Bryna Shatenstein

Specific fatty acids and human colorectal cancer: an overview

BACKGROUND Evidence suggests that dietary fats are associated with risk of colorectal cancer. The effect of fats depends not only on the quantity, but also on their composition in specific fatty acids. Moreover, fats are peroxidizable, and peroxidation products as well as antioxidants play a role in the pathogenic process of colorectal cancer. METHODS The published literature was reviewed for the relationship between dietary intake or concentration of specific fatty acids in adipose tissue, erythrocytes, plasma or feces in relation to colorectal cancer. RESULTS Increased concentrations of short-chain fatty acids (SCFAs) and eicosanopentaenoic acid (EPA) seem to protect against colorectal cancer. Increased concentrations of medium-chain fatty acids (MCFAs) and arachidonic acid (AA) might be associated with increased risk. Long-chain saturated fatty acids (LCSFAs) seem unrelated to colorectal cancer, while the associations between monounsaturated fatty acids (MUFAs), trans fatty acids, polyunsaturated fatty acids (PUFAs) such as linoleic acid (LA), alpha-linolenic acid (ALA), docosahexaenoic acid (DHA), omega-3/omega-6 ratio and colorectal cancer are unconvincing. CONCLUSIONS It is suggested that the substitution of food with high MCFAs and AA content by a SCFAs- and EPA-rich diet may contribute to reduced risk of colorectal cancer.

An international trial of antioxidants in the prevention of preeclampsia (INTAPP).

OBJECTIVE We sought to investigate whether prenatal vitamin C and E supplementation reduces the incidence of gestational hypertension (GH) and its adverse conditions among high- and low-risk women. STUDY DESIGN In a multicenter randomized controlled trial, women were stratified by the risk status and assigned to daily treatment (1 g vitamin C and 400 IU vitamin E) or placebo. The primary outcome was GH and its adverse conditions. RESULTS Of the 2647 women randomized, 2363 were included in the analysis. There was no difference in the risk of GH and its adverse conditions between groups (relative risk, 0.99; 95% confidence interval, 0.78-1.26). However, vitamins C and E increased the risk of fetal loss or perinatal death (nonprespecified) as well as preterm prelabor rupture of membranes. CONCLUSION Vitamin C and E supplementation did not reduce the rate of preeclampsia or GH, but increased the risk of fetal loss or perinatal death and preterm prelabor rupture of membranes.

Underreporting of energy intake from a self-administered food-frequency questionnaire completed by adults in Montreal

BACKGROUND Energy intake determined from self-reported dietary assessment methods may be underreported. Therefore, it is important that such methods be validated against another with known validity for energy intake or energy expenditure. METHODS We investigated potential underestimation of energy intake obtained from our semi-quantitative food-frequency questionnaire (FFQ) administered between 2000 and 2001 in the metropolitan area of Montreal, Canada. The study population included 246 adults aged 18 to 82 years. The ratio of energy intake to estimated basal metabolic rate (EI/BMR) was used to assess underreporting and physical activity was determined from self-administered questions. Comparison of the EI/BMR ratio with the Goldberg statistical cut-off allowed us to detect individuals who were low energy reporters (LERs). LERs and non-LERs were compared to determine if they differed on sociodemographic, anthropometric and lifestyle variables. RESULTS The EI/BMR ratio was 1.26 for men and 1.32 for women. LERs represented 43% of the sample of individuals. Male LERs accounted for 54% compared with 35% among females. Underreporting of energy intake was highest in men and individuals who were older, heavier, with higher body mass index and lower education level. A higher proportion of male LERs perceived their financial situation as adequate while a greater proportion of female LERs considered themselves poor. CONCLUSION Our data suggest that underreporting of energy intake from the FFQ was considerable and may bias dietary interpretation. As this was uneven across the sample, it is crucial to recognise the characteristics of LERs in order to increase the validity of reported energy intake.

Development and validation of a food frequency questionnaire.

