 Today, we're going to be talking about specific health claims that we want you to investigate. Specifically, whether caffeine helps you study, should fluoride be added to my drinking water and can meditation reduce symptoms of depression? First of all, we want you to rate your first impression. We want you to make a commitment and then we want you to do some research, summarize the evidence and finally rate your final impression, whether you changed your mind about that particular topic. Think about what you're doing. You're trying to distinguish fact from fiction in an area that you probably have no expertise in. So you're going to have to read again, pass the headline, pass the first couple of quotes and get to the references. This is an expertise effect. I can't give you the tools to discriminate fact from fiction. You have to keep looking at it and keep getting feedback on your own decisions. That's what we do in our PhDs and I think we could do that better in our everyday lives as well. I've been drinking coffee for a whole lot of time and I don't know very much about it other than the structure of the molecules. Does the molecule help me study or does the symbol help me study? There was limited but some evidence that there was some improved memory recall, but only over 24 hour period. There was no available evidence about the side effects of water fluoridation that was actually peer reviewed. We don't know if this was a publication bias. Topically, yes, there's lots of evidence to say that that's fine if you just put it on your teeth and it works well, but actually when you look at it, putting it in the general water supply, the quality of the research isn't that good. In conclusion, we found that meditation may be able to help with certain symptoms of depression, but there's still further research needed. Mindfulness-based meditation can reduce state levels of depression and anxiety. However, it needs to be constantly practiced to maintain the reduced levels. Most of the studies said that, yeah, people that were doing meditation felt better, but that is easily explained by something like regression to the mean because we don't have a no treatment group to compare to. And if you're motivated to feel better, you've got to sell it again positively anyway, you've got to feel better. To really be able to say yes or no, we actually have to go look.