Most of you have a general idea of what you would like to weigh and some of you may have a specific number in mind. Your view develops from health information, the media, fashion ideals, looking at other people, and considering what you used to weigh. The messages we receive about weight imply that we should simply pick a number and diet to get there. However, the more I read about metabolism and eating, the more I understand that we have a genetically programmed weight we are meant to be, that is, a range below and above which it is hard to go. The best indicator of what your range might be is to look at your family, because the latest research tells us that 50-70% of weight is genetically determined.

I can already hear the sighs of dismay and the shouts (maybe some curses too) of denial—50-70% is a huge chunk of programming. However, just because you don’t like a fact doesn’t make it untrue. You still have a 30-50% window to work in. What you eat, your stress level and how you manage stress, your age, lifestyle, amount and type of exercise, and general health all play a part in whether you will be at the top or bottom of the range. And, remember, it’s normal and natural to fluctuate within a weight span.

Even knowing that you will most likely have the body type and weight of your relatives is not simple. You also have to consider which family members you take after: your willowy mother, your beefy dad, your stocky grandfather, or your petite grandmother? The particular genetic package you inherit makes a difference, which is why you often find a pair of sisters or brothers in which one has weight struggles and the other doesn’t. Much of your physiology is simply the luck (or lack of it) of the draw.

Now, those of you with an all-or-nothing mentality—also called black-and-white thinking—may read my words and despair. If you can’t control how thin you want to be because of genetic programming, you might want to give up. Please, don’t. The window of opportunity you have is what makes the difference, especially to your health. What you do with that window in terms of staying fit and healthy plays a major part in determining well being and life expectancy. Remember, just because you don’t have complete control over what you weigh, doesn’t make it okay to relinquish control over the areas you can do something about. The way to find a comfortable weight is to work on becoming a “normal” eater. When your eating is consistently guided by hunger, enjoyment, satisfaction, and fullness, your body will settle within a range that is healthy and maintainable.