‘Pie hole’, colloquial for one’s mouth, is believed to have evolved in the USA in the 1980s from the British expression ‘cake hole’ (coined in the mid 20th century). Pie hole refers to a mouth, as in: Shut your pie hole or, in this case: Put less in your pie hole.

Wednesday, February 18, 2015

Flip-Flopping on Water Fluoridation

Something not many of us think about anymore is fluoride as an additive in water. Is it mind control? Or something more sinister? New research and reviews show that water fluoridation may not be just a playground for conspiracy theorists. Evidence shows fluoridating water doesn't improve dental issues and actually causes several health problems... Something worthy to sink our teeth into.

A few students in my class this semester brought up their concerns about water fluoridation (WF). Given there have been no big exposé articles in the media and no notable research articles from my dietitian news alert, I dismissed it... Until the nagging voice in my head lead me to investigate it myself. What I found surprised me...

Before we get to the root of the problem, a little about fluoride: It is widely distributed in the environment, occurring in the air, soils, rocks, and water. It is found in tea and some grains (therefore many cereal products) and foods/beverages processed with water that is fluoridated.
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In 1945 water supplies were first fluoridated for the medicinal purpose of preventing dental caries (commonly known as cavities or decay) in a Michigan city. WF was widely introduced at 1 ppm during the 1950s. This was when evidence* showed a reduction in dental caries with WF.

*Many scientists would like to note this widespread introduction was based on research that was later highly criticised for methodological flaws and selection bias.

Newer research shows no difference in dental caries between children drinking fluoridated vs non-fluoridated water. Many other countries followed the US and introduced WF, but in recent years have dropped the scheme due to concerns about safety and effectiveness.

Fluorosis occurs with the overconsumption of fluoride and ranges in severity from minor tooth discolouration to severe discolouration (more info here). In areas where WF exists, the incidence of fluorosis has increased. One of the many problems with WF is that the dose is widely variable depending on how much water is consumed.

The effectiveness of WF is controversial. Here's some background and evidence I drilled out earlier:
  • Tooth hydroxyapatite (the rigid matrix structure of bone and teeth) consists of calcium, magnesium, and phosphate. It is susceptible to decay induced by acid-producing bacteria. Fluoride interacts with hydroxyapatite to form fluoroapatite, which is less susceptible to erosion by acid-producing oral bacteria
  • However, much research shows fluoride is effective at preventing dental decay only by topical application eg: toothpaste, not drinking fluoridated water
  • Research shows the amount of fluoride found in water is unable to influence teeth caries, with the fluoride concentration in toothpaste being over 75,000 times greater than in water (and toothpaste is generally not swallowed/consumed)
Further, the remineralisation process is not dependent on fluoride. In fact, the calcium and magnesium content of tooth enamel are more important to fluoride's anticaries effect. This is concerning for individuals who are undernourished - in America about 1% of children are malnourished.

Excessive and prolonged fluoride consumption has been shown to increase development of certain cancers, hypothyroidism, negatively affect IQ in children and increase incidence/severity of dental fluorosis.

Dental caries are caused by physical, biological, environmental, behavioural, and lifestyle-related factors including:
- Bacteria
- Inadequate saliva
- High intake of carbohydrates and sugars
- Low access to dental services
- Poor oral hygiene 
- Malnutrition (particularly calcium and magnesium) and poverty

  • There is substantial evidence showing the minor benefits of WF do not outweigh the negative effects
  • Given the questionable evidence supporting WF for the prevention of dental caries, the policies surrounding WF require radical review and rethinking
  • Implementing targeted oral health interventions combined with community-wide awareness and education are more favourable fixes to fill the fluoridation fallout

Wednesday, February 4, 2015

Pt II Mexican Food at its Roots: Oaxaca

In order to truly do Oaxaca justice, a second article was warranted. Pt I was a holistic view of Mexico and Oaxacan history and the many foods originating from Mexico (and no it's not all tamales, tortillas and tacos, we're talking avocado, corn, tomato, chocolate, vanilla, etc.) Herein are the things I couldn't fit into pt I: food preparation and some specific pre-Hispanic/Oaxaqueño dishes and ingredients.

