New 'obesity calculator' predicts child's likelihood of being overweight Childhood obesity has been on the rise in the United States, a trend that is putting many children at risk for a multitude of health problems - from cardiovascular disease and high blood pressure to early type 2 diabetes. For parents looking to keep their child healthy and physically fit as they grow up, a better understanding of their child's propensity towards obesity could be an essential tool in helping to keep off the pounds. But how are parents supposed to know the likelihood their child will be overweight? A new, simple formula could be the key. Available as an online calculator, an equation developed by researchers at the Imperial College London can strongly predict a baby's probability of becoming obese during childhood. Utilizing simple data such as the child's birth weight, number of household members and the mother and father's body mass indexes (BMI), the calculator provides a percentage of predicted probability of obesity. The mother's occupation and her gestational smoking habits are also taken into consideration. Take a hypothetical couple with BMIs of 25, the mother a non-smoker working a professional job, both living in a two-person household: If they just gave birth to a nearly 8-pound baby, the likelihood of their child being overweight or obese is only 2.05 percent. However, once you change the mother's occupation from a professional job to unskilled or unemployed, the child's likelihood jumps up to 14.25 percent. Click to use the calculator. Environmental and lifestyle factors To develop the formula, researchers analyzed data from an ongoing 1986 study following 4,000 children born in Finland over the course of their lives. They originally examined a variety of different factors that could potentially explain the population's obesity - from genetic variants to environmental and lifestyle factors. "We were basically looking at correlations between different factors, how they all come together and what was the predictive value in this analysis," Marjo-Riita Jarvelin, one of the study's lead authors, told FoxNews.com. ..."Once we add one extra factor, does it improve the model? If you add paternal BMI, does it improve? Then, when you add in maternal smoking, does it improve again? And so on, and so on. Eventually, you will end up with a situation where adding something like maternal age does not improve the model. It's inclusion and exclusion. According to Jarvelin, the researchers were able to narrow down the most predictive factors to these few lifestyle and environmental factors, which were able to accurately predict childhood obesity up to 85 percent of the time. While initially tested and analyzed, genetic variations associated with obesity were ultimately not very reliable in predicting a child's probability of obesity. "Once we compare different statistical models, and we added the genetic variants [associated with causing obesity], their ability to explain childhood obesity didn't improve at all in practice," Jarvelin, a pediatrician and professor and chair in Lifecourse Epidemiology at Imperial College London, told FoxNews.com. Genetic variants were not important at a population level to help explain common obesity in a population. Jarvelin added that these environmental factors are more important than genetic variants. "This doesn't exclude the impact of genetics when it comes to obesity," - about one in 10 cases of obesity resulted from a rare genetic mutation - "but, if we are looking at it population-wise in the development of childhood obesity, it's very small proportionally." Jarvelin noted that of the kids tested with the obesity calculator, the 20 percent with the highest likelihood of obesity at birth made up 80 percent of obese children. A growing problem Childhood obesity has become a growing dilemma in developed nations and most notably in the United States, with rates more than tripling in the past 30 years. According to the U.S. Centers for Disease Control and Prevention, more than one-third of American children were overweight or obese in 2008. When it comes to solving the obesity crisis, Jarvelin, along with many other pediatricians argue that prevention is the biggest defense - through healthy lifestyle habits and physical activity. She noted that since the data needed for the calculator are routinely measured during maternity care, the calculator can be a cheap and valuable resource for parents hoping to prevent their child from becoming overweight. "If you, for example, use this calculation model, and then you find out that your child's risk of becoming obese or overweight is at 70 percent, then we can say for sure that something should be done," Jarvelin said. The prevention of obesity should be started as early as possible. If child is obese at the age of 6 or 7, it's difficult to make the child lose weight. You have to work really, really hard. "I've seen families work hard to change their child's eating habits, but these should be started much earlier," Jarvelin continued. It's not just what the child eats, but their eating habits and, for example, how mothers and fathers are feeding their children when they are small. I've seen so many different feeding styles. It's incredible what parents can do. Click to use the calculator to determine a child's probability of being obese based on a Finnish population. Click to download the Excel spreadsheet, to determine a child's probability of being obese based on an American population. Once the sheet is open, click on the Viva tab.