Is obesity genetic? Some people would like you to think so!

Every once in a while a story comes out that is so ridiculous that I can't help but comment on it. One such story was published today that posted the results of a study stating that childhood obesity is determined more by genetics than by environment, diet, and exercise.

Get real.

If it is true that genetics determines childhood obesity, why is there a sudden childhood obesity crisis that has surfaced only in the last few decades?

It takes thousands of years of adaptation for genes to evolve. If what the scientists say is true, we should have seen a crisis in childhood obesity long before now.

Also, if what they say is true about all these genetic predispositions to chronic diseases, we humans are so genetically flawed that it is ten kinds of miracles that we have lasted more than a few generations. Or, maybe something has happened in the last fifty years to altar our genetic structure, and not for the better, making us more "genetically predisposed" to a host of chronic diseases and conditions from autism to cancer to diabetes to obesity.

I chose the figure of fifty years because it certainly seems that the general health of the people in the United States (not true in other parts of the world) has gone downhill since the 1950s.

When I was growing up in the '50s and '60s "childhood obesity" was so rare that none of us had ever heard of it. On my block alone, just on my side of the street, there were twenty-seven children including me. Not a single one was obese. Not one!

In all my years attending public schools, I don't recall any more than a half-dozen students who were overweight. None were obese! One girl was type-I diabetic, and even she was thin. All the years my son was in school and I volunteered in the classrooms, there were never any obese children in his classes or in our neighborhood.

Maybe I just lived in genetically-blessed areas? I don't think so!

Could it possibly be that the pollutants – both intentional (fluoride) and unintentional (pharmaceutical waste from prescription drugs flushed down the toilet) – in our water are changing our genes?

How about the heavy metals in our fish?

Hormones in the milk, maybe? (Many young girls are now beginning to develop breasts at the age of eight! Rather than determine the cause of this abnormality, the medical community has suggested calling it the "new normal.")

Maybe pesticides and herbicides are changing our DNA, not to mention the genetically engineered and mutated foods we ingest without our knowledge because they need not be labeled for our safety.

What about the pre-packaged foods that contain additives shown to contribute to neurological damage, OTC weight control drugs that force and flush your body a dozen ways it was never meant to be? How about foods that sabotage the message from your stomach to your head to stop eating? Could these be changing our genetic structure, too?

Maybe children eat so much because the food they are given has been grown in soil burned out and depleted of minerals. Maybe it's because their bodies crave nutrients, but that the non-organic foods being served contain only 20% to 50% of the nutrients found in their organic counterparts.

But no…they tell us that it is our own genetic flaws that cause our problems. Parents no longer need to feel guilty for their children's obesity, just keep serving up all that chemically-endowed food!

Parents, if you feed your children bleached-flour and sugary breakfast cereals, pre-packaged processed meats on white bread for lunch, and soda-pop with their dinner-in-a-box in the evening, then yes, you should feel guilty. If the kids were receiving wholesome foods containing the nutrients their bodies needed without the chemical additives and preservatives, they probably wouldn't be overweight.

As I said in the beginning of this article, if our genetic flaws are so severe as to predispose us to all these chronic conditions – that by the way were rare or unheard of 100 years ago – it is absolutely a miracle that we as a species have lasted as long as we have! And, for heaven's sake, please don't tell me it's caused by sunlight! Our ancestors lived for thousands of years spending most of their day in the sun, and half of them didn't get cancer!

I don't believe these so-called flaws are natural. If indeed genetics plays the role we are told it plays in so many chronic conditions, then we have been exposed to something, probably many things, in the last century that has altered out DNA. (Atomic bomb testing, anyone?)

Here is the story that started this tirade:

(Just as a PS to the complexity of the issue, here is an article on DNA and how a particular sequence can be repeated but with a completely different meaning. As the author says: "This is like discovering that your recipe for chicken pot pie also contained the recipe for laundry detergent if you drop every second letter, or that your favorite song is also the national anthem when played backwards." It's a fascinating post, and the source of the DNA graphic at the beginning of this article.)

Nature tops nurture in childhood obesity: study

Thu Feb 7, 2008 1:26 PM ET

LONDON (Reuters) - Diet and lifestyle play a far smaller role than genetic factors in determining whether a child becomes overweight, according to a British study of twins published on Thursday.

Researchers looking at more than 5,000 pairs of twins wrote in the American Journal of Clinical Nutrition that genes account for about three-quarters of the differences in a child's waistline and weight.

"Contrary to the widespread assumption that family environment is the key factor in determining weight gain, we found this was not the case," said Jane Wardle, director of Cancer Research UK's Health Behavior Centre, who led the study.

Previous studies have pointed to environmental factors as the main cause of obesity, a major problem worldwide that increases the risk later in life of type-2 diabetes, cancer and heart problems.

The World Health Organization classifies around 400 million people worldwide as obese, including 200 million children under the age of five.

The British team looked at pairs of identical twins who share all their genes and compared their measurements with those of non-identical twins who share only half their genes.

A statistical analysis found that the differences in the children's body mass index and waist circumference were 77 percent attributable to genes and 23 percent due to the environment in which the children were growing up.

BMI is calculated by dividing weight by the square of height.

"These results do not mean that a child with a high complement of 'susceptibility genes' will inevitably become overweight, but that their genetic endowment gives them a stronger predisposition," the researchers said.

The results suggest that parents whose children are at the greatest genetic risk may need support to make sure they provide a healthy environment, the researchers said.

"This study shows that it is wrong to place all the blame for a child's excessive weight gain on the parents," the researchers said.

(Reporting by Michael Kahn, Editing by Will Dunham and Tim Pearce)