[00:00] Have you seen that warning they put on diet sodas? Phenylketonurix contains phenylalanine. Why do they put phenylalanine in this? Well, that's what's weird. They don't. You do. Every single one of these sugar-free sodas from America carries a warning that it contains phenylalanine.
[00:14] And yet, none of them do. If you carefully sorted out all of their molecules, the number of phenylalanine molecules you would find would be zero. But in the United Kingdom, they use a different warning that hints at what's really going on. This is a diet coke I bought in London, and it says, contains a source of phenylalanine.
[00:30] Phenylalanine is an essential amino acid. Our bodies need it to live, but cannot synthesize it from scratch, so we have to get it through our diets. It's found in foods that contain protein, but one in about every 12,000 people are born with phenylketonuria,
[00:43] the inability to metabolize phenylalanine. When they consume it, they can't turn it into the neurotransmitters their brain needs, which can lead to altered brain development, seizures, disordered mood, memory, and focus, treatments include taking special supplements and following strict diets.
[00:58] It saves lives to warn people if your product contains phenylalanine. But this doesn So why does it say it does Well the answer is that it contains a different molecule aspartame Gram for gram aspartame contains the same number of calories as cane sugar or high fructose corn syrup but it about 200 times sweeter So while a regular
[01:18] soda needs to be sweetened with 39 grams of sugar or high fructose corn syrup, which is equivalent to about 36 gummy bears, a diet soda only needs to be sweetened with about two tenths of a gram of aspartame, making it essentially calorie-free. This is what
[01:33] a molecule of aspartame looks like. When you consume it, enzymes in your body cause it to go through hydrolysis, which means it involves water. Now during the chemical reaction, this bond right here breaks, and a water molecule donates
[01:45] its parts to create this molecule, aspartic acid. But also, this bond breaks and another water molecule donates some parts to create methanol, and this molecule right here. What is this one?
[01:57] Well, this is phenylalanine! So we've got a bit of a philosophical problem on our hands. America and Brazil require products that contain aspartame to say they contain phenylalanine. But I gotta say, I feel like Great Britain is being a bit more accurate here.
[02:13] These do not contain free molecules of phenylalanine. Instead, they contain marble blocks that microscopic sculptors in our bodies can chisel into phenylalanine, and it is neurotoxic to some.