Djungarian hamsters ( Phodopus sungorus) acclimated to a short photoperiod (8:16-h light-dark cycle) display spontaneous daily torpor with ad libitum food availability. The time course of body temperature (Tb), metabolic rate, respiratory quotient (RQ), and substrate and enzyme changes was measured during entrance into torpor and in deep torpor. RQ, blood glucose, and serum lipids are high during the first hours of torpor but then gradually decline, suggesting that glucose is the primary fuel during the first hours of torpor, with a gradual change to lipid utilization. No major changes in enzyme activities were observed during torpor except for inactivation of the pyruvate dehydrogenase (PDH) complex in liver, brown adipose tissue, and heart muscle. PDH inactivation closely correlates with the reduction of total metabolic rate, whereas in brain, kidney, diaphragm, and skeletal muscle, PDH activity was maintained at the initial level. These findings suggest inhibition of carbohydrate oxidation in heart, brown adipose tissue, and liver during entrance into daily torpor.

Research conducted in the mid-1990s indicated that the levels of Trans fats in Canadian diets were among the highest in the world. The consumption of Trans fats raises blood levels of low-density lipoprotein (LDL)-cholesterol, while reducing levels of high-density lipoprotein (HDL)-cholesterol. In June 2007, Health Canada called on the food industry to voluntarily reduce levels of Trans fats in vegetable oils and soft (tub)-margarines to <2 of total fat, and in all other foods, to <5. Industry must show satisfactory progress by June 2009, or Health Canada might have to introduce legislation to ensure that recommended limits are achieved. Since 2005, Health Canada has been performing a national assessment of prepackaged and restaurant foods that likely contain Trans fats. From 2005 to 2009, 1120 samples were analyzed, of which 852 or approximately 76 met the recommended Trans fat limits. As a result of reformulation, most of the products had decreased Trans + saturated fat content. The estimated average intake of Trans fatty acids (TFA) in Canada significantly dropped from the high value of 8.4 g/day in the mid-1990s to 3.4 g/day (or 1.4 food energy) in 2008. However, this TFA intake of 1.4 of energy is still above the World Health Organization recommended limit of TFA intake of <1 of energy, which suggests that the Canadian food industry needs to put more effort into reducing the TFA content in its products, especially in tub-margarines, donuts, and bakery products.

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Liver folate is considered to be a direct measure of body folate stores. Specimens of 560 livers were therefore collected during autopsies at hospitals in seven cities across Canada, and analyzed for "total" folate. The values obtained ranged from 2.7 to 15.6 micrograms/g. Stillborn infants had the lowest mean liver folate levels (5.9 microgram/g). Mean liver folate levels tended to increase from birth to a peak between 11 to 30 years (8.8 micrograms/g), and then decreased with increasing age. This trend was reflected in an increased proportion (6 to 15%) of folate levels in the 3.1 to 5.0 microgram/g range in older subjects. Liver folate levels of male subjects did not differ from those of females. Mean liver levels tended to be slightly higher, and the number of liver levels between 3.1 to 5.0 micrograms/g was lower, in subjects dying accidentally (7.8%) and from heart and coronary disease (8.7%), than in those dying from cancer, respiratory diseases or other causes (11.7 to 15.3%). Only two subjects had liver folate levels below 3 microgram/g. In this survey, there was thus little evidence of severe folate deficiency.