Regular diet monitoring requires a tool validated in the target population. A 73-item, semiquantitative, self-administered food frequency questionnaire (FFQ), was adapted in French and English from the Block National Cancer Institute Health Habits and History Questionnaire. The FFQ was used to capture usual long-term food consumption among adults living in Quebec. A representative sample of adults aged 18 to 82 (57% female) was recruited by random digit dialling in the Montreal region. Approximately 64% of recruits completed and returned the instrument by mail (n=248). The FFQ was validated in a subsample (n=94, 61% female) using four nonconsecutive food records (FRs). Median energy intakes (in kcal) for men and women, respectively, were FFQ (total sample) 2,112 and 1,823, FFQ (subsample) 2,137 and 1,752, and FR (subsample) 2,510 and 1,830. Spearman correlation analyses between FFQ and FR nutrients were positive (with r ranging from 0.32 for folate to 0.58 for saturated fatty acids) and statistically significant (p<0.001), with better results among women. On average, cross-classification of energy and 24 nutrients from the FFQ and means of four FRs placed 39% into identical quartiles and 78% into identical and contiguous quartiles, with only 4% frankly misclassified. These results suggest that the FFQ is a relatively valid instrument for determining usual diet in Quebec adults.Regular diet monitoring requires a tool validated in the target population. A 73-item, semiquantitative, self-administered food frequency questionnaire (FFQ), was adapted in French and English from the Block National Cancer Institute Health Habits and History Questionnaire. The FFQ was used to capture usual long-term food consumption among adults living in Quebec. A representative sample of adults aged 18 to 82 (57% female) was recruited by random digit dialling in the Montreal region. Approximately 64% of recruits completed and returned the instrument by mail (n=248). The FFQ was validated in a subsample (n=94, 61% female) using four nonconsecutive food records (FRs). Median energy intakes (in kcal) for men and women, respectively, were FFQ (total sample) 2,112 and 1,823, FFQ (subsample) 2,137 and 1,752, and FR (subsample) 2,510 and 1,830. Spearman correlation analyses between FFQ and FR nutrients were positive (with r ranging from 0.32 for folate to 0.58 for saturated fatty acids) and statistically sign...Regular diet monitoring requires a tool validated in the target population. A 73-item, semiquantitative, self-administered food frequency questionnaire (FFQ), was adapted in French and English from the Block National Cancer Institute Health Habits and History Questionnaire. The FFQ was used to capture usual long-term food consumption among adults living in Quebec. A representative sample of adults aged 18 to 82 (57% female) was recruited by random digit dialling in the Montreal region. Approximately 64% of recruits completed and returned the instrument by mail (n=248). The FFQ was validated in a subsample (n=94, 61% female) using four nonconsecutive food records (FRs). Median energy intakes (in kcal) for men and women, respectively, were FFQ (total sample) 2,112 and 1,823, FFQ (subsample) 2,137 and 1,752, and FR (subsample) 2,510 and 1,830. Spearman correlation analyses between FFQ and FR nutrients were positive (with r ranging from 0.32 for folate to 0.58 for saturated fatty acids) and statistically sign...

Low Vitamin K Intakes in Community-Dwelling Elders at an Early Stage of Alzheimer's Disease

An increasing body of evidence points to a role for vitamin K in brain physiology through its participation in sphingolipid metabolism and biological activation of the vitamin K-dependent protein Gas6. One hypothesis is that vitamin K may also play a role in the pathogenesis of Alzheimers disease. A recent study found that patients with early-stage Alzheimers disease consumed less vitamin K than did cognitively intact control subjects. To learn more about the dietary intakes and food sources of vitamin K in these patients, a detailed analysis was conducted. Dietary vitamin K intakes were assessed from 5 nonconsecutive days of food records collected from 31 community-dwelling patients with early-stage Alzheimers disease and in 31 age- and sex-matched cognitively intact control subjects. Mean vitamin K intake on a person-day basis was 63+/-90 microg/day in patients and 139+/-233 microg/day in control subjects. Vitamin K intakes were significantly less in participants with Alzheimers disease (P<0.0001), even after adjusting for energy intakes (P=0.0003). Vegetables, fats, and fruits contributed more than 70% of total vitamin K intake in both groups. The main source of vitamin K was green vegetables, which contributed 33% and 49% to total intakes in patients and control subjects, respectively. This lower consumption of green vegetables in participants with Alzheimers disease explained their lower vitamin K intakes overall. Despite their limitations, results are in line with the most recent research in both vitamin K and Alzheimers disease and suggest a need to consider vitamin K in future investigations on the role of diet in Alzheimers disease.

