Why are bananas bent?

Because it’s natural, written in their genes. The banana is negatively geotrophic, meaning they grow up against gravitational pull. Cool huh? You won’t see an apple or a cherry try that. You see, the banana starts out straight as the bunch emerges, and then becomes bent as it grows older, just like a radical teenager. The pull tab is where the banana was joined to the plant and the black nubbin at the end is what remains of the flower, at one time pointing upwards. Bananas: the anti-gravity fruit.

Getting kids to eat their veggies

Vegetables were probably never that big in the human diet. We evolved eating meat, seafood, nuts, seeds, fruits, tubers, fungi, berries and insects because that’s where the kilojoules are. When you need energy (kJs/Cals) each day to survive, why bother eating a leaf (lettuce), a flower (broccoli) or something else that is mainly water? Add the fact that 10,000 years ago you never met your grandparents and anyone reaching the age of 30 was seriously old. Back then you weren’t eating to avoid the diseases of aging, such as cancer. You were eating to survive.

So what’s the point you are making?
Simply that humans didn’t evolve as big veggie eaters, so it is no real surprise that we still aren’t big veggie eaters. Sure, we have undeniable evidence that vegetables provide nutrients and bio-active compounds and that eating them helps us control our appetite, reduce our risk of heart disease and some cancers. They are very useful attributes as good-living folk should expect to live, on average, until they are 80-85 years old, not the 30-35 year life span of yesteryear.

Children & vegetables
When I talk to parents, I explain that enjoying vegetables does not come natural with most kids (or adults). Many vegetables are bitter, astringent or just plain bland. All parents know that veggies can be disguised in meatloaf, pasta sauce, stews, soups and the like. Recently a journal article suggested there is another tip that we could employ to swing a child towards a particular vegetable.

Researchers at the University of California told students (average age 20 yrs) that after conducting a series of interviews with them, they now had a good profile on their food preference as a young child, determining whether they either really loved or really hated a particular food when it was first consumed. They were also asked to rate their enjoyment of each food today. Three weeks after the interviews, the students were asked back, where they were given their “personalised food preference profile”. Unknown to them, it included one false statement.

It’s just a little white lie
Those with the false statement that they had loved to eat a specific vegetable as a child, actually started to believe it. They felt much more positively about the vegetable and were more likely to order and eat it. The improved positive view of the vegetable continued for at least two weeks even though they had been told only once, falsely, that they loved the vegetable as a kid.

What does it all mean?
With less than 5% of children eating the designated amount of vegetables each day, it is important that parents remain continually positive around veggies and salad. Parents might also include the line “You just loved tomato/peas/pumpkin when you were a baby. Couldn’t get enough of it”. Saying that a few times (not just once) just might entice that child to include it in their menu, without coercion. It certainly won’t hurt.

Reference: Acta Psychologica 2008; 129: 190-197

Pee sniffers help science

After a feed of asparagus, does your pee smell funny, like boiled cabbage, vegetable soup, or even asparagus? Scientists have recruited pee sniffers to help them find the compounds responsible and the proportion of “detectors” versus “non-detectors”.

To make the asparagus plant less attractive to parasites it produces a compound called asparagusic acid. This same compound, when eaten, is metabolised to other sulphur-containing compounds that provide the characteristic bouquet of your pee after you eat asparagus. Although we all excrete the same compounds after eating asparagus, only around one in two people from a Caucasian background, and nine out of ten from a Chinese background can detect the odour.

Asparagusic acid and its metabolites are harmless. So is their aroma. To me anyway, being a non-detector.

Fat cells are called adipocytes

They are called lots of other things too. Usually nothing too complimentary. When a person gains weight, do they increase the size of their fat cells or increase the number of fat cells they have? Or both?

Once you reach adulthood, the evidence suggests that the number of fat cells is the same in both lean and overweight people, so when you gain weight as an adult you are just cramming more fat into every fat cell such that they enlarge.

