ed that out of a group of people on identical diets, those who desired chocolate had different microbial breakdown products in their urine than those who didn’t. In other words, there is strong evidence that people who crave chocolate have different gut bacteria! Another possible mechanism for the gut microbiota to regulate food cravings is through specific peptides, proteins that mimic human hunger or satiety hormones. By making you feel hungrier or less hungry, your gut microbiota can further control your diet. On an interesting side note, your body has actually developed antibodies against these peptides. Yet, the defect with your body’s antibodies is that they cannot flawlessly distinguish between the bacterial peptides and real human hormones. Therefore, even if your body’s antibodies successfully target all of the peptides that the bacteria produced, they will target your human hormones as well, which will affect your hunger or satiety hormones. You will therefore feel more or less hungry than your body actually intended, which means that bacteria successfully manipulated your diet! So, are you wondering if there are ways to regulate your own cravings rather than letting some bacteria in your gut run the show? Well, first of all, scientists have noted a fascinating correlation between the lack of diversity of gut bacteria and obesity. This would make sense in light of the current theories. A less diverse gut microbiota contains a smaller amount of species that have larger populations than a more diverse gut microbiota, which contains many different types of species that all have small populations. Researchers have proposed that since the large bacterial species in a less diverse gut are competing with fewer other bacterial species, they can devote more of their resources to manipulating the host’s diet and consequently cause obesity. Focusing on cultivating a diverse microbiota is a proposed solution to conquering gut bacteria’s control on food cravings. Additionally, professionals are hopeful that the use of probiotics (beneficial bacteria) and prebiotics (food for these beneficial bacteria) can help individuals positively alter their gut microbiota. Next time you have a food craving, just remember that it may not be you who wants that ice cream sundae. Rather, it’s some of the trillions of microbes sitting in your gut.
Are Diet Sodas Making You Fat? Eva Ingber
Many SAR students love diet sodas, including myself. During lunch and Mincha-break, I often see kids rush into The Kosher Market to buy a Diet Coke or Diet Snapple, sometimes even more than one! Ever since soda brands started selling diet versions of their products, people have been snatching them off the shelf as a substitute for the ones containing real sugar, claiming that “fake sugar must be healthier!” Well, I’m here to say, not necessarily. Recently, a team of Massachusetts General Hospital (MGH) investigators discovered that the popular sugar substitute aspartame (often found in diet sodas) is not beneficial to one’s health, and can actually be detrimental. Specifically regarding weight loss they discovered that, in contrast to popular belief, aspartame does not promote weight loss-- it prevents it! The head of the study Richard Hodin, MD, explains “that aspartame blocks a gut enzyme called intestinal alkaline phosphatase (IAP) that we previously showed can prevent obesity, diabetes and metabolic syndrome; so we think that aspartame might not work because, even as it is substituting for sugar, it blocks the beneficial aspects of IAP.” In order to support their hypothesis, Hodin and his team conducted various experiments on mice to clearly illustrate aspartame’s effects on weight. In one such experiment, two groups of mice were fed a normal diet, but of the two groups, one also received aspartame. In addition, they also fed two other groups of mice a high-fat diet, and again only fed one of those groups aspartame. Upon observing these mice for periods of time, they discovered little difference between the weights of the two groups fed a normal diet. However, there was a major difference between the weights of the mice fed high-fat diets; of the two groups, the mice fed aspartame were significantly heavier than those not given aspartame. In addition, the team also realized that the aspartame fed mice in all four groups had higher blood sugar than those not fed aspartame, indicating glucose intolerance, and that these mice also had more of the TNF-alpha protein in their bloodstream, indicating an inflammatory reaction associated with metabolic syndrome. Ultimately, MGH’s study clearly illustrated the negative effects of sugar substitutes and disproved the common misconception that foods containing fake sugar are in fact healthier than those containing the real thing. So, for those of us who think “no calories, no problem,” think again.
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