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Lose Weight (and Fat) with a Vegetarian Diet

Vegetarians tend to weigh less than omnivores, but researchers wonder whether their body fat distribution might be different as well. To test this relationship, researchers randomly assigned 74 adults with type 2 diabetes to either a vegetarian or non-vegetarian diet for 6 months. Both diets were restricted by 500 calories per day, and the second half of the study included aerobic exercise for both groups. The vegetarian diet was almost twice as effective at weight loss (13.7 pounds lost) as the conventional calorie-restricted diet (pounds lost). The vegetarian diet also reduced subfascial fat (a type of internal fat related to poor blood sugar control) by 0.82 cm squared, but the conventional weight-loss diet did not.
Journal of the American College of Nutrition. 2017 June 10;1-6. (Kahleova H et al.)

Plant-Based Diet Can Reduce Obesity Risk by 43%

Nearly every healthy diet around the world is centered on a foundation of colorful produce. To see how eating more plant foods relates to obesity risk, scientists analyzed the diets of 16,000 healthy (non-obese) adults in Spain. Those eating the most plant-based diets (high in fruits, vegetables, grains, nuts, olive oil, and pulses, and low in meat, dairy, seafood, and other animal products) had a 43% lower risk  of becoming obese throughout the 10-year study than those with the most animal-based diets, even after controlling for age, physical activity, and other demographic factors. (Note that findings presented at meetings are typically viewed as preliminary until they’ve been published in a peer-reviewed journal.)
Presented at the European Congress on Obesity. Porto, Portugal. May 18, 2017. (Sanz J et al.)

Whole Foods Plant-Based Diet Can Improve Weight

Plant-based diets, which focus on fruits, vegetables, grains, and pulses, can be a great tool for eating healthy. In a small study in New Zealand, researchers randomly assigned overweight and obese adults to either a whole foods plant-based diet (with vitamin B12 supplementation) or a control group with no special diet for six months. Although the plant-based diet was not calorie restricted, those in the diet group lost on average 24 pounds after one year, and after excluding dropouts (49 of the 65 participants completed the study), the diet group also significantly improved their cholesterol.
Nutrition & Diabetes. 2017 Mar 20;7(3):e256. (Wright N et al.)

Some Neanderthals (Relatives of Early Humans) were Vegetarian

Despite heavy marketing of the Paleo diet and lifestyle, very little is known about what our early human ancestors actually ate. To learn more about their diets, scientists in Australia studied the DNA of dental plaque from the teeth of Neanderthals (relatives of early humans) who went extinct about 40,000 years ago. While there was evidence of a meat-based diet (including wooly rhinoceros and sheep) in what is today Belgium, the Neanderthal diet in what is today Spain indicated a vegetarian diet, including mushrooms pine nuts, and moss.
Nature. 2017 Mar 8. [Epub ahead of print] (Weyrich LS et al.)

Eating More Soy Linked with Less Breast Cancer Death

Soy foods (like tofu, edamame, or soy milk) have a complicated relationship with breast cancer, since soy has estrogen-like properties. To see if eating isoflavones (the major estrogen-like compound in soy) relates to breast cancer outcomes, researchers analyzed the eating habits and health outcomes of more than 6,000 newly-diagnosed breast cancer patients (all women) in the US, Canada, and Australia. Scientists found that women eating the most isoflavones (the amount in at least ¼ cup soymilk per day) were less likely to die over the 9-year study period, but the results were only statistically significant in women with hormone-receptor-negative breast cancers (the breast cancers unlikely to respond to hormonal therapy).
Cancer. 2017 Mar 6. [Epub ahead of print] (Zhang FF et al.)

Legumes Linked with Heart Health

Legumes, the food group that includes beans, peas, lentils, and peanuts, are central to traditional diets around the world. To see how legumes relate to heart health, scientists reviewed 14 studies with 367,000 participants in both Mediterranean and non-Mediterranean populations. They found that a high intake of legumes (roughly less than one serving per day, or three to four servings per week) was associated with a 6% lower risk of any heart disease, and a 10% lower risk of coronary heart disease specifically. However, no association was found between legume consumption and stroke risk.
Journal of Public Health Nutrition. 2017 Feb;20(2):245-254. (Marventano S et al.)

Strength & Cardiorespiratory Fitness of Vegetarian Athletes as Good, or Better, than Omnivores

More and more professional athletes are embracing plant-based diets, and for a good reason.  To see how diet relates to athletic abilities scientists analyzed the strength and oxygen uptake of 27 vegetarian athletes and 43 omnivorous athletes. They found that while there was no significant difference in strength (measured by torque) between vegetarian and non-vegetarian athletes, female vegetarian athletes had better oxygen uptake (measure by VO2 max) than their non-vegetarian counterparts (no significant difference for males). The authors conclude that “following a vegetarian diet may adequately support strength and cardiorespiratory fitness development, and may even be advantageous for supporting cardiorespiratory fitness.”
Nutrients. 2016 Nov 15;8(11). pii: E726. (Lynch HM et al.) 

Pulses Can be More Filling than Meat

Plant-based diets are shown to be more sustainable, but nutrition researchers want to know if they are as satiating as meat-centric meals. In a randomized, double-blind study, 43 healthy young men were given a patty made from either veal and pork (high protein), fava beans and split peas (high protein), or fava beans and potatoes (low protein). The participants rotated through each of the 3 meals (with a 2-week washout in between each one), serving as their own controls. Although the fava and split pea patty was rated as less palatable than the other two meals, it proved to be the most satiating, with participants reporting less hunger and appetite afterwards, and participants didn’t need to eat as much at the following meal to feel full. While both the fava/pea patty and veal/pork patty were both high protein, the additional fiber in the fava/pea patty could also have contributed to the fullness.
Food and Nutrition Research. 2016 Oct 19;60:32634. (Kristensen MD et al.)

Healthy Plant Foods (Whole Grains, Pulses, Vegetables, Nuts, etc.) May Lower Diabetes Risk

Plant-based diets are linked with numerous health benefits, but you must take care to choose healthier plant foods close to nature, that haven’t been refined or include lots of added sugars. To investigate the importance of this point, Harvard researchers analyzed the eating habits of 195,727  adults across three large cohorts, and tracked their health records for decades. Eating a healthy plant based diet (with whole grains, fruits, vegetables, nuts, legumes, vegetable oils, tea, and coffee) was linked with a 34% lower risk of type 2 diabetes, while eating a less healthy plant based diet (with fruit juice, sugary drinks, refined grains, potatoes, and desserts) was linked with a 16% higher risk of diabetes.
PLoS Medicine. 2016 Jun 14;13(6):e1002039. (Satija A et al.)

Plant-Based Diets Linked with Lower Risk of Type 2 Diabetes

Plant-based diets show promise for a number of . Using more than 20 years of health and nutrition data, researchers scored the diets of more than 200,000 U.S. adults to see how closely they aligned with a plant based diet (mostly plant foods, minimal animal foods), a healthy plant based diet (emphasizing whole grains, fruits, vegetables, nuts, and legumes), or an unhealthy plant based diet (emphasizing refined grains, juice, and sweets). Plant-based diets were associated with a 20% lower risk of type 2 diabetes, while healthy plant based diets indicated an even greater risk reduction (34%). On the other hand, unhealthy plant based diets were linked with