Conversely, weight loss in adulthood reduces the size of the fat cells, but not the number. Even those that have undergone surgery to reduce stomach size (gastric stapling) retain the same number of fat cells despite considerable weight loss.

The number of fat cells is determined during childhood
Having fat cells has always been important for human existence. Fat cells became storage packs for reserve energy to help us get through any food shortages we may have encountered. Without fat cells we might be able to live only a day or two without food. With fat cells we have a much longer opportunity to obtain food.

If you cannot change the number of fat cells during the adult years, then any difference in fat cell number must happen during childhood and adolescence. Although there is speculation as to when during our youth we can increase fat cells, it seems that adolescence is a key time of accumulating additional fat cells. You can see why there has been concern about overweight children – three quarters of them become overweight adults. Developing an excess of fat cells during childhood may be one contributing aspect to chunky adults.

Today’s fat is different to 1999 fat
About 10% of your fat cells are renewed every year. Old ones die and are replaced by fresh ones. The average lifespan of a single fat cell is around 8.5 years. Their ability to fill with fat is enormous. Someone at 140 kg having the same number of fat cells as someone at 80 kg just shows you how “efficient” they are at doing their job.

What does it all mean?
The adult body has around 80 billion fat cells. They are there for life, being lost and replaced slowly. You can’t change the number of fat cells you have at your 18th birthday. You can, however, have a big say in their size. The paper did not answer the question whether liposuction permanently reduced fat cell number, although they stressed that there is a “tight regulation of adipocyte number” through life.

Reference: Nature 2008; 453: 783-787

Watch thou eating habites

William Phiston’s book “The Schoole of Good Manners” was published in 1609, in which he states:
"Some thrust so much into their mouthes at once, that their cheeks swell like bagpipes. Others open their Jawes so wide, that they smacke like Hogges: some blow at the nose. All which are beastly fashions. To drinke or speake when thy mouth is full, is not only slovenly, but dangerous."

Especially for the person opposite, I would add. It does show that, sometimes, it is only the spelling of the advice that changes in 400 years.

William was also keen that you didn’t have your elbows on the table:
"Take heede that thou trouble none of them (table guests) that sit next thee with thine Elbowes, nor those on the other side the table with thy feete."

Or just get a bigger table William. I wonder what table manners have changed over time? A new one this century for our family has been: Hey, no texting at the table!

Food Addiction

Are you addicted to food? It is a question many have tried to answer. If you like sweet foods, chocolate, or pizza, does it follow that these foods have an unhealthy allure? There is a good chance that you crave food three times a day because you need food to survive. It’s called hunger. How does that differ to a desire to eat six Krispy Kreme donuts? (Here, I’ve made a wild assumption that Krispy Kreme donuts can be legally classified as a food).

Nutrient lack?
A favourite theory is that we crave foods that provide a nutrient that we lack. There is no science to back that view. Giving people a nutritionally complete milkshake for five days straight, and nothing more, still stimulated cravings for specific foods. Why wouldn’t it? Only milkshakes all day is boring. We are designed to enjoy a range of foods for pleasure, not just nutrients.

Chocolate is probably the most craved food in Western society. The common view is that chocolate, and cocoa specifically, has addictive compounds. Again there is no evidence for this. You will often read that we crave chocolate for its phenylethylamine (PEA). Two problems here. If PEA was addictive, then why don’t we crave cheese and sausages as they have greater amounts? Secondly, there’s very little PEA in chocolate, and the small amount present is rapidly broken down in the liver. Forget the PEA argument.

Opioids
There is a lot of evidence that the consumption of pleasant foods, whether that is chocolate, lobster or a double cream brie, triggers the release of natural endorphins (opioid transmitters) in the brain. That means if the endorphins weren’t released at the time of eating, we wouldn’t enjoy the food as much. And that is exactly what happens. Taking a drug called Naltrexone blocks the release of endorphins and dampens the enjoyment of the food, yet doesn’t affect hunger. In fact, Naltrexone doesn’t cause weight loss, suggesting that a craving for food is not the main cause of overweight.

