BIOC 223

During our last few weeks in orgo II with Professor Carrico-Moniz, we studied carbohydrates. It was super cool to hear them taught in a somewhat different perspective than how we approached them in biochem this semester. I appreciated that I already knew the various configurations and conformations of the carbohydrates, but also that had the additional knowledge of how these structures affected their functions and behavior. Someone asked why the 1,6 glucose linkages in amylopectin were necessary if amylose already had 1,4 glucose linkages, and it was something that organic chemistry alone could not describe. After taking biochem, I was able to say that the additional 1,6 linkages in amylopectin are able to help store glucose in our cells more efficiently to be used for energy in our bodies. Thanks biochem!

Recently, we’ve talked about good cholesterol and bad cholesterol, and associated them with HDLs and LDLs, respectively. As a reminder, HDLs collect cholesterol from the arteries and transport them back to the liver to be degraded and reused, while LDLs distribute the cholesterol/fat from the liver to the rest of the body. However, why do we need LDLs if they’re associated with bad cholesterol? LDLs are really only bad when they largely outnumber the HDL level in the body, but besides that its very useful for us to transport fat around our bodies. Lately one of my friends was hospitalized for his lack of fine motor control and decreased ability to control his reflexes. The doctors eventually found that the axon sheathes covering the axons in his brain were either thinning or had developed thinner than they should have and therefore his neurons were firing inappropriately. They also found that he was eating a lot of butter and creamer while he was in the hospital. Interestingly, it turns out that the myelin sheathes covering our axons are directly affected by how much fat we intake. This is a reason that its good to eat fat! Especially during early development. We need myelination in our brains in order for our neurons to fire properly and so that we can function properly.

This is a fairly short post, but it’s just been on my mind: what makes a trans-fat bad? We talked about this in class, but I found the visualization helpful. From this image, we can see that trans fats (e.g., margarine) are more rigid and unnatural for humans with our flexible cells, while cis fats (e.g., butter) have that flowing, bent, and less compatible fatty tail. I’ve always heard that fats that melt or soften at room temperature are the healthiest of fats, wheres those that don’t, like solid vegetable oil (e.g., Crisco), are unnatural and unhealthy in larger doses. I think our discussion in class about flowing cells really helps us to understand why! Now, you too can be the cool guest at all your next parties talking about why trans fat is out, and butter is in!

If we aren’t already, new research suggests we definitely will be by 2050. For some biochemical reason (which is still eluding scientists), heightened levels of CO2 in the atmosphere is significantly reducing zinc, iron and protein content in wheat and rice — by as much as 10% in the next 35 years. Soybeans and peas also seem to have reduced zinc and iron content. Since zinc and iron shortages in particular are already taking tens of millions of lives each year, and the world currently depends on these plants for ~70% of our nutritional content, these global climate change effects may be the worst yet on record. Increasing our carbohydrate intake to compensate for the nutrient loss would just add to our problems by making us obese.

Scientists are looking into the mechanism of the nutritional degradation process, so far to no conclusion, but we have other alternatives:

As discussed in foodie Jo Robinson’s book, Eating on the Wild Side, our staple foods have already had innumerable nutrients bred out of them — in favor of efficient packaging and storage. Apparently, modern Americans eat 7.5 billion pounds of fries annually (~30 lbs./person/year). I’m not surprised, since the first meal I saw after starting this post included some (picture below)! But, historically, Native Americans ate healthier varieties of potato, including the apio (potato pea). As it turns out, the apio has 3x the amount of protein of modern potatoes, as well as genistein — that beloved, cancer risk-lowering nutrient found in soybeans. Apios also lower blood pressure, go figure! So what’s the catch? Apios can take 3 years to grow to the size of modern potatoes, and even then their irregular. So much for the nutritional benefit! We’ve thrown apios away with as many as 5,000 other varieties of wild potato. But as nutrients become more precious, perhaps we’ll learn a lesson or two from the slow foods movement. I, for one, hope to garden my own apios. Green thumbs up from me!

BBC article: http://www.bbc.co.uk/news/science-environment-27308720