Have you ever wondered why we call certain food as “junk food”? We usually understand that “junk food” has little or no nutritional value, right? Well, that is correct in a certain sense. However, there is another aspect to why “junk food” is junk, and this is related to what we have just covered in the last few posts about energy generation in cells.
One important process in energy generation is the maintenance of the proton gradient (see Jan 4 post). As mentioned: “This gradient drives the ions to move back to the matrix and as the ions pass through special channels that are associated with ATP synthase, ADP is phosphorylated to ATP.”
As you can see, the proton gradient is the one that drives the (hydrogen) ions to move back to the matrix and as they pass through special channels, energy (ATP) is created. If this gradient therefore is reduced or dissipated, then the driving force will no longer exist and no ATP is formed.
So what does this have to do with junk food? Well, here’s the connection. Some junk foods contain chemicals (usually the preservatives or coloring used) that reduce this proton gradient or driving force. How? These chemicals sequester or “smuggle” across the membrane the hydrogen ions without passing through the special channels with ATP synthase. Thus, no ATP is formed.
So, do you still wonder why “junk food” is junk?