Dietary intake and body mass index of adults in 2 Ojibwe communities

Importance of the traditional food systems for First Nations adults living on reserves in Canada

OBJECTIVE

To describe the traditional food (TF) systems of First Nations in Canada, including intake, barriers and promoters.

METHODS

The First Nations Food, Nutrition and Environment Study is a cross-Canada participatory study of First Nations adults below the 60th parallel that obtained data for communities excluded from other national studies. A food frequency questionnaire was used to establish frequency of TF intake (number of days in a year) to allow comparisons across ecozones/regions in Canada. Grams of TF intake were also calculated using frequency multiplied by average portions from 24-h recalls. Closed- and open-ended questions attempted to identify some of the key barriers and concerns regarding TF access and use. Multivariable analyses were run to determine what factors are associated with increased TF consumption.

RESULTS

Across communities, there is a strong preference by adults to have TF in the diet more often. Consumption of land animals was most frequently reported in most ecozones except for the Pacific Maritime and Mixedwood Plains, where fish and plants, respectively, were more frequently consumed. First Nations identified structural and environmental challenges such as development, government regulations and climate change, along with household barriers such as insufficient capital for equipment and transportation, lack of time and absence of a hunter in the household. Multivariable analyses revealed that the highest intake of TF occurred in the Taiga Plains ecozone, and for older individuals and men.

CONCLUSION

Identifying solutions that empower First Nations at all levels is required to overcome the multiple challenges to the inclusion of TF in the diet.

Host-microbial interactions in the metabolism of different dietary fats

Although generally presumed to be isocaloric, dietary fats can differ in their energetic contributions and metabolic effects. Here, we show how an explicit consideration of the gut microbiome and its interactions with human physiology can enrich our understanding of dietary fat metabolism. We outline how variable human metabolic responses to different dietary fats, such as altered ileal digestibility or bile acid production, have downstream effects on the gut microbiome that differentially promote energy gain and inflammation. By incorporating host-microbial interactions into energetic models of human nutrition, we can achieve greater insight into the underlying mechanisms of diet-driven metabolic disease.

Biocultural Hysteresis Inhibits Adaptation to Environmental Change

Indigenous peoples and local communities (IPLC) often use natural resources as both a reason and mechanism for environmental management, yet a number of environmental, social, and economic drivers disrupt this relationship. Here, we argue that these drivers can also trigger a set of feedback mechanisms that further diminish the efficacy of local management. We call this process biocultural hysteresis. These feedbacks, which include knowledge loss and a breakdown of social hierarchies, prevent IPLC from adapting their management to change. Biocultural hysteresis worsens as IPLC spend an increasing amount of time outside their social-ecological context. Therefore, we argue for adaptive policies and processes that favour protecting and enabling IPLC engagement with their environment.

The implementation of a participatory manuscript development process with Native American tribal awardees as part of the CDC Communities Putting Prevention to Work initiative: challenges and opportunities

OBJECTIVE

In 2009, the Centers for Disease Control and Prevention funded 50 communities, including three tribal awardees, to implement environmental approaches to address obesity and smoking through the Communities Putting Prevention to Work initiative. The tribes were among the selected awardees offered training support for analyzing, writing, and publishing their findings. This article describes the process of translating the workshops, guided by a participatory framework, for implementation with the tribes.

METHODS

Nine participants from three tribes attended the workshops in Decatur, Georgia, in August and October of 2012: 1) a one-day pre-conference workshop focused on integrating both Indigenous and academic evaluation methods; 2) a 4 day data analysis workshop; and 3) a 5 day scientific writing workshop. Participants were provided with technical assistance following the workshops.

RESULTS

Participants viewed the workshops positively and have continued to develop their manuscripts. To date one tribal awardee has submitted their manuscript for publication.

CONCLUSION

The participatory manuscript development process described here is the first of its kind outlining a pathway for tribal community health practitioners to translate and publish their work. Further development of this process could increase the number of community-developed manuscripts, thereby advancing the field of translational intervention science and leading to improved health equity.

