It was a joke when I was a nutrition undergrad (in England, graduated in 1987) that we had three years of intense human nutrition education and medical doctors were lucky to get eight hours. And yet who did people go to for dietary advice?
In 1985, the National Academy of Sciences found that an average of 21h of nutritional training was offered and that:
" Nutritional education programs in US medical schools are largely inadequate to meet the present and furture demands of the medical professions."
An article in NutraIngredients,USA suggests that things haven't improved much since. A recent survey of 106 American medical schools showed an average of 23.9h (see figure below) of nutritional education; most of this was in the first two years, with nutrition intergrated into basic science classes. Only 30 percent of medical schools surveyed required a separate nutrition course. This is an hour short of the American Society for Clinical Nutrition 1989 recommendation of 25h.
Adams, K. M.; Lindell, K. C.; Kohlmeier, M.; Zeisel, S. H. Status of nutrition education in medical schools. Am J Clin Nutr 2006, 83, 941S-944S.