There is also evidence that the environment can elicit a need for certain foods. If life isn’t working out as it should, it makes sense to your body that you eat foods, or drinks, that are comforting and increase the brain opioid levels. Tough day? A gin and tonic with some chocolate will take away some of the pain.

What does it all mean?
Dr Marcia Pelchat from the Monell Chemical Sense Centre in Pennsylvania says it is difficult to find a direct similarity between food craving and drug addiction. A liking for food is healthy and had an evolutionary benefit in encouraging us to seek food we enjoyed. An addiction to drugs may affect similar pleasurable brain transmitters in an unhealthy way. A case of pleasure going haywire. She says that, however, some overweight people often do exhibit “addictive” behaviour regarding food and this is exacerbated when they go through cycles of restriction and abundance (as in going on and off diets) as that can produce an addictive pattern of eating.

Reference: Journal of Nutrition 2009; 139: 620-622

Truly successful weight loss

No matter your age, you have constantly had to endure weight loss diets, books, magazines and television programs with their own version of the “weight loss breakthrough”. The first published diet book was unleashed in 1864 (that’s 145 years ago, just in case you thought it was a typo) by a gentleman called William Banting, an English coffin maker. It was called a “Letter on Corpulence”. It was also the first best-seller diet book.

13kg lost and kept off
Despite the constant message that virtually everyone fails to lose weight once they become a bit chunky, there is a significant group of people who have lost lots of weight (average 13kg) and kept it off for over a year (and many for over five years). Here is how they did it.

Key characteristics of permanent weight loss
Constant vigilance
Successful people weighed themselves regularly to ensure they remained on-track for a healthy weight. Once their weight began to rise they would quickly make adjustments to their eating and exercise to reverse the trend. They soon learned what had a positive impact on their weight and what didn’t.

Be active each day
The most successful weight losers were also the most active. Although 30 minutes of activity each day, such as walking, helped weight loss, the most successful people were active for 60 minutes a day. This activity can be spread over the day, such as a 30 minute bike ride in the morning and 30 minutes walking the dog in the afternoon. Imagine telling people they need to be active 60 minutes a day to stay lean. You can see why TV-advertised, “Look like this 19 year old model after 5 minutes-a-day” exercise machinery seems attractive.

Eat a low fat meals & snacks
Those that were able to keep their fat intake down found it the easiest eating style to lose weight and maintain a good body weight. Of course, eating plenty of fruit and vegetables, wholegrain breads and cereals, lean meats and low fat dairy foods all help keep the fat level low. Successful people still had the very occasional treat, take-away or restaurant meal, but the majority of their meals and snacks were low in fat and kilojoules.

Eat breakfast
Virtually all successful weight losers had breakfast every morning. Enjoying the first meal of the day helps people control their eating during the rest of the day.

Eating consistently
Most successful people eat a similar style of eating each day, whether it is a weekday, a weekend, or a holiday. There was no problem going out to dinner or having a gourmet breakfast occasionally because the moment successful people had a bit of an eating splurge they adjusted their subsequent meals or activity to compensate. For example, they added an extra 30 minutes to their morning walk when they had been out to dinner the night before.

Maintain the healthy eating and active lifestyle
Once successful people had maintained a weight loss for two years or more, they found it much easier to continue their lifestyle. In other words, once a healthy lifestyle became a habit, excess kilos stayed off permanently.


What does it all mean?
For an overweight person to successfully lose weight takes a lot of bloody hard work – much too hard for all but the most determined. Hard work is what it takes to endure, manage and succeed in many aspects of life: marriage, child-raising, career, and following the Fremantle Dockers football team. Life was always meant to be a challenge.

Reference: American Journal of Clinical Nutrition 2005; 82: 222S-225S; Obesity 2007; 15: 2470-2477