Interactive effects of dietary fat/carbohydrate ratio and body mass index on iron deficiency anemia among Taiwanese women

Whether being overweight or obese is associated with increased risk of iron deficiency anemia (IDA) remains controversial. We evaluated the dietary intakes and risk for IDA in relation to body mass index (BMI). One thousand two hundred and seventy-four females aged ≥19 years, enrolled in the third Nutrition and Health Survey in Taiwan (NAHSIT) 2005–2008, were selected. Half of the women were either overweight (24.0%) or obese (25.3%). The overall prevalence of anemia, iron deficiency and IDA among adult women was 19.5%, 8.6% and 6.2%. BMI showed a protective effect on IDA: overweight (odds ratio, OR: 0.365 (0.181–0.736)) and obese (OR: 0.480 (0.259–0.891)) when compared with normal weight. Univariate analysis identified increased IDA risk for overweight/obese women who consumed higher dietary fat but lower carbohydrate (CHO) (OR: 10.119 (1.267–80.79)). No such relationship was found in IDA women with normal weight (OR: 0.375 (0.036–4.022)). Analysis of interaction(s) showed individuals within the highest BMI tertile (T3) had the lowest risk for IDA and the risk increased with increasing tertile groups of fat/CHO ratio; OR 0.381 (0.144–1.008; p = 0.051), 0.370 (0.133–1.026; p = 0.056) and 0.748 (0.314–1.783; p = 0.513); for T1, T2 and T3, respectively. In conclusion, a protective effect of BMI on IDA may be attenuated in women who had increased fat/CHO ratio.

Modifiable cardiovascular disease risk factors among indigenous populations

Objective. To identify modifiable cardio-metabolic and lifestyle risk factors among indigenous populations from Australia (Aboriginal Australians/Torres Strait Islanders), New Zealand (Māori), and the United States (American Indians and Alaska Natives) that contribute to cardiovascular disease (CVD). Methods. National health surveys were identified where available. Electronic databases identified sources for filling missing data. The most relevant data were identified, organized, and synthesized. Results. Compared to their non-indigenous counterparts, indigenous populations exhibit lower life expectancies and a greater prevalence of CVD. All indigenous populations have higher rates of obesity and diabetes, hypertension is greater for Māori and Aboriginal Australians, and high cholesterol is greater only among American Indians/Alaska Natives. In turn, all indigenous groups exhibit higher rates of smoking and dangerous alcohol behaviour as well as consuming less fruits and vegetables. Aboriginal Australians and American Indians/Alaska Natives also exhibit greater rates of sedentary behaviour. Conclusion. Indigenous groups from Australia, New Zealand, and the United States have a lower life expectancy then their respective non-indigenous counterparts. A higher prevalence of CVD is a major driving force behind this discrepancy. A cluster of modifiable cardio-metabolic risk factors precede CVD, which, in turn, is linked to modifiable lifestyle risk factors.

Obesity and type 2 diabetes in Northern Canada's remote First Nations communities: the dietary dilemma

First Nations populations in Northwestern Ontario have undergone profound dietary and lifestyle transformations in less than 50 years, which have contributed to the alarming rise in obesity and obesity-related diseases, in particular type 2 diabetes mellitus. Even though the genetic background of First Nations peoples differs from that of the Caucasians, genetics alone cannot explain such a high prevalence in obesity and type 2 diabetes. Modifications in lifestyle and diet are major contributors for the high prevalence of chronic diseases. What remains constant in the literature is the persistent view that locally harvested and prepared foods are of tremendous value to First Nations peoples providing important health and cultural benefits that are increasingly being undermined by western-based food habits. However, the complexities of maintaining a traditional diet require a multifaceted approach, which acknowledges the relationship between benefits, risks and viability that cannot be achieved using purely conventional medical and biological approaches. This brief review explores the biological predispositions and potential environmental factors that contribute to the development of the high incidence of obesity and obesity-related diseases in First Nations communities in Northern Canada. It also highlights some of the complexities of establishing exact physiological causes and providing effective solutions.

Assessing health status, behavioral risks, and health disparities in American Indians living on the northern plains of the U.S

OBJECTIVE

We assessed health status and behavioral risks in American Indians (AIs) from rural, northern plains reservation communities.

