The Bulletproof Diet: Lose Up to a Pound a Day, Reclaim Energy and Focus, Upgrade Your Life

by Dave Asprey

Artificial sweeteners are another common additive in processed foods, especially “sugar free” snack foods. Aspartame is one synthetic sweetener that is responsible for a large number of adverse reactions. I used to consume aspartame before I became aware of how harmful it is. I enjoyed its sweet taste and thought I was doing myself a favor by drinking diet soda (which contains aspartame) instead of regular soda. But I was wrong. Both MSG and aspartame caused my blood sugar levels to fluctuate so badly that it took years for me to sort them out. Because they don’t contain any real sugar or calories, it was hard to pin down aspartame and MSG as the causes of those blood sugar swings. Now that I’m aware, it’s amazing to realize what a stick of sugar-free gum with aspartame does to my performance! Aspartame, which is now marketed as AminoSweet as well as Nutra-Sweet, is made of two amino acids, which are protein’s building blocks. These amino acids wouldn’t be harmful if one of them, phenylalanine, wasn’t chemically altered. (Pardon the slight detour into biochemistry here.) The addition of a methyl ester bond to phenylalanine makes it taste sweet, but the side effect is that it makes it easy for phenylalanine to form free methanol (wood alcohol). There is methanol in vegetables and fruits, but when found there it’s bound to pectin and doesn’t harm you. When methanol is free, it gets converted into formaldehyde in the liver.8 This is just as poisonous to your body as it sounds...