although its an interesting theory it's not supported by science. lactose intolerance does not cause weight gain. excess weight occurs when you eat more calories than your body burns. in fact people with more serious gastrointestinal problems like ulcerative colitis or crohns have food rush through them and they tend to be underweight and sometimes malnourished. the body does not seem to overcompensate.
can lactose intolerance cause weight gain? if all my food rushes through could my body be overdoing calorie retention? . if all the food i eat constantly rushes through could my body be overcompensating and desperately trying to get calories out of food because it usually 'rushes' out? . i've timed my body before and high-lactose items last 15 minutes (until desperate release). this sounds like the gi may have to be in high gear just to try to absorb food. if it's in this gear when i don't have lactose i feel it may be a reason for weigh gain or retention.