METHODS

AI interviewers from the communities administered the core and optional modules of the Behavioral Risk Factor Surveillance System (BRFSS) to 404 AI adults randomly selected from housing lists from four AI tribal communities located on the northern plains of the U.S. The BRFSS interview assessed several health functioning areas including medical conditions, preventive screenings, and behavioral risks. We measured health disparities by comparing the AI sample data with a northern plains statewide (North Dakota) sample and a U.S. national sample. We compared outcomes with BRFSS statewide (North Dakota) and U.S. national data from telephone-based interviews.

RESULTS

AI participants showed a significantly greater prevalence of diabetes, coronary heart disease, myocardial infarction, smoking, obesity, and heavy alcohol use than either the regional or national samples. They also reported being less likely to engage in leisure-time physical activity and to have had age-appropriate preventive screenings for several diseases including colorectal cancer, prostate cancer, breast cancer, and cardiovascular disease.

CONCLUSIONS

Face-to-face interviews conducted by AI community members are an effective means of gathering health information about AIs living in rural, reservation communities. AIs living in these communities on the northern plains have a much higher prevalence of many health-risk behaviors and some medical conditions than are found in the general population. Improved health-care access, better preventive screenings, and culturally appropriate community-based health promotion programs and policies should be examined as possible ways to reduce health disparities.

Dietary intake and development of a quantitative FFQ for a nutritional intervention to reduce the risk of chronic disease in the Navajo Nation

OBJECTIVES

To characterize dietary intake for Navajo adults, to identify foods for a nutritional intervention programme and to develop a culturally appropriate quantitative FFQ (QFFQ) for evaluating the impact of the intervention programme.

DESIGN

A cross-sectional study was conducted using 24 h dietary recalls.

SETTING

Navajo Nation, USA.

SUBJECTS

Seventy-nine (forty men, thirty-nine women) aged 18-71 years completed 24 h dietary recalls.

RESULTS

The median daily energy intake was 11 585 kJ (2769 kcal) for men and 8519 kJ (2036 kcal) for women. The greatest contributors to energy were fried potato dishes, sweetened juices/drinks, regular pop, bread, tortillas and burritos (contributing approximately 30 % of total energy intake). The mean number of meat servings was over twice that recommended (2-3 servings recommended v. 7.4 consumed by men and 5.3 by women). The mean servings of vegetables were well below the recommendation of 3-5 servings (1.0 serving for men and 1.2 servings for women). The final QFFQ contains 177 food and drink items.

CONCLUSIONS

Our study found that major contributors to total energy, fat and sugar intakes in the Navajo Nation included mostly processed meats and sweetened drinks. A nutritional intervention will target these foods and promote acceptable and healthier alternatives. In addition, we were able to identify foods and beverages for inclusion on a culturally appropriate QFFQ to assess dietary intake. This QFFQ will be used to evaluate the effectiveness of our intervention on food and food group consumption and nutrient intake.

Assessing dietary intake in a population undergoing a rapid transition in diet and lifestyle: the Arctic Inuit in Nunavut, Canada

The aims of the present study were to (1) characterise the diets of adult Inuit; (2) highlight foods for a nutritional and lifestyle intervention programme; (3) develop a quantitative FFQ (QFFQ) to evaluate the programme and monitor changes in dietary intake in this population over time. A dietary survey using single 24-h dietary recalls was conducted among Inuit aged between 19 and 87 years in two communities in Nunavut, Canada. Eighty-seven subjects completed the recalls (response rate was approximately 73 %). The mean energy intake for men and women was 9530 and 6939 kJ, respectively. The intakes of dietary fibre and the majority of vitamins and minerals (especially vitamins A, D, and E, total folate and Ca) were far below the recommendations. Traditional foods contributed 40 and 42 %, respectively, to protein and Fe intakes. Non-nutrient-dense store-bought foods were consumed much more frequently than the nutrient-dense traditional foods. Foods high in fat and sugar were highlighted, and will be replaced by healthier, more nutrient-dense alternatives to address the dietary inadequacies for the nutritional intervention programme. A 154-item QFFQ was developed and pilot tested in the Arctic Inuit. The present study highlighted foods to be targeted for a nutritional and lifestyle intervention programme not previously undertaken in this population. This QFFQ is culturally appropriate and specific for evaluating the effectiveness of the programme, as well as monitoring nutritional transition in this population.