A journey to a food Mecca, like Oaxaca, isn't worth the trip if you cannot learn something of how to create the flavours back home... Yep, the dietitian took a cooking class. The standout dishes were sopa de flor de calabaza (squash blossom soup) and mole mancha mantele (literally translating to 'tablecloth stainer' because of its bright red colour and apparent tenancy to stain tablecloths.)
Our wonderful teacher and her beautiful outdoor kitchen. Also, I admire my husband's willingness to share this picture. 
Squash blossoms* are readily available in winter, and I'm talking by the bag-full. They're bright and beautiful, and taste somewhat meaty but still delicate. Nutritionally, they're low in calories (surprise surprise) and high in vitamins A and C. They're considered a delicacy and often feature in cheese dishes like enchiladas - which by the way, in Oaxaca aren't smothered in sauce like in the US, they're more like a large, crunchy quesadilla (ke-sa-di-ya).
Roasting the poblanos
The soup included onion, mushroom, corn kernels and poblanos (a type of pepper) with a chicken broth base. The poblanos were cooked over a gas stove burner until the skin was black, then put in plastic for 5 minutes to steam and par-cook. Then we skinned, seeded, sliced and added them to the soup. The blossoms are added in the last 5 minutes to preserve their delicate flavour and taste.
Prepping the soup
The mole mancha mantele is unique as it contains both a sweet and savoury aspect: pineapple, plantain, apple, allspice and clove, as well as ancho chillies (dried poblanos), onion, garlic and tomato. The fruits are chopped but left chunky in the sauce, while the savoury ingredients are roasted and blended before being strained to make the final sauce.
Blending the mole
The ancho preparation is the most interesting and probably the most crucial. Anchos have a distinct sweet and smokey smell. No real surprise, de-stemming and de-seeding are the first steps. They are then placed on a flat griddle pan on a gas stove for about 20 seconds per side (longer causes bitterness), then put into hot water for 5 minutes. After 5 minutes, the rehydrated pepers, along with some of their bathwater, join their friends (who were charred on the griddle pan) for a spin in the blender.
Final meal: Nopales pico de gallo salad, squash soup, mole mancha mantele
Because refrigeration was not traditionally available, whole chickens would be bought from the market and then boiled all day. A leg or thigh is pulled off and served in the mole (yes, everyone we asked preferred dark meat, it is more flavourful kind after all...)

The lack of refrigeration also lead to the drying and salting of beef, called tasajo. Tasajo often accompanies a tlayauda (t-lie-oo-da), or stuffed into one. A tlayuda, by the way, is a large crispy corn tortilla (like, the size of a large pizza) covered in a thin layer of beans (and lard) with shredded cabbage, a little cheese and often tasajo. It is then folded in half, like a giant quesadilla, and cooked on a kamal, served with various salsas (but no salad or vegetable.)
Top: two ladies cooking on a kamal. Left: Tasajo tlayuda. Right: cheese and squash blossom enchilada
Tasajo curing. Top right pic is a little smokey... due to the grilling of meat and lack of ventilation
I mentioned chapulines in pt I and wanted to explain, these are fried, limed, salted and spiced grasshoppers. By themselves they are very salty, but added to an omelet or enchilada... Thumbs up. One night at the market, we sat opposite a young couple from Mexico city who described chapulines as "the food of the future" after hearing a group of French tourists turn their nose up at the notion of insect eating.
Chaulines 3 ways: 1) with guacamole 2) mixed with cream cheese on a tortilla chip 3) in a cheese omelet
All the foods were a unique tasting experience. Many incorporated familiar ingredients but were prepared in ways very different to Australian or American cooking. Overall I found:
  • A lack of vegetables: the large tlayudas and enchiladas were served on their own (high in carbs with some meat and very little vegetable)
  • The moles are an interesting nutritional case: they do contain lots of vegetables which are then pulverised and strained. So it's like juicing or smoothie-ing, you're getting nutrients from the vegetables but missing the fiber and need to actually chew - both fiber and the act of chewing are associated with increased feelings of satiety
  • The corn cob on a stick (pictured in part I) is an excellent, falvourful vegetable snack. Why don't Americans have them at fairs? Americans love corn!
  • The markets were exploding with delicious fruit. We took full advantage and carried things like bananas and mandarins as snacks
*For any fellow gardener friends who grow zucchinis or other squash, they use the male blossom after removing the stamen and stem.
Top: Tlayudas. Bottom left: Tamale stuffed with mole negro & chicken. Bottom right: In a random kitchen/restaurant