The Great Debate Continues: Recent Findings About Genetic Causes of Obesity

When it comes to weight loss, one of the most heated controversies is a variation of the age-old ?nature or nurture? debate that scientists have long asked about many aspects of human health and behavior. In short, is obesity caused by our genetics, environment and upbringing, or by our family?s and ancestors? health, heritage, and medical history?

The question is so complex that it cannot be easily answered. Although scientists have been exploring this issue for decades, a definitive answer to the ?nature or nurture? question has remained elusive. Because the transmission and manifestation of genetic traits is such a complicated process that depends upon many variables, it may be that a simple ?yes? or ?no? answer to this question will never be possible.

Still, researchers continue to investigate the relationship between obesity and genetics, with significant new findings being announced on an ongoing basis. Here?s an overview of some of the most groundbreaking findings that have been released in recent months.

UK Researchers Uncover a Strong Genetic Link to Obesity

The results of a recent study conducted by UK researchers at the University of Oxford and the Peninsula Medical School in Exeter added fuel to the flames of the ?nature or nurture? controversy. According to the team?s findings, the presence of a certain gene was identified as increasing an individual?s risk of becoming obese by up to 70%.

The gene in question was referred to as the ?FTO? gene. Among a test group of over 40,000 subjects, it was found that individuals whose DNA had one copy of the FTO gene stood a 30% higher risk of developing obesity in adulthood. The individuals who had two copies of the FTO gene (i.e., one from each parent) bore a remarkable 70% greater risk of obesity than did their counterparts without the gene.

Relationship between Mother?s Age at Puberty and Childhood Obesity Probed

A research team based at the University of Cambridge recently released study findings that identified a possible connection between maternal menarche and the obesity risk of children, offering another perspective on the long-running debate over the role genetics play in determining weight.

Specifically, the researchers found that women who started menstruating earlier tended to have children who developed obesity during childhood and adolescence. Women whose first menstrual period began at or before age 11 typically gave birth to children who experienced rapid growth during their first two years of life, but then began to develop obesity and comparatively short stature in relation to their peers.

The researchers pointed out that girls born to women who began menstruation at an early age were also more likely to experience early menstruation themselves, which is another risk factor for obesity in adolescence and adulthood.

Study Identifies Genetic Differences in the Way Nutrients are Processed

A research team comprised of scientists from Tufts University and the US Department of Agriculture Human Nutrition Research Center found that different people process fat, protein, and carbohydrates differently, and that these differences can be partially ascribed to genetic traits.

Specifically, the researchers found that for a small number of people with a genetic variant of the APOA5 gene, fat intake did not impact overall body mass (BMI). In other words, the estimated 13% of the population with this gene can eat what most would consider to be an unhealthy diet and still maintain a generally healthy weight. Although this finding is not directly related to the genetic causes of obesity, it does suggest that a strong link does exist between genetics, our physique, and the ease with which we can (or can?t) maintain a healthy weight.

Nature and Nurture

Although these recent findings suggest that there is a strong link between genetics and obesity, don?t despair. As scientists would be the first to remind you, even if you have the genes that increase your risk for a condition, that doesn?t mean you?re doomed to a lifelong struggle with weight gain. Genetic expression results from a combination of our DNA and our daily choices.

In other words, if you maintain a reasonably healthy diet and exercise regularly, you probably won?t become overweight, even if you are genetically predisposed to it. As with so many things in life, if you stick to a path of moderation, you can decide your own destiny.