An exploratory spatial analysis of overweight and obesity in Canada

OBJECTIVE

The identification of spatial clusters of overweight and obesity can be a key indicator for targeting scarce public health resources. This paper examines sex-specific spatial patterns of overweight/obesity in Canada as well as investigates the presence of spatial clusters.

METHODS

Using data on Body Mass Index (BMI) from the 2005 Canadian Community Health Survey (20 years and older) cycle 3.1, a cross-sectional ecological-level study was conducted. Sex-specific prevalence of overweight and obesity were first mapped to explore spatial patterns. In order to assess the degree of spatial dependence, exploratory spatial data analysis was performed using the Moran's I statistic and the Local Indicator of Spatial Association (LISA).

RESULTS

Results revealed marked geographical variation in overweight/obesity prevalence with higher values in the Northern and Atlantic health-regions and lower values in the Southern and Western health-regions of Canada. Significant positive spatial autocorrelation was found for both males and females, with significant clusters of high values or 'hot spots' of obesity in the Atlantic and Northern health-regions of Alberta, Saskatchewan, Manitoba and Ontario.

CONCLUSIONS

Findings reveal overweight/obesity clusters and underscore the importance of geographically focused prevention strategies informed by population-specific needs.

The relationship of the burbot (Lota lota L.) to the reintroduction of off-the-land foods in the Sandy Lake First Nation Community

This article is based on a study of traditional lifestyle practices in the Sandy Lake First Nation community in northwestern Ontario, considering some of the benefits and risks of reintroducing off-the-land food sources, specifically as they relate to the burbot (Lota lota L). This article concentrates, therefore, on four avenues of exploration: (1) the "nutrition transition" in the First Nations population, (2) the meaning of a traditional diet in the Sandy Lake First Nation, (3) a nutritional value analysis of the burbot to determine its energy content and medicinal properties, and (4) the plausibility of reintroducing off-the-land food sources into the Sandy Lake First Nation community. We argue that though there may be health advantages to the reintroduction of off-the land food sources into First Nations contemporary diets, these benefits will be realized only if practiced according to historical dietary traditions drawing from critical parts of animal tissues to maximize nutrient intake.

Dietary intake and development of a quantitative food-frequency questionnaire for a lifestyle intervention to reduce the risk of chronic diseases in Canadian First Nations in north-western Ontario

Objectives

To characterise the diet of First Nations in north-western Ontario, highlight foods for a lifestyle intervention and develop a quantitative food-frequency questionnaire (QFFQ).

Design

Cross-sectional survey using single 24 h dietary recalls.

Setting

Eight remote and semi-remote First Nations reserves in north-western Ontario.

Subjects

129 First Nations (Oji-Cree and Ojibway) men and women aged between 18 and 80 years.

Results

The greatest contributors to energy were breads, pasta dishes and chips (contributing over 20 % to total energy intake). ‘Added fats’ such as butter and margarine added to breads and vegetables made up the single largest source of total fat intake (8·4 %). The largest contributors to sugar were sugar itself, soda and other sweetened beverages (contributing over 45 % combined). The mean number of servings consumed of fruits, vegetables and dairy products were much lower than recommended. The mean daily meat intake was more than twice that recommended. A 119-item QFFQ was developed including seven bread items, five soups or stews, 24 meat- or fish-based dishes, eight rice or pasta dishes, nine fruits and 14 vegetables. Frequency of consumption was assessed by eight categories ranging from ‘Never or less than one time in one month’ to ‘two or more times a day’.

Conclusion

We were able to highlight foods for intervention to improve dietary intake based on the major sources of energy, fat and sugar and the low consumption of fruit and vegetable items. The QFFQ is being used to evaluate a diet and lifestyle intervention in First Nations in north-western Ontario.

Reducing diabetes risk in American Indian women

BACKGROUND

American Indians experience high rates of type 2 diabetes. The impact of low-intensity interventions on diabetes risk among young American Indian women is unknown.

DESIGN

Randomized controlled trial.

