Tuesday, January 24, 2012

F@%&ing enzymes, how do they work?!

The new age crowd is always an excellent source of fodder for science-y bloggers who enjoy taking a critical look at their claims.  Everything from good vibrations (in a literal sense) to conspiracies about flouride in tap water seem to fall under the "new age" umbrella.  Today's post is brought to you by the folks over at Natural News regarding a "news" story by Charmaine D. Mercado called The Healing Power of Enzymes for Treating Disease.  It announces the importance of enzymes for all sorts of things, ranging from preventing heart disease and cancer to relieving allergies. Let's take a closer look, shall we?

My favourite part of almost all woo-based reporting is the constant referral to "many studies" without actually taking the time to cite them. Seriously, if you read an article that goes on and on about how there are lots of studies supporting their claim without specifying which ones, that's a good indication that the source isn't trustworthy. In this case, a "growing number of studies" are alleged to be demonstrating that enzymes (no, they're not going to tell you which ones) are great for treating diseases and improving health.

This is probably a good time to step back and have a quick refresher on what enzymes actually are. Enzymes, broadly speaking, are catalysts used by living organisms to increase the speed of the chemical reactions they're involved in. A lot of enzymes are made of protein(s) but some can be made of RNA (riboszymes) as well. Usually (but not always), enzymes are named after what they do and they end in "ase". For example, transferases transfer functional groups from one molecule to another.
So how do enzymes perform biological magic according to Mercado? It would seem that the first step is learning your enzymes. No, put that biochemistry textbook down! We can't trust textbook publishers! They're in bed with Big Pharma and whoever is responsible for putting rainbows in your sprinkler! The only one you can trust for the Truth™ is some stranger on an obscure new age natural cures site.

Remember when I said that enzymes speed up reactions? Not according to Mercado! Forget biochemistry class, enzymes also slow down or even stop reactions. In that case, I'm pretty sure they'll wash your car and balance your cheque book too (if you ask nicely). Consulting a biochemist (or anyone who is familiar with basic biochemistry for that matter) regarding enzymes will probably begin with a discussion on the 6 main classes of enzymes.

Of course, this article doesn't refer to anything based in reality so it only discusses three "types" of enzymes: digestive, metabolic and food. Yeah, I'm not entirely sure what makes all of those different either. It seems digestive enzymes are to be broken into four of their own classes: amylase, protease, lipase and cellulase. While these are all real enzyme groups, I'm not sure why they're grouped together like this. Proteases are not exclusively involved in breaking down protein for human digestion. I once learned about proteases first hand when I bought a fresh pineapple that I cut myself. Pineapples have a protease called bromelain which is present throughout the fruit with the highest concentration in the stem followed by the tissue near the rind. After eating quite a bit of the pineapple, I began to notice my mouth was feeling really raw and sore. This was a result of the bromelain breaking the peptide bonds that hold the proteins in my mouth together. Incidently, bromelain from pineapple juice is sometimes used as a meat tenderizer.

There's a less painful way of investigating enzyme activity at home. Human salivary amylases break down long chains of sugar (such as starch) into individual sugar molecules. If you take an unsalted cracker and leave in your mouth for a few minutes you should notice the taste change from somewhat salty to distinctively sweet.

That's more than enough real science for now, back to the article! Metabolic enzymes are the subject of the next paragraph. It appears metabolic enzymes are produced by the body, unlike digestive enzymes. The salivary amylase experiment I mentioned earlier will only work if the magic enzyme fairy secretly adds enzymes to your spit when you're not looking. I'm still not totally sure what "metabolic enzymes" are supposed to be but they seem to be involved in all sorts of delightfully ambiguous processes like "transportation of blood" and "detoxification of the cells". In case you haven't heard, haemoglobin is also a Big Pharma conspiracy I guess.

Finally, we are told about "food enzymes". This is where it all starts to make sense. This article is essentially pushing raw food diets. The idea is that cooking food denatures enzymes that help aid digestion. By denaturing said enzymes, the body has to make more of its own which is supposed to be exhausting... or something. There is a giant leap from enzymes found in food to immune suppression because of energy wasted making replacement enzymes. 

Of course, none of this is even remotely true. Different enzymes have different optimal environments. The enzymes of an arctic fish will work best at low temperatures and will lose function at temperatures that we would still consider quite cool. Conversely, thermophilic bacteria have enzymes that work just fine at 72°C.  Temperature isn't the only way to denature (break-apart) an enzyme either. Another important factor is pH.  If the pH of the surrounding environment is not optimal, the enzyme can become denatured. The pH of stomach acid can be anywhere between 1.5 and 3.5. Last time I checked, the pH of broccoli cells was well above that range so its enzymes will either stop functioning or completely denature in a human stomach.

That's not the only problem with this picture though. If our foods contain the enzymes needed to digest them, why aren't they digesting themselves as we speak? Seriously. Why aren't apples sugary soups by the time they get to the super market or my house? I don't think most of these raw food vegans who make claims similar to those in this article have thought this through.  Either way, without this mysterious dietary enzyme deficiency, the rest of claims collapse.

There are so many other things wrong with this story I won't be able to through everything, but there's one last issue I think should be addressed. At one point, Mercado suggests that proteases could even be used as an effective cancer therapy since cancer cells are made of protein and proteases break proteins apart. Maybe the enzyme fairy is supposed to stop the proteases from destroying non-cancer cells too. The stupidity is quite mind boggling. I suspect our friend Charmaine has never eaten a poorly cut pineapple.  I shouldn't be too hard on Charmaine. After all, the things she's advocating don't seem to be her original ideas. Like so many other crazy ideas pushed by fringe groups, there seems to be a single source for the claims. Thanks to Cappi for bringing it to my attention!

1 comment:

  1. Very funny, I like your style.
    Please watch this short video regarding a Doctor's experience with 'Green Food'("becoming modern day hunter-gatherers")and how using her scientific knowledge as well as an enquiring stubborness, she managed to raise herself out of a wheelchair and out of the downward health spiral known as M.S..


    (TEDxIowaCity - Dr. Terry Wahls - Minding Your Mitochondria )

    I agree with you that there's a lot of rubbish talked about how the body works and loads of ill informed articles on the subject, however, when Physicians are given only 2 weeks study of nutrition (it may be none by now), I do think both the Food Industry and Big Pharma have a lot to answer for.
    I'm presently studying Medical Herbalism, having realised over the years the need to embrace Science as well as Traditional knowledge, and to thoroughly research the known activities of the body, but I don't hold Science to be the 'god' that some do.

    That said, I'm pleased to have bumped into your blog, and look forward to future cheeky but 'scientifically informed' posts.