Aspartic acid and Glutamate in the blood and brain. Excess of Glutamate acts as a excitotoxin to the nerve cells. It excites the nerve cells to such an extent that the nerve cells start getting damaged or simply die. Damage to the nerve cells generate free radicals which in turn cause further damage or death of the nearby brain cells.

  •    a) Hyper excitation of nerve cells results in

                    – Epilepsy/seizures

                    – Shooting pain

                    – Joint pain

                    – Numbness/ spasms

                    – Headache and Migraine

  •   b) Nerve cell Damage and Death results in

                    – Parkinson’s Disease

                    – Alzheimer’s Disease

                    – Multiple sclerosis


  1. DUE TO METHANOL: It is the third metabolite of Aspartame. On continuous intake of Aspartame through food the levels of Methanol go on increasing within the blood. Although it is just 10% by weight of Aspartame. Human body lacks mechanism necessary to metabolize Methyl Alcohol (Methanol) effectively. It gets converted into Formaldehyde and Formic acid in the liver. It gets accumulated in the body over the period of time. Formaldehyde causes damage to the optic nerve (Nerve for the eye) and Retina (A layer inside the eyeball) causing Blindness. Damage to the nerve cells produce free radicals which further worsens the damage. The adverse effects due to Methanol are,
    • Blindness
    • Blurring of vision
    • Hearing problems.
    • Symptoms similar to multiple sclerosis
    • Headache
    • Dizziness
    • Behavioral problems


  1. DIKETOPIPERAZINE: When food containing Aspartame is stored for a prolonged period, the Phenylalanine (from Aspartame) gets partially converted to Diketopiperazine. Diketopiperazine has a Carcinogenic (cancer causing) effect on brain. It is responsible for the Brain tumors/Cancers.


  1. HYPERTENSION: The major metabolite of Aspartame i.e. Phenylalanine gets further metabolized (broken down) into Dopamine, Noradrenaline and Adrenaline inside human body. These chemicals have their effect on blood vessels. The blood vessels get contracted (narrowed down). This makes blood to flow through them with increased resistance. Which increases the pressure exerted by blood on the wall of these vessels. It leads to the development of hypertension.
  2. IRREGULAR HEART RHYTHM: Methanol (Methyl Alcohol) a metabolite of Aspartame gets converted into Formaldehyde. Human body cannot effectively metabolize Methanol and Formaldehyde. It gets accumulated within the body. It damages the cells and cause cell death. The free radicals generated in this process adds further to this damage. Damage to the cells and tissues of the heart results in its poor functioning, i.e. decrease in capacity of the heart (Cardiac muscles) to pump blood effectively can lead to the Heart failure in severe cases. Reduced efficiency of conduction system, leads to the irregular heart beat and rhythm and in severe cases sudden cardiac death.
  3. CHEST PAIN & HEART ATTACK: Methanol (Methyl Alcohol) damages the inner layer (Endothelium) of blood vessels. Damage/Injury acts a good source for the generation of Atherosclerotic Plaques inside the lumen of these blood vessels. Plaques narrow down the blood vessel lumen and obstruct the blood flow to the cardiac muscles. If the obstruction is mild it can cause chest pain (Angina) and if severe,it can lead to a heart attack (Myocardial Infarction).



Excess consumption of food containing Aspartame can lead to the development of Diabetes in an individual or worsen the blood sugar control in an already diabetic patient. Irony is that the maximum use and recommendation of Aspartame is among diabetic people. Now let’s see it,

  1. Excess intake of Aspartame increases the Phenylalanine concentration within the body. Excess Phenylalanine increases the secretion of insulin from pancreas. Increased secretion of insulin for a longer time can deplete the insulin stores & can also weakens the action of insulin. This culminates into Insulin resistance. Insulin resistance results in ineffective utilization of blood sugar, and the development of Diabetes Mellitus in a previously normal person.
  2. Aspartame alters the pattern of gut microorganismsIt increases the number of harmful gut bacteria (Firmicutes) and decreases the number of helpful one (Bacteroidetes). These harmful gut microorganisms increase the levels of Propionate (A fatty acid) in the blood. Excess of Propionate increases the absorption of sugar from the intestines into the blood. In such condition, if insulin resistance is also present can terminate in the development of Type-II Diabetes Mellitus.

  • HYPOGLYCEMIA: Whenever a person eats a food sweetened with Aspartame, the intense sweetness stimulates the taste buds of the tongue. This sends signals to the brain that sugar is coming in the body. It increases the release of insulin from the pancreas. Aspartame being a non-carbohydrate sweetener, body does not receive any sugar in reality. Insulin released as a consequence of signaling from the brain ends up metabolizing the existing sugar in the blood which may be already low. This further reduction in blood sugar results in hypoglycemia.

Human body has a protective mechanism by which it releases certain chemicals (e.g. Adrenaline) which maintain the balance of blood sugar and prevents blood sugar from getting excessively low by producing sugar from glycogen in the liver. Methyl Alcohol – one of the Aspartame metabolite interferes with the release of these protective chemicals and adds to the danger of hypoglycemia. This problem may be especially severe in Diabetic people on Anti-Diabetic treatment.