While there have been multiple reports of users experiencing sudden and severe onset of migraine headaches after using of aspartame, studies done by various institutions would seem to indicate the link is not causal. The FDA says they have received the results of over 100 clinical trials and doxological studies, and upon review they have concluded that aspartame is safe for ingestion by the human population.

The search for a new type of artificial sweetener came in the late 1970s, after concerns were raised about the safety of saccharin, the original artificial sugar marketed under the name Sweet 'n Low. Saccharin was placed on the anticipated carcinogens list and remains on that list as it is known to cause cancer in animals; despite this it remains a highly popular sweetener.

Aspartame, marketed under such brand names as Equal and NutraSweet, was approved by the FDA in 1981, and is present in many diet drinks, foods and gum as well as being marketed heavily as a tabletop sweetener.

Aspartame is considered to be a helpful tool for those on diet programs, as it can be used to cut out sugars from the diet. It is an extremely low calorie food, and has been a boon to calorie counters across the globe.

In the past decade, many reports have been made by aspartame users concerning adverse effects, particularly in the case of migraine headaches. Patients claiming they suffered serious headaches after consuming aspartame took part in an in-depth study under the auspices of the Duke University Medical Center.

The study was conducted by Dr Susan Schiffman and funded in part by Monsanto/NutraSweet. NutraSweet, you will recall, is a brand name under which aspartame is marketed. Researchers evaluated 40 sufferers of aspartame related headaches.

Some subjects of the study were dosed with a 30mg/kg bw on days three and five of the double blind study. Others received a placebo. 35% of the subjects who took the aspartame developed headaches, while 45% of those on the placebo developed headaches.

There has been frequent criticism of the study due to its short term and below optimum conditions. Researchers counter by claiming that all the CDC guidelines had been complied with, so the results were valid.

These results of the study, which were published in the New England Journal of Medicine, claimed that no correlation whatsoever existed between consumption of aspartame and migraine headaches (1).

Allegations of aspartame promoting migraines are numerous on the world wide web. Over 200 studies have been done to determine the safety of aspartame and its relationship to everything from lymphoma to epilepsy. The FDA maintains it is perfectly safe (2).

The European Food Safety Administration published a review stating that aspartame had indeed caused lymphoma in laboratory rats, but since no other studies had shown similar results, concluded their study was faulty and declined to raise any concerns about aspartame (3).

The US National Cancer Institute evaluated nearly half a million 50 - 69 year old men and women and found no correlation between aspartame consumption and lymphoma, leukemia or brain tumors over a five year period (4).

The Scientific Committee on Food did an exhaustive review of more than 500 papers on the subject of aspartame and came to the conclusion that concerns about aspartame causing any adverse reaction were unfounded (5).

Proponents of the use of aspartame have raised concerns that the 'myth of aspartame headaches' can cause people to overlook severe medical problems and that blaming aspartame for migraines can endanger those with more serious health issues. It is goes without saying that you should consult your doctor about frequent headaches and migraine whether you think aspartame could be to blame or not.

Those with migraines who stop taking aspartame sweetened beverages and foods and experience a cessation of symptoms are said by the medical community to be experiencing a form of ingrained reaction - they believe strongly that the aspartame is the cause of their symptoms, so the absence of aspartame causes the pain to cease.

This is also expected to work the other way - that if they believe drinking an aspartame sweetened beverage will give them a headache, they will proceed to develop one - a theory upheld by the results of the placebo group in the Duke trial.

Nether premise has of course been proven conclusively, but so far no concrete medical evidence that aspartame causes migraines has been established either. Currently, the Duke study is widely considered to be the leading authority on the subject.

(1) New England Journal of Medicine Volume 317:1181-1185 November 5, 1987

(2) CFSAN/Office of Food Additive Safety April 20, 2007

(3) EFSA findings (Website available on request)

(4) Council on Scientific Affairs (1985) Aspartame. Review of safety issues.

(5) Scientific Committee findings Website available on request