SETTING/PARTICIPANTS

Community-based; participants were 200 young urban American Indian women who were block-randomized on fasting blood glucose (FBG) into intervention and control groups. Inclusion criteria included self-reported identity, aged 18-40 years, not pregnant, willingness to stay in urban area for 2 years, and not having type 2 diabetes. Measures were taken at baseline, 6, 12, and 18 months. Data were gathered in 2002-2006 and analyzed in 2006-2007.

INTERVENTION

Five discussion group sessions (one meeting per month for 5 months) were held focusing on healthful eating, physical activity, goal-setting, and social support.

MAIN OUTCOME MEASURES

Primary outcomes included dietary fat and vegetable consumption and self-reported physical activity. Secondary outcomes included cardiorespiratory fitness, insulin sensitivity, blood pressure, lipid profiles, percent body fat, BMI, intake of fruit, total sugar and sweetened beverages, FBG, and television viewing.

RESULTS

Mean vegetable and fruit intake increased significantly more in the intervention group than in the control group over time (group by visit interaction, p=0.02 and p=0.002, respectively). Both groups had significant increases in percent body fat and decreases in waist circumference, insulin sensitivity, blood cholesterol, LDL, television viewing, and total intakes of energy, saturated fat, sugar, and sweetened beverages.

CONCLUSIONS

A culturally influenced, low-intensity lifestyle intervention can improve self-reported intakes of vegetables and fruit over 18 months in young, urban American Indian women.

Dietary intake and a food-frequency instrument to evaluate a nutrition intervention for the Apache in Arizona

OBJECTIVE

To demonstrate how dietary data collected from 24-hour dietary recalls were incorporated into the development of a quantitative food-frequency questionnaire (QFFQ) for the Apache in Arizona.

DESIGN

A cross-sectional study was first conducted using 24-hour dietary recalls to identify foods for inclusion on a QFFQ that would be used to evaluate a nutrition intervention.

SETTING

The White Mountain and San Carlos Apache reservations in East-central Arizona.

SUBJECTS

The 24-hour dietary recalls were collected from a random sample of 53 adults (34 women and 19 men).

RESULTS

A QFFQ was developed that included all foods reported by two or more respondents, plus traditional and seasonal foods. Portion size was assessed using familiar household units and culturally appropriate food models. The final instrument contains 155 foods. Frequency of consumption is assessed using eight categories ranking from 'never or less than once a month' to '2 or more times a day'. Nutrient intakes and the five major food sources of energy, fat and sugar are presented.

CONCLUSION

The QFFQ developed is complete and up-to-date for assessing usual food and nutrient intake for the Apache in Arizona. The instrument will be used to evaluate a food store-based nutrition intervention to reduce risk of chronic diseases.

Canadian Aboriginal women have a higher prevalence of vitamin D deficiency than non-Aboriginal women despite similar dietary vitamin D intakes

Canadian Aboriginal women have high rates of bone fractures, which is possibly due to low dietary intake of minerals or vitamin D. This study was undertaken to estimate dietary intake of calcium and vitamin D by designing a culturally appropriate dietary survey instrument and to determine whether disparities exist between Aboriginal and white women. After validation of a FFQ, 183 urban-dwelling and 26 rural-dwelling Aboriginal women and 146 urban white women completed the validated FFQ and had serum 25-hydroxyvitamin D [25(OH)D] measured. Urban Aboriginal women had lower (P=0.0004) intakes of total dietary calcium than urban white women; there was no difference in rural Aboriginal women. Only a minority of all women met the adequate intake (AI) for calcium intake. Ethnicity did not affect total vitamin D intake; however, rural Aboriginal women consumed all of their dietary vitamin D from food sources, which was more (P<0.03) than both urban Aboriginal and white women. Rural and urban Aboriginal women had lower (P<0.0004) serum 25(OH)D than urban white women. We found that 32% of rural Aboriginal, 30.4% of urban Aboriginal, and 18.6% of urban white women were vitamin D deficient, with serum 25(OH)D concentrations<37.5 nmol/L. The high prevalence of vitamin D deficiency among Aboriginal women, combined with lower dietary intake of calcium, especially in older women, likely contributes to the higher incidence of fracture in this population.

