Whenever I get asked the silly question if you could have anyone over for dinner dead or alive who would it be I can’t help thinking about Lao Tzu. A Chinese philosopher whose real name no one knows and who lived sometime between 300 and 600 BC. Lao-tzu advocated a life of simplicity, naturalness, and non-interference with the course of natural events in order to attain a harmonious life. If he actually did exist he was certainly an enlightened individual.
I came across this brilliant quote this week.
“Health is the greatest possession. Contentment is the greatest treasure. Confidence is the greatest friend.” -Lao Tzu
Why do some food and drink taste bad after brushing your teeth?
The main culprit here is a foaming and wetting agent found in most conventional toothpaste called Sodium Laureth Sulfate, also known as Sodium Lauryl Ether Sulfate (SLES), or Sodium Lauryl Sulfate (SLS). SLS has the ability to inhibit the receptors that detect sweet-tasting compounds.
Additionally SLS can break up the phospholipids of fatty substances on the tongue that keep bitter tastes from being too overpowering. When these phospholipids are broken down by the SLS, bitter tastes become enhanced. This is why when drinking orange juice after brushing your teeth you are likely only tasting the bitter citric acid or citrus bioflavonoids until the SLS can be fully removed from the oral cavity, either by ingesting it with saliva or rinsing with water.
SLS is an ingredient that would be best to avoid, especially putting in your mouth. (The bucal membrane is one of the most highly absorbable areas of the body). SLS is the esters of Sulphuric acid – also known as “Sulfuric acid monododecyl ester sodium salt”, the result of the ethoxylation process as previously discussed here.
Turns out that many of us were taught incorrectly about how our sense of taste work. (and possibly our visual and olfactory senses as well). Many of us in North America were taught about the ‘taste map’ of the tongue where certain areas were responsible for one of the four tastes – sweet, salty, sour, bitter. It is now understood that all of these taste sensations arise from all regions of the oral cavity that include the tongue, soft palate, and epithelium of the pharynx and epiglottis.
Each taste bud contains approximately 100 taste receptor cells that can detect compounds in each of the five basic tastes. The fifth being the now recognized taste sensation known as umami, a Japanese word to describe the taste sensation of amino acids or savoriness. The umami taste came about with the invention of MSG or glutamic acid (the dubious ingredient that makes non-fresh food taste good).
A recent study suggests that the taste bud may also have receptors able to differentiate the taste of fatty acids and maybe even metallic and water tastes. Taste like many of our senses is quite complex in that it engages our sense of smell and feel including thermal receptors. We don’t often think about this however we are also able to experience sensations of the previously mentioned fattiness and metallic nature and also dryness (tannins- astringent), prickliness or hotness (spicy peppers), coolness (peppermint – spearmint), numbness (again from hot peppers) and even recent science suggests a receptor for calcium.
Take a minute next time you are eating your favorite meal and reflect on the incredible sense that we call taste.
Nanoparticles in sunscreens.
The topic of nanoparticles in personal care continues to heat up. Firstly nanoparticles or nanomaterials are particles of extremely small size with the purpose to improve their intended applications. One nanometer (nm) is one-thousandth of a micrometer (m), one-millionth of a millimeter (mm) and one billionth of a meter (m). To put that size in perspective, 1 nanometer is roughly 100,000 times smaller than the width of a human hair.
One of the obvious concerns with regards to nanomaterials in personal care products is that their size allows them to penetrate the skin and enter into the bloodstream accessing organs and tissues. To compound this concern, there are virtually no studies that indicate the safety of these materials once they enter the body.
In the case of sunscreens, using physical reflective block UV filters like titanium dioxide and zinc oxide creates a white caking or heavy feel on the skin. With these ingredients now available as nanoparticles, the lotion can be a more smooth and silky feeling. Zinc Oxide is often referred to as a natural mineral present in the earth’s crust however, most zinc oxide used commercially is produced synthetically. The other misleading claim for nanoparticle zinc oxide and titanium dioxide was that they were more effective in their ability to block UV rays than their counterparts, a claim that has been proven not be true.
With relation to nanoparticles in sunscreens, it would appear the risks far outweighing the benefits. I believe that environmental and public interest groups are wise to demand government and industry complete testing and approval of nano-containing products before commercialization, not just for human health but also for their environmental impact.