We have all heard about LCHF, barefoot running, weight loss teas, colloidal silver, waist trainers... it’s a jungle out there! Something that has been written extensively about are sweeteners, where aspartame is the most mentioned one. Aspartame is a substance that most people associate with illness, which is not surprising considering everything you can hear on the news and read about in the newspapers. But is this true? Is aspartame really as dangerous as people seem to believe?

In order to discuss if aspartame is bad for you or not, one should know what the substance actually is. Aspartame (E951) along with sucrose, sucralose, cyclamate and acesulfame K is an approved synthetic sweetener. Per gram, aspartame contains 17 calories, but considering the amount needed to correspond to plain white sugar (sucrose), aspartame is basically calorie-free. Regarding the content, aspartame consist of two types of amino acids; phenylalanine and aspartic acid, which also can be found in our regular diet. These metabolise in the stomach and intestines to methanol. When JECFA (WHO's international expert group) in 1981 made an assessment using studies conducted on aspartame, they found that an intake of 40 mg / kg body weight and day (safe factor 100) is completely harmless. Several new evaluations have been made since then, but the recommendations remain the same. There are no findings that supports a reduced recommended daily intake, although aspartame is the most researched food additive (1)(2)

What people worry most about regarding aspartame seems to be its metabolite methanol. A common argument for this concern is that orange juice contains more methanol than drinks sweetened with aspartame, which actually is correct. Methanol can also be found in other fruits and juices in amounts that are completely harmless (2). However, there are a few studies that show that the methanol from aspartame is carcinogenic, but these studies have significant sources of errors. In particular, these studies have been conducted on animals who have been given doses of at least 4000 mg aspartame per kg body weight and day (compare that with the recommended daily intake of 40 mg / kg body weight and day). These studies are therefore not reliable and have been criticized by several other researchers and experts (3). Most studies also show that the methanol from aspartame doesn’t contribute to any health hazards.

Another common theory is that a drinks sweetened with aspartame would cause increased hunger and weight gain. This is something that is well studied and scientists gets the same results over and over; there is no association between aspartame and weight gain, hunger, blood sugar levels, insulin levels, cholesterol level or blood fat levels. (5)(6) A study from 2012 did a six-year experiment in which they compared water, milk, sugar-sweetened Coca Cola and Coca Cola Light regarding their impact on glucose tolerance, insulin sensitivity, blood pressure and levels of blood fat, blood sugar, insulin and leptin (factors that are being controlled when testing for diabetes eg.). The researchers could show a correlation between sugar-sweetened Coca Cola and liver fat, skeletal muscle fat, visceral fat (fat around organs), blood fat and total cholesterol while Coca Cola light had the same effect as water on all factors. (7)

But if aspartame is proven to be harmless, why are there still people who argue against it? If I can guess, I believe that many people think that aspartame is too good to be true. Calorie-free and harmless, is it even possible? People become dubious and do studies about it in hope to “prove the truth”. This is most likely the reason why the studies that come with these “revolutionary results” are so bad. The researchers are simply too eager to find significant results that they choose an inadequate method, to few participants and/or something else that makes the results doubtful. In conclusion, there are a few studies showing a correlation between aspartame and some negative health factors, but these correlations can only be found with very large amounts of aspartame. Like with everything in life it’s about balance, if you consume aspartame in a dose under the recommended daily intake (which most people do with a large margin) there really is no need for concern.

Emma Fredriksson, bachelor's degree in sport science and health, physical therapist student and bikini fitness athlete

Abrahamsson, L., Andersson, A. & Nilsson, G. (2013). Näringslära för högskolan. s. 52-53. Stockholm: Liber.

Livsmedelsverket (2016). Aspartam.     https://www.livsmedelsverket.se/livsmedel-och-innehall/tillsatser-e-nummer/sotningsmedel/aspartam/ [2017-05-21].

EFSA (2013). Scientific Opinion on the re-evaluation of aspartame (E 951) as a food additive. http://onlinelibrary.wiley.com/doi/10.2903/j.efsa.2013.3496/epdf [2017-05-25].

EFSA (2013). Statement on two reports published after the closing date of the public consultation of the draft Scientific Opinion on the re-evaluation of aspartame (E 951) as a food additive http://onlinelibrary.wiley.com/doi/10.2903/j.efsa.2013.3504/epdf [2017-05-25].

Anton, S.D., Martin, C.K., Han, H., Coulon, S., Celafu, W.T., Geiselman, P. & Williamson, D.A. (2010). Effects of stevia, aspartame, and sucrose on food intake, satiety, and postprandial glucose and insulin levels. Appetite, vol. 55(1), ss. 37-43.

Santos, N.C., De Araujo, L.M., De Luca Canto, G., Guerra, E.N.S., Coelho, M.S. &  Borin, M.F. (2017). Metabolic effects of aspartame in adulthood: a systematic review and meta-analysis of randomized clinical trials. Critical reviews in food science and nutrition, vol. 10.

Maersk, M., Belza, A., Stodkilde-Jorgensen, A., Ringgaard, S., Chabanova, E., Thomsen, H., Pedersen, S.B., Astrup, A. & Richelsen, B. (2012). Sucrose-sweetened beverages increase fat storage in liver, muscle, and visceral fat depot: a 6-mo randomized intervention study. The American journal of clinical nutrition, vol. 95(2), ss. 283-9.