‘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.

Thursday, September 25, 2014

Prevent Brain Decay with Vitamin D

Low levels of vitamin D, often called the sunshine vitamin, was recently implicated in the development of Alzheimer's Disease and other forms of dementia. So here's an article about how a sunny day (and some diet adjustments) can help keep dementia away.

First off, in case you're asking 'who cares', here's why you should give two hoots about vitamin D:
  • It helps your gut absorb calcium
  • Calcium and vitamin D are your body's Batman and Robin superhero tag-team that keep your bones strong, healthy and osteoporosis-free
  • Vitamin D is involved in cell growth, reducing inflammation and has important immune functions (more on this shortly)
 
Your body makes vitamin D when your skin is exposed to sunlight. Factors like season, time of day, length of day, cloud cover, smog, skin melanin content, and sunscreen affect the body's ability to synthesise vitamin D.
Because vitamin D is fat soluble and stored in both the liver and fat tissue, the amount accumulated in sunny times is often enough to see us through the dark months...when the sun don't shine.

A new study looked at 1,5000 adults and found those who were moderately vitamin D deficient were 53% more likely to develop dementia. This risk increased to 125% in those who were severely deficient. I hear your internal struggle: Vitamin D... Dementia, I don't get it.

Vitamin D is well known for it's part in bone health, but most people don't know just how important it is in the immune system. Vitamin D is involved with clearing a class of proteins called beta-amyloid from the brain. When these are not eliminated, amyloid plaques form between neurons in the brain, and are a hallmark in people with dementia and Alzheimer's Disease.

Before you self-diagnose and stock up on a mega dose supplement of vitamin D, too much is problematic too, unless you like heart arrhythmias. Excess vitamin D also increases the calcium in your blood, which results in the calcification of blood vessels, the heart and kidneys... About as fun as walking into an electrocution chamber.

Instead, here are some foods that are good sources of vitamin D:
  • Cod liver oil (wait, it gets better)
  • Certain seafood like salmon, swordfish, tuna and sardines
  • Vitamin D-fortified foods like milk, OJ and yoghurt
  • Eggs (specifically the yolk)
It is difficult to give general recommendations for time spent in the sun due to variables like skin colour, time of year, cloud cover, air pollution, etc. It is also prudent to limit sun exposure, unless you're into skin cancers or looking like a leather bag.

In the end, the best offense is a good D (defense). Think: smart sun exposure and a side of vitamin D-rich foods.

Wednesday, September 10, 2014

Diets: Low Carb, Low Fat or Something Else?

"Which diet is best?" Such a depressing question, but one that is still being studied because people are still asking. It's big business too, with so many boutique and 'brand' name diets available.

A new study set out to strip down the evidence and see what was left underneath. This meta analysis analysed 48 randomised control trials (kind of the gold standard when we talk about study design) that included over 7,200 people. The median age was 45, median BMI was 33 (obese).

They divided the diets thus:
  • Moderate macronutrient (55-60% of calories from carbohydrates, 15% from protein)
  • Low carb (<40% of calories from carbs, 30% from protein)
  • Low fat (60% of calories from carbs, 10-15% from protein)
One note is that most government guidelines recommend ~45-65% of daily calories come from carbs (the US recommends >50% of that come from whole grains).

Just like my labrador, who swears by her monotonous duck and legume diet, people swear black and blue about their diverse, and often dubious diets.

The analysis found that low fat and low carb dieters had the greatest weight loss success at 6 months, about 8kgs. However, at 12 months, 1-2kgs of this effect was lost (aka, people gained it back).

If you're thinking lower carb, think glycemic index (GI). Good quality, whole grain carbs are a better choice than refined foods that are high GI. For example, oats are high in fiber and harder to digest than white bread... Make your intestines work for a living. Low GI foods aid weight loss and improve blood glucose/insulin regulation.

The study also found that exercise and education on behavioural changes enhanced weight loss. Kind of like how taking swimming lessons and staying in the shallow end of the pool decrease your chances of drowning.

Even though only minor differences were found between brand name diets (eg: Jenny Craig vs Atkins vs Southbeach vs Weight Watches vs Ornish vs Nutrisystem), we can take solace in that any diet/modification resulted in weight loss compared with no changes at all.

Many such 'organised diet programs' are expensive, have high attrition rates, and a high probability of regaining 50% or more of lost weight in 1 to 2 years. You're better off spending your money on fresh food rather than fancy, fad diets fraught with fleeting and frustrating results. After all, in my class, 50% is an F... Just saying.

Take home:
  • Behaviour changes form habits, rather than short term change
  • Making changes you can actually stick to in the long term will improve weight loss

An article from earlier this year about how different brand diets stack up.