Fish intake and serum fatty acid profiles from freshwater fish

BACKGROUND

Although high mercury concentrations in fish diets raise an alarm, fish can also be a healthy choice because it is the primary source of n-3 fatty acids (FAs). However, little information is available on the contribution of freshwater fish to serum FA concentrations.

OBJECTIVE

This study examined the FA pathway from fish to serum in 243 moderate consumers of freshwater fish.

DESIGN

A food-frequency questionnaire was used to determine the intakes of freshwater fish caught locally and not sold in markets and of fish purchased in markets (x +/- SD: 58 +/- 63 g/d). Locally caught freshwater fish accounted for an average of 45% of total fish intake. Fish were categorized as lean or fatty on the basis of the eicosapentaenoic acid + docosahexaenoic acid content estimated from published data. Serum FA concentrations were determined by gas chromatography.

RESULTS

The results showed no relation between total fish intake or estimated n-3 FA intake from all fish and serum n-3 FA concentrations. Only fatty fish intake, particularly salmonid, and estimated EPA + DHA intake from fatty fish were significantly associated with serum EPA + DHA (R2 = 0.41 and 0.40, respectively). No relation was observed between the quantity of locally caught fish (g/d) consumed or the estimated FA intake from locally caught fish and serum n-3 FAs. Age, sex, and lipid metabolism medication were associated with serum n-3 FA concentrations. Neither blood selenium nor blood mercury was associated with serum FAs.

CONCLUSION

The relation between fatty fish consumption and serum n-3 FAs cannot be generalized to all fish intakes.

The nutrition transition in American Indians

The purpose of this article was to examine whether a nutritional transition has occurred among American Indians (AI) by evaluating related articles and government health statistics. Findings indicate that although the primary health risk for the AI population around 1970 was undernutrition, now there is an obesity epidemic among all age groups that is associated with a loss of traditional food practices and reduced physical activity. Deaths caused by cardiovascular disease, diabetes mellitus, and cancer have outpaced death from infectious disease. With abundant high-energy foods and limited physical activity, the acculturated environment has resulted in obesity and increased mortality from chronic diseases. To improve AI health and survival, the obesity epidemic must be approached in a concerted, culturally appropriate manner with encouragement of traditional foods and safe opportunities for physical activity.

Mercury exposure in two coastal communities of the Bay of Fundy, Canada

There is a rising global concern with regard to mercury (Hg) exposure among coastal populations. Two communities on the Bay of Fundy (New Brunswick, Canada) were assessed by hair monitoring and dietary methods. Average concentration of total Hg in hair was 0.70+/-0.55 mg/kg (N=91) at Grand Manan and 0.42+/-0.15 mg/kg (N=52) at St. Andrews/St. Stephen. Average daily consumption of fresh fish and shellfish was 50+/-40 g/day for Grand Manan and 19+/-19 g/day for St. Andrews/St. Stephen. Average daily total Hg intake estimated from the food frequency and 24-h recall questionnaires was 0.05+/-0.04 microg Hg/kg bw/day at Grand Manan and 0.03+/-0.04 microg Hg/kg bw/day at St. Andrews/St. Stephen. A significant correlation (r=0.47, P=0.002) between Hg intake and hair was observed for Grand Manan. Low Hg intakes and body burden can be attributed to the low Hg levels found in the species commonly consumed: haddock, canned tuna, lobster, and pollock (all below 0.2 microg/g wet weight). The results showed that Hg exposure in these Canadian coastal communities is low; fish with higher levels of Hg (shark, tuna, swordfish, pickerel, and bass) are not consumed locally.

Impact of core and secondary foods on nutritional composition of diets in Native-American women

OBJECTIVE

To identify the core and secondary foods among Native-American women in Oklahoma and to determine their impact on nutrient and Food Guide Pyramid serving intakes.

DESIGN

This descriptive study explored food intakes from 4-day weighed food records. Nutrient intakes were estimated using reference data used in national survey data.

SUBJECTS/SETTING

Seventy-one Native-American women receiving services from three tribal health clinics in northeast Oklahoma. Statistical analyses performed A food-use frequency score was computed using frequencies of individuals consuming foods across each of 4 days of records. Leading contributors of nutrients and Food Guide Pyramid servings were identified from core and secondary foods.

