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it spread around inside your mouth easier. Besides any cleaning effect, this has the by-product of making you feel like the toothpaste is doing something, which toothpaste manufacturers have found to be a great way to get people to buy more of their toothpaste.
    Mint is added to toothpaste for this same reason, as it leaves your mouth feeling cool, clean, and fresh, part icularly if it’s well distributed throughout your mouth. As Tracy Sinclair, one-time brand manager at Oral-B stated in the book The Power of Habit , “Consumers need some kind of signal that a product is working. We can make toothpaste taste like anything — blueberries, green tea — and as long as it has a cool tingle, people feel like their mouth is clean. The tingling doesn’t make the toothpaste work any better. It just convinces people it’s doing the job.”
    ( Interestingly enough, besides any real cleaning effect, sodium lauryl sulfate is added to shampoo for similar marketing reasons, as people perceive that foaming shampoo works better than non-foaming,  whether a particular brand’s foaming shampoo actually cleans better than some other non-foaming shampoo or not.)
    Back to your taste-buds -the sodium lauryl sulfate interacts with your sweet taste receptors, making them less sensitive, and thus dulling the sweet flavor. In addition to that, it also destroys phospholipids in your mouth, which are compounds that have the same type of effect sodium lauryl sulfate has on sweet taste buds, except the phospholipids dampen your bitter taste buds.
    T he net effect is that your sweet taste buds are dampened while your bitter taste buds become more sensitive. So when you drink something like orange juice, which normally has an overpowering sweet taste that masks an underlying bitter taste, it is going to taste drastically different -in this case extremely bitter.
    So if for some reason your morning routine includes brushing your teeth before eating, you can simply find toothpaste that is free of sodium lauryl sulfate, and sodium lauryl ether sulfate and the food you eat directly after shouldn’t taste awful, unless you’re bad at cooking, of course.
     
     
     
    BONUS FACT
     
    Sodium lauryl sulfate has been shown to act as a shark repellent. There is also evidence that it is effective as a microbicide when spread on your skin, particularly effective in helping to prevent infection from viruses like Herpes simplex and HIV, which are non-enveloped viruses.
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     

Why We Have a Seven-Day Week
     
    Two of the earliest known civilizations to use a seven-day week were the Babylonians and the Jews. The Babylonians marked time with lunar months, and it is thought by many scholars that this is why they chose a seven-day week (though direct evidence of lunar months being why they declared a seven-day week is scant).
    That being said, each lunar month was made up of several different cycles—on the first day, the first visible crescent appeared; on approximately the seventh day, the waxing half-Moon could be seen; on approximately the fourteenth, the full Moon; on approximately the twenty-first, the waning half-Moon; and on approximately the twenty-eighth, the last visible crescent. As you can see, each notable cycle is made up of about seven days, hence, the seven-day week.
    You’ll notice I used the word “approximate” a lot in there . This is because the Moon phases don’t line up perfectly with this schedule. As such, as far back as the sixth century BC (which incidentally is also around the time the Jews were captives in Babylon), the Babylonians would sometimes have three seven-day weeks, followed by an eight to nine day week, presumably to re-synchronize the start and end of the weeks to match the phases of the Moon.
    In their normal seve n-day week, the Babylonians held the seventh day of each week as holy, much like the Jews did and still do. However, the Babylonians