Excellent paper on the limitations of applying laboratory-based dietary research to “the real world of humans.”  Highly recommended — avail through UNM access.

“It was found that genetic influences permeate all aspects of ingestive behavior. Not only body size was affected by inheritance, but also the amount eaten and the macronutrients and alcohol composition were affected.89–91 In fact, 65% of the variance in daily energy intake, 44% of the variance in meal frequency, 65% of the variance in average meal size could be attributed to heredity. In contrast, the analysis indicated that the shared familial environ- ments in which the twins were raised had no significant impact on the levels or pattern of intake in adulthood. A possible alternative explanation for these apparent genetic effects is that what is inherited is body size and that body size influences the amount of intake. However, linear-structural modeling showed (Fig. 11) that the heritability of daily food energy and macronutrient intake were independent of body size.91 Heredity accounted for 42% of the variance in daily intake even when the influence of body size was extracted in the model.”  — de Castro. 

Eating behavior: lessons from the real world of humans. Nutrition (2000) vol. 16 (10) pp. 800-13