RESULTS

Thirty foods comprised the list of core foods, led by soda, coffee, and white bread. A majority of total energy, fat, saturated fat, monounsaturated fatty acids, polyunsaturated fatty acids, cholesterol, carbohydrate, calcium, vitamin C, folate, discretionary fat, and added sugar were derived cumulatively from the core and secondary foods. Forty percent of fruit Food Guide Pyramid servings were accounted for by two core foods, bananas, and orange juice. More than half of meat and vegetable Food Guide Pyramid servings were derived from core and secondary foods.

CONCLUSIONS

Food patterning data are helpful in the development of effective nutrition education programs. We identified less nutrient-dense core foods that are contributing to discretionary fat and added sugar intakes. Targeted nutrition education programs for Native Americans should promote the nutrient-dense core and secondary foods, such as whole-wheat bread and fruit, while providing more healthful food alternatives to less nutrient-dense foods.

Serum folate and homocysteine levels in obese females with non-alcoholic fatty liver

OBJECTIVE

Folate depletion and hyperhomocysteinemia increase the risk for hepatic alcoholic damage and promote oxidative stress in animals. In addition, some investigators have reported an inverse association between serum folate and body mass index and a positive correlation between total homocysteine and fat mass. We investigated whether there is an association between serum folate and total homocysteine concentrations with the presence of non-alcoholic fatty liver disease (NAFLD) in obese subjects.

METHODS

Forty-three obese (body mass index > or =35 kg/m2) patients who underwent bariatric surgery and hepatic biopsy were included. Serum total homocyteine, folate and vitamin B12 concentrations and hepatic enzymes were measured. Liver biopsies were graded for the presence of fat, inflammation, and fibrosis on a scale from 0 to 3. A total histologic score was calculated based on the sum of partial scores. Severe NAFLD was defined as a total score of at least 4 or severe steatosis (partial score for fat = 3).

RESULTS

Severe NAFLD was present in 17 patients. Serum folate concentration was significantly lower in obese patients with NAFLD than in those with normal liver or minimal alterations (9.3 +/- 3.5 versus 12.2 +/- 3.1 ng/mL, P = 0.005). Serum total homocysteine and vitamin B12 concentrations were similar in both groups. An inverse correlation between serum folate concentration and body mass index was observed (r = -0.31, P = 0.046).

CONCLUSIONS

In this study, severe NAFLD in obese subjects was associated with lower serum folate concentrations and serum homocysteine and vitamin B12 concentrations were not associated with liver damage in obese subjects.

Lifestyles, diets, and Native American exposure factors related to possible lead exposures and toxicity

Lead exposure is still a national concern, and it is possible that Native Americans who live on reservations and pursue traditional lifestyles may be at higher risk through both their unique exposure profiles and their potentially greater sensitivity. A major component of the exposure assessment is the diet. For tribal members, traditional lifestyles that include native foods, medicines, and traditional practices have evolved and proven to be the most healthful over many thousands of years of coexistence with the environment. However, a completely traditional diet may not be fully available for a variety of reasons; so, one must also consider the adverse health consequences caused by the loss of healthy native foods and medicines, the contamination of remaining native foods, the inability to practice one's religion, and the possibly lower quality of the substitute diet. Health evaluations of lead exposure on reservations should therefore consider at least two types of diets in addition to the typical suburban diet: (a) traditional diets composed of native foods and medicines that would result in increased exposure if the plants and animals are contaminated and (b) disadvantaged or commodity food diets that result in widespread vitamin and mineral deficits of the sort known to increase absorption of and response to lead. Additional exposure to lead might come from reservation housing which is often older, although the prevalence of lead-based paint on reservations is unknown. The degree of physiological response could also be affected by widespread exposures to other neurotoxins (such as mercury and PCBs in fish), underlying disease patterns, and genetics. Although each of these factors is plausible, their prevalence singly or in combination is unknown. Any correlation between these risk factors and blood lead levels on reservations is also unknown. This paper begins to address these gaps by discussing the range of traditional and current diets that may exist among tribes and methods for developing a whole-lifestyle exposure scenario that is appropriate for an individual tribe. Some of the factors discussed in this paper may not apply to the large population of Native Americans who live in urban situations.