Empowering Healthy Kids Blog

As we discussed earlier, evidence is growing that genetics is an important factor in childhood obesity. New longitudinal research from Canada shows now shows a link between income and obesity:

The study suggested that the impact of a neighbourhood’s poverty level rather than affluence may matter most in a child’s weight. It is possible that neighbourhoods may become more important as children age and have more freedom to access the neighbourhood. It is also possible that disparities emerge over time, as children are exposed to such environments over a longer period.

This got me thinking. Why would families on low-income be more likely to overweight and obese? Perhaps it’s simple economics: A family will try to maximise the amount of energy intake for the least cost possible - in other words more calories per dollar. If you spend a greater proportion of money on food, then you are sensitive to this equation. Apparently, I’m not alone with this opinion:

Healthy eating really does cost more.

That’s what University of Washington researchers found when they compared the prices of 370 foods sold at supermarkets in the Seattle area. Calorie for calorie, junk foods not only cost less than fruits and vegetables, but junk food prices also are less likely to rise as a result of inflation. The findings, reported in the current issue of the Journal of the American Dietetic Association, may help explain why the highest rates of obesity are seen among people in lower-income groups.

The scientists took an unusual approach, essentially comparing the price of a calorie in a junk food to one consumed in a healthier meal. Although fruits and vegetables are rich in nutrients, they also contain relatively few calories. Foods with high energy density, meaning they pack the most calories per gram, included candy, pastries, baked goods and snacks.

The survey found that higher-calorie, energy-dense foods are the better bargain for cash-strapped shoppers. Energy-dense munchies cost on average $1.76 per 1,000 calories, compared with $18.16 per 1,000 calories for low-energy but nutritious foods.

The survey also showed that low-calorie foods were more likely to increase in price, surging 19.5 percent over the two-year study period. High-calorie foods remained a relative bargain, dropping in price by 1.8 percent.

Although people don’t knowingly shop for calories per se, the data show that it’s easier for low-income people to sustain themselves on junk food rather than fruits and vegetables, says the study’s lead author Adam Drewnowski, director of the center for public health nutrition at the University of Washington. Based on his findings, a 2,000-calorie diet would cost just $3.52 a day if it consisted of junk food, compared with $36.32 a day for a diet of low-energy dense foods. However, most people eat a mix of foods. The average American spends about $7 a day on food, although low-income people spend about $4, says Dr. Drewnowski.

Researchers in the UK have found a strong link between childhood obesity and genetics:

more than three quarters of the difference between children’s waistlines, with lifestyle factors such as diet and exercise playing a much smaller role.

Lead author of the study, Dr. Jane Wardle:

Weight gain in a child is unlikely to be the fault of the parents and is more likely to be due to the child’s genetic susceptibility.

The study was conducted using a twin study and drew the following conclusions:

The researchers found that, overall, the twins’ heights and weights were greater than the 1990 averages, though BMI was similar. Waist circumferences were substantially higher than in populations in 1990, particularly in girls. They also found that identical twins were more likely than non-identical twins to have similar BMI and waist circumference measurements, suggesting a genetic component to these characteristics.

Using the modelling method, the researchers conclude that variation in BMI scores is 77 per cent heritable, while variation in waist circumference is 76 per cent heritable. They also found that the “shared-environment” had little effect on BMI and waist circumference (10 per cent each).

One problem that I find with these studies is that it shows correlation but not causation, but the researchers discuss such criticisms:

• Firstly, the common finding that the shared environment has little effect. In studies of obesity, this is surprising considering the fact that many models suggest that the environment is “the root cause of obesity”. They say that this finding suggests caution when assuming that if all parents followed “current child-feeding recommendations, the obesity problem would be solved”.
• Secondly, twin studies assume that identical and non-identical twins share the same environment (in the uterus and in the family). There is discussion in the scientific literature about whether this is an accurate assumption, however the researchers here say that the effect is small and “it would not materially change the conclusion”.
• Thirdly, such studies do not identify genes responsible for traits or behaviours. No major genes that cause obesity have been identified and obesity is likely to be due to the influences of many different genes, affecting appetite as well as how fat is stored. 

Until such time as the boffins find a “fat” gene can we understand the cause of obesity an, hopefully, from that finding the best ways to combat it. What this study also means is that parents who are overweight and obese must not abandon their and their children’s efforts to lead an active and healthy lifestyle. It just means they have to work a little harder at it.

I saw this once at Scienceworks - it looks like YMCA is using something similar to get kids moving:

The Y is using a unique, new product is called Neos. It’s designed to be set up outside on playgrounds.

“It’s an interactive game,” says YMCA childcare director Owenne Outlaw George. “It lights up a sequence of lights, and the kids run around and chase it to find which light they need to be hitting. It gets them moving, gets them active.”

Check the link for a (small) picture of the Neos in use.

I was fortunate enough to go back to my home town of Perth, Western Australia for the Australia Day long weekend. On a sunny afternoon, with the Fremantle Doctor providing some relief, my brother Ash organised a neighbourhood match. After the obligatory 1/2 hour of dilly dallying while picking teams, it was on. We won by about 50 runs - as is normally the case no one really kept track of the score at the end.

One thing that struck me were the fact that the boys (age ranging from 12 to 30*) was that they just couldn’t keep still. Players waiting to bat, practiced in the nets, others played soccer. I could do the usual thing and analyse how video games, TV (Aussies were playing India in the 4th test that day, by the way) hadn’t affected these kids. But it was just great fun.

By the way, I scored 1 run from 5 balls; dropped a catch that went for six; and went 0-6 of two overs. Urghh.

This is where we played:

Winthrop Primary

* I was the 30 year old

I recently contacted an old acquaintance, Erick Mueller, from my RMIT Uni days. Erick has launched a new venture in Colorado, US called Funovation Laser Maze Challenge (www.funovation.com). I asked Erick about his thoughts on how his venture can help kids get active:

Children desire to have fun and enjoy their lives. There are many avenues to this, but unfortunately a number of them involve sedentary options such as video games, TV watching and other “dulling” activities. The Laser Maze is a great alternative to this because:

a. It’s physically active. Children must bend, crawl, jump, hop, and contort their way around the laser beams to complete their “mission”. The more physically fit they are, the better they’ll perform and the more fun they’ll have.

b. It’s mentally challenging. It’s like a puzzle. Each child must determine his or her path and learn the best possible way to navigate through the web of lasers in the quickest time.

c. It’s fun! Children can pretend they are in the movies, portraying a jewel thief and having to navigate around the bank vault’s laser beam security system to capture the prized jewel. While at the same time being physically active. Not to mention, friends can challenge each other in scoring the lowest time and enjoy the lighthearted competition.

I believe children can have it all. They can have fun and enjoy their lives while also being physically active & fit. Games and activities such as the Laser Maze Challenge can be a part of this and offer a unique alternative to the sedentary options most kids today choose.

I’m inspired by your vision in ending childhood obesity and wish you the best as you make this vision a reality.

Thanks Erick and good luck with your venture!