evidence-based blog of Filippo Dibari

Posts Tagged ‘USA’

Vegetarianism and cardiometabolic disease risk factors: Differences between South Asian and US adults

In Over-nutrition on August 11, 2018 at 7:31 am

Jaacks LM1, Kapoor D2, Singh K2, Narayan KM3, Ali MK3, Kadir MM4, Mohan V5, Tandon N6, Prabhakaran D2.

Nutrition. 2016 Sep;32(9):975-84. doi: 10.1016/j.nut.2016.02.011. Epub 2016 Mar 4.

(downlowad)

Abstract

OBJECTIVES:

Cardiometabolic diseases are increasing disproportionately in South Asia compared with other regions of the world despite high levels of vegetarianism. This unexpected discordance may be explained by differences in the healthfulness of vegetarianand non-vegetarian diets in South Asia compared with the United States. The aim of this study was to compare the food group intake of vegetarians with non-vegetarians in South Asia and the United States and to evaluate associations between vegetarianism and cardiometabolic disease risk factors (overweight/obesity, central obesity, diabetes, hypertension, high triacylglycerols, high low-density lipoprotein, low high-density lipoprotein, and high Framingham Heart Score).

METHODS:

Using cross-sectional data from adults (age 20-69 y) in South Asia (Centre for Cardiometabolic Risk Reduction in South-Asia [CARRS] 2010-2011; N = 15 665) and the United States (National Health and Nutrition Examination Survey 2003-2006; N = 2159), adherence to a vegetarian diet was assessed using food propensity questionnaires. Multivariable logistic regression was used to estimate odds ratios and predicted margins (e.g., adjusted prevalence of the outcomes).

RESULTS:

One-third (33%; n = 4968) of adults in the South Asian sample were vegetarian compared with only 2.4% (n = 59) in the US sample. Among South Asians, vegetarians more frequently ate dairy, legumes, vegetables, fruit, desserts, and fried foods than non-vegitarians (all P < 0.05). Among Americans, vegetarians more frequently ate legumes, fruit, and whole grains, and less frequently ate refined cereals, desserts, fried foods, fruit juice, and soft drinks than non-vegetarians (all P < 0.05). After adjustment for confounders (age, sex, education, tobacco, alcohol, and also city in CARRS), South Asian vegetarians were slightly less frequently overweight/obese compared with non-vegetarians: 49% (95% confidence interval [CI], 45%-53%) versus 53% (95% CI, 51%-56%), respectively; whereas US vegetarians were considerably less frequently overweight/obese compared with non-vegetarians: 48% (95% CI, 32%-63%) versus 68% (95% CI, 65%-70%), respectively. Furthermore, US vegetarians were less likely to exhibit central obesity than non-vegetarians: 62% (95% CI, 43%-78%) versus 78% (95% CI, 76%-80%), respectively.

CONCLUSIONS:

There is greater divergence between vegetarian and non-vegetarian diets in the United States than in South Asia, and US vegetarians have more consistently healthier food group intakes than South Asian vegetarians. Vegetarians in both populations have a lower probability of overweight/obesity compared with non-vegetarians. The strength of this association may be stronger for US vegetarian diets, which were also protective against central obesity.

Position of the American Dietetic Association: vegetarian diets

In Over-nutrition, Under-nutrition on August 11, 2018 at 7:12 am

Craig WJ1, Mangels AR; American Dietetic Association.

(download pdf)

Abstract

It is the position of the American Dietetic Association that appropriately planned vegetarian diets, including total vegetarian or vegan diets, are healthful, nutritionally adequate, and may provide health benefits in the prevention and treatment of certain diseases. Well-planned vegetarian diets are appropriate for individuals during all stages of the life cycle, including pregnancy, lactation, infancy, childhood, and adolescence, and for athletes. A vegetarian diet is defined as one that does not include meat (including fowl) or seafood, or products containing those foods.

