Plasma n -3 fatty acids and psychological distress in aboriginal Cree Indians (Canada)

Health measures of Eeyouch (Cree) who are eligible to participate in the on-the-land Income Security Program in Eeyou Istchee (northern Quebec, Canada)

BACKGROUND

Participation in on-the-land programs that encourage traditional cultural activities may improve health and well-being. The Income Security Program (ISP) - a financial incentive-based on-the-land program - for Eeyouch (Cree) hunters and trappers in Eeyou Istchee was created as a result of the 1975 James Bay and Northern Quebec Agreement to help mitigate the effects of hydroelectric development on the Cree people of northern Quebec, Canada. Beyond the ISP's financial incentives, little is known about the health measures of those who are eligible to participate in the ISP (i.e. spent ≥120 days on-the-land during the previous year). Therefore, this paper's objective was to assess the health measures of northern Quebec Cree, who were eligible for participation in the ISP.

METHODS

Using participant data (n = 545) compiled from the Nituuchischaayihtitaau Aschii Multi-Community Environment-and-Health Study, we assessed 13 different health measures in generalized linear models with the independent variable being the eligibility to participate in the ISP.

RESULTS

Participants in the present study who were eligible for the ISP had significantly higher levels of vigorous and moderate activity per week, and higher concentrations of omega-3 polyunsaturated fatty acids in the blood compared to those ineligible for the ISP (i.e. spent ≤119 days on-the-land during the previous year). Encouragingly, following model adjustment for age and sex, participants eligible for the ISP did not have higher blood concentrations of mercury than those who were not eligible for the ISP.

CONCLUSIONS

Our results suggest that the participants eligible for participation in the ISP are likely to be healthier than those who are ineligible to participate - and are promising for on-the-land programs for Indigenous peoples beyond a financial incentive - with no apparent higher risk of increasing contaminant body burden through traditional on-the-land-activities (e.g. fish consumption).

The mental health of Indigenous peoples in Canada: A critical review of research

Many scholars assert that Indigenous peoples across the globe suffer a disproportionate burden of mental illness. Research indicates that colonialism and its associated processes are important determinants of Indigenous peoples' health internationally. In Canada, despite an abundance of health research documenting inequalities in morbidity and mortality rates for Indigenous peoples, relatively little research has focused on mental health. This paper provides a critical scoping review of the literature related to Indigenous mental health in Canada. We searched eleven databases and two Indigenous health-focused journals for research related to mental health, Indigenous peoples, and Canada, for the years 2006-2016. Over two hundred papers are included in the review and coded according to research theme, population group, and geography. Results demonstrate that the literature is overwhelmingly concerned with issues related to colonialism in mental health services and the prevalence and causes of mental illness among Indigenous peoples in Canada, but with several significant gaps. Mental health research related to Indigenous peoples in Canada overemphasizes suicide and problematic substance use; a more critical use of the concepts of colonialism and historical trauma is advised; and several population groups are underrepresented in research, including Métis peoples and urban or off-reserve Indigenous peoples. The findings are useful in an international context by providing a starting point for discussions, dialogue, and further study regarding mental health research for Indigenous peoples around the world.

Global survey of the omega-3 fatty acids, docosahexaenoic acid and eicosapentaenoic acid in the blood stream of healthy adults

Studies reporting blood levels of the omega-3 polyunsaturated fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), were systematically identified in order to create a global map identifying countries and regions with different blood levels. Included studies were those of healthy adults, published in 1980 or later. A total of 298 studies met all inclusion criteria. Studies reported fatty acids in various blood fractions including plasma total lipids (33%), plasma phospholipid (32%), erythrocytes (32%) and whole blood (3.0%). Fatty acid data from each blood fraction were converted to relative weight percentages (wt.%) and then assigned to one of four discrete ranges (high, moderate, low, very low) corresponding to wt.% EPA+DHA in erythrocyte equivalents. Regions with high EPA+DHA blood levels (>8%) included the Sea of Japan, Scandinavia, and areas with indigenous populations or populations not fully adapted to Westernized food habits. Very low blood levels (≤4%) were observed in North America, Central and South America, Europe, the Middle East, Southeast Asia, and Africa. The present review reveals considerable variability in blood levels of EPA+DHA and the very low to low range of blood EPA+DHA for most of the world may increase global risk for chronic disease.

Omega-3 fatty acids and brain resistance to ageing and stress: body of evidence and possible mechanisms

The increasing life expectancy in the populations of rich countries raises the pressing question of how the elderly can maintain their cognitive function. Cognitive decline is characterised by the loss of short-term memory due to a progressive impairment of the underlying brain cell processes. Age-related brain damage has many causes, some of which may be influenced by diet. An optimal diet may therefore be a practical way of delaying the onset of age-related cognitive decline. Nutritional investigations indicate that the ω-3 poyunsaturated fatty acid (PUFA) content of western diets is too low to provide the brain with an optimal supply of docosahexaenoic acid (DHA), the main ω-3 PUFA in cell membranes. Insufficient brain DHA has been associated with memory impairment, emotional disturbances and altered brain processes in rodents. Human studies suggest that an adequate dietary intake of ω-3 PUFA can slow the age-related cognitive decline and may also protect against the risk of senile dementia. However, despite the many studies in this domain, the beneficial impact of ω-3 PUFA on brain function has only recently been linked to specific mechanisms. This review examines the hypothesis that an optimal brain DHA status, conferred by an adequate ω-3 PUFA intake, limits age-related brain damage by optimizing endogenous brain repair mechanisms. Our analysis of the abundant literature indicates that an adequate amount of DHA in the brain may limit the impact of stress, an important age-aggravating factor, and influences the neuronal and astroglial functions that govern and protect synaptic transmission. This transmission, particularly glutamatergic neurotransmission in the hippocampus, underlies memory formation. The brain DHA status also influences neurogenesis, nested in the hippocampus, which helps maintain cognitive function throughout life. Although there are still gaps in our knowledge of the way ω-3 PUFA act, the mechanistic studies reviewed here indicate that ω-3 PUFA may be a promising tool for preventing age-related brain deterioration.

Plasma omega 3 polyunsaturated fatty acid status and monounsaturated fatty acids are altered by chronic social stress and predict endocrine responses to acute stress in titi monkeys

Disturbances in fatty acid (FA) metabolism may link chronic psychological stress, endocrine responsiveness, and psychopathology. Therefore, lipid metabolome-wide responses and their relationships with endocrine (cortisol, insulin, and adiponectin) responsiveness to acute stress (AS) were assessed in a primate model of chronic social stress (CS). Compared to controls (not exposed to CS), CS increased (P≤0.05) circulating triacylglycerol (TG) and phosphatidylethanolamine (PE) n-6/n-3 and reduced (P≤0.05) cholesterol ester (CE) 16:1n7 and phosphatidylcholine (PC) 18:1n7, suggesting lower omega-3 FA status and stearoyl-CoA desaturase activity, respectively. Cortisol responses to AS positively correlated with TG n-6/n-3 (r=0.93; P=0.007), but only in CS monkeys. The adiponectin response to AS inversely correlated with CE n-6/n3 (r=-0.89; P=0.045) and positively with TG 16:1n7 (r=0.98; P=0.004), only in CS monkeys. Our results are consistent with previously reported FA profiles in stress-related psychopathology and suggest that compositional changes of specific lipid FAs may form new functional markers of chronic psychological stress.