The influence of dairy products on plasma uric acid in women.

Elevated levels of plasma uric acid have been linked to increased risk of cardiovascular diseases and their complications. As dairy proteins have been found to decrease plasma uric acid without increasing glomerular filtration rate, a sample of postmenopausal women living in Montreal was studied to investigate the nature of this relationship. Participants (158 Roman Catholic nuns) were randomly assigned to one of two test diets for a period of four weeks: the dairy foods group (n=81) consumed approximately 30 grams of dairy protein daily and the dairy-free diet group (n=77) ate no dairy foods at all. Subjects completed two one-day food records, a core questionnaire and a dairy foods diet history; blood specimens were obtained, and blood pressure, height and weight were measured. Average nutrient intakes differed as a consequence of the test diets, with significantly greater intakes of protein, fat, saturated fat, monounsaturated fat, potassium and calcium (p<0.01) in the dairy group after the study period, and lower dietary levels of protein, cholesterol, calcium and retinol (p<0.01) in the dairy-free group. Plasma uric acid was unchanged after the dietary intervention in the dairy group, but increased by 7.8 µmol/1 (p=0.03) in subjects on the dairy-free diet; however, diastolic blood pressure decreased in response to calcium (β=−22.9, SE=10.0,p=0.02) among those whose diet included dairy foods. The study results suggest that proteins of dairy origin may play a role in stabilising or lowering plasma uric acid, and that calcium or other components found in milk products may also reduce diastolic blood pressure. While these findings have implications for dietary prevention to decrease cardiovascular risk in postmenopausal women, further investigations should examine these mechanisms in men over the age of 50 to ascertain whether a similar response would occur.

Trajectories of Physical Function Decline and Psychological Functioning: The Québec Longitudinal Study on Nutrition and Successful Aging (NuAge)

BACKGROUND Decline of physical function with age is associated with substantial health consequences. Physical and psychological functioning is linked, but the temporal nature of this association remains unclear. METHODS Three-year follow-up data from men and women (n = 1,741), aged 68-82 years, in the longitudinal study on nutrition and successful aging (NuAge; Québec, Canada) were used. Growth curve modeling was performed to examine trajectories of a global physical performance score across time as conditioned by cognition and depression. RESULTS Significant decline in physical function was observed (p < .0001). Rate of decline in physical performance score was accelerated in the older participants (>77 years; age(2): p < .01) but not affected by slight decline in cognition or depression. Yet, people with lower cognition level and more depressive symptoms show lower physical capacity throughout the entire follow-up period (p < .0001). CONCLUSIONS Physical function significantly declined over 3 years, in particular in the oldest group. A subtle decline in psychological health paralleled decline in physical function but did not accelerate it.

Dietary risk factors for testicular carcinoma

Although testicular cancer is a relatively rare lesion, accounting for only 1.1% of all malignant neoplasms in males in Canada, it is the most common cancer among Canadian men 20–45 years of age. Knowledge of the causes of testicular cancer risk in general, and more specifically, its association with diet, remain limited. Data from 601 cases of testicular cancer and 744 population‐based controls collected in 8 of the 10 Canadian provinces between 1994–97 were used to explore the relationship between diet and testicular cancer risk. We systematically examined 17 food groups, 15 nutrients and 4 individual foods based on data collected through a 69‐item food‐frequency questionnaire. Our results suggest that high dairy product intake, in particular high intake of cheese (odds ratio [OR] = 1.87; 95% confidence interval [CI] 1.22–2.86; p‐trend < 0.001), is associated with an elevated risk of testicular cancer in Canadian males.

Diet and prostate cancer risk with specific focus on dairy products and dietary calcium: a case-control study.

Despite the prevalence of prostate cancer worldwide, only a few risk factors have been well‐established. The role of diet, especially of dairy products, in the etiology of prostate cancer is still controversial.

Maternal and fetal leptin, adiponectin levels and associations with fetal insulin sensitivity

It remains uncertain whether leptin and adiponectin levels are correlated in maternal vs. fetal circulations. Little is known about whether leptin and adiponectin affect insulin sensitivity during fetal life.