This article reviews the current data related to key nutrients for vegetarians including protein, n-3 fatty acids, iron, zinc, iodine, calcium, and vitamins D and B-12. A vegetarian diet can meet current recommendations for all of these nutrients. In some cases, supplements or fortified foods can provide useful amounts of important nutrients. An evidence- based review showed that vegetarian diets can be nutritionally adequate in pregnancy and result in positive maternal and infant health outcomes.

The results of an evidence-based review showed that a vegetarian diet is associated with a lower risk of death from ischemic heart disease. Vegetarians also appear to have lower low-density lipoprotein cholesterol levels, lower blood pressure, and lower rates of hypertension and type 2 diabetes than nonvegetarians.

Furthermore, vegetarians tend to have a lower body mass index and lower overall cancer rates. Features of a vegetarian diet that may reduce risk of chronic disease include lower intakes of saturated fat and cholesterol and higher intakes of fruits, vegetables, whole grains, nuts, soy products, fiber, and phytochemicals.

The variability of dietary practices among vegetarians makes individual assessment of dietary adequacy essential. In addition to assessing dietary adequacy, food and nutrition professionals can also play key roles in educating vegetarians about sources of specific nutrients, food purchase and preparation, and dietary modifications to meet their needs.

Carrying capacity of U.S. agricultural land: Ten diet scenarios

In Over-nutrition, Under-nutrition on November 27, 2016 at 3:33 am

Peters CJ, Picardy J, Darrouzet-Nardi AF, Wilkins JL, Griffin TS, et al. 2016. Carrying capacity of U.S. agricultural land: Ten diet scenarios. Elem Sci Anth 4: 000116

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Abstract

Strategies for environmental sustainability and global food security must account for dietary change. Using a biophysical simulation model we calculated human carrying capacity under ten diet scenarios. The scenarios included two reference diets based on actual consumption and eight “Healthy Diet” scenarios that complied with nutritional recommendations but varied in the level of meat content. We considered the U.S. agricultural land base and accounted for losses, processing conversions, livestock feed needs, suitability of land for crops or grazing, and land productivity.

Annual per capita land requirements ranged from 0.13 to 1.08 ha person-1 year-1 across the ten diet scenarios. Carrying capacity varied from 402 to 807 million persons; 1.3 to 2.6 times the 2010 U.S. population.

Carrying capacity was generally higher for scenarios with less meat and highest for the lacto-vegetarian diet. However, the carrying capacity of the vegan diet was lower than two of the healthy omnivore diet scenarios.

Sensitivity analysis showed that carrying capacity estimates were highly influenced by starting assumptions about the proportion of cropland available for cultivated cropping.

Population level dietary change can contribute substantially to meeting future food needs, though ongoing agricultural research and sustainable management practices are still needed to assure sufficient production levels.

 

They starved so that others be better fed: remembering Ancel Keys and the Minnesota experiment.

In Under-nutrition on June 3, 2014 at 1:51 pm

by Kalm LM, Semba RD.

 J Nutr. 2005 Jun;135(6):1347-52

(download)

Capture

Abstract

During World War II, 36 conscientious objectors participated in a study of human starvation conducted by Ancel Keys and his colleagues at the University of Minnesota. The Minnesota Starvation Experiment, as it was later known, was a grueling study meant to gain insight into the physical and psychologic effects of semistarvation and the problem of refeeding civilians who had been starved during the war.

Capture

During the experiment, the participants were subjected to semistarvation in which most lost >25% of their weight, and many experienced anemia, fatigue, apathy, extreme weakness, irritability, neurological deficits, and lower extremity edema. In 2003-2004, 18 of the original 36 participants were still alive and were interviewed.

 

CaptureMany came from the Historic Peace Churches (Mennonite, Brethren, and Quaker), and all expressed strong convictions about nonviolence and wanting to make a meaningful contribution during the war. Despite ethical issues about subjecting healthy humans to starvation, the men interviewed were unanimous in saying that they would do it all over again, even after knowing the suffering that they had experienced.

After the experiment ended, many of the participants went on to rebuilding war-torn Europe, working in the ministries, diplomatic careers, and other activities related to nonviolence.

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