The nutritional intakes of 250 ultra-orthodox adults from Hassidic Jewish sects (the majority of sects living in Outremont in central MontrealversusLubavitcher Hassidim) were assessed as part of a Montreal study examining the influence of the Jewish religion and dietary laws (kashruth) on family food habits. Each participant completed a self-administered, mailed questionnaire, providing information on country of origin, marital, work and educational status, some health-relevant behaviours, and self-reported personal and family history of selected chronic diseases; a two-day food record attached to this questionnaire was employed to evaluate week-day and sabbath nutrient levels. Body mass index was high among older women and younger men. While Lubavitchers were significantly better educated than their Outremont counterparts, they reported more adherence to therapeutic diets, and greater frequencies of smoking, cardiovascular and cerebrovascular diseases, with a trend for cancer; Outremont sects showed a trend for more regular exercise. The nutrient analyses revealed intakes which differed from those of French-Canadian Montrealers and Canadians in general, as well as an American sample, mainly due to lower energy, fat, and saturated fat intakes in the Hassidic group. Levels of protein, carbohydrates, iron and potassium were similar to Quebec and Canadian findings, while higher vitamin C, polyunsaturated fat and cholesterol were noted among the Hassidim. Most Canadian recommended nutrient intakes (RNIs) were met or exceeded; however, pantothenic acid and copper fell below the two-thirds‘caution point’, and total fibre, zinc, vitamin D and calcium were between only 68 and 79% of their respective recommendations. Differences were observed between sabbath and week-day intakes as proportions of the RNIs, and between the Hassidic sects studied. The results suggest that sect-related differences in diet, and the resultant nutrient intakes, are related to the observed differences in health behaviour and self-reported history of disease. Further study is required to clarify these issues.