If you’re searching for reasons why you have difficulty losing weight, you may have to look back all the way to childhood. According to an interesting new study, what you ate as a young child may have a direct impact on your risk of being overweight or obese as an adult. Those greasy hamburgers you enjoyed so much as a small tyke may be spelling trouble for you today when it comes to your weight. If this is true, childhood diet may play an even more important role than previously realized in determining whether a child will be obese as an adult.

This landmark study, which was published in the Journal of Physiology, was conducted on a group of three rats. As very young rats, each group was fed a different diet. One group received a high fiber diet, another received a high protein diet, while the third was a control group. As the matured, they were switched over to the classic “American diet” consisting of high carbohydrate, high fat foods. The researchers carefully recorded their weights and body fat. To the surprise of the researchers, this study clearly showed that rats reared on the high protein diet gained the most weight, while the ones receiving the healthier high fiber diet gained the least. The rats on the high fiber diet also put on the least amount of body fat compared to the other two groups.

Why was childhood diet so important in determining the future weight of these test rats? Although the answer isn’t completely known, the researchers speculate that childhood diet affects certain genes responsible for controlling body weight, effectively turning them off or on based on the type of foods eaten. The genes being turned on or off could affect the level of hormones that control satiety and metabolism later in life.

This is one of the first studies to show that what you eat as a child may come back to haunt you later. If this is the case, childhood diet becomes even more important in terms of determining future health. By giving children a nutritious lower calorie diet, you would be laying the foundation for a healthier adulthood. In contrast, a diet of fast foods and typical, Americanized offerings could spell trouble later in terms of body weight and health in general.

If this study holds true, it’s another compelling reason to be urge parents to offer a healthy childhood diet to their kids rather than the calorie laden, high fat meals many children eat on a daily basis. Giving calorie rich foods at an early age may put a child at a weight disadvantage for the rest of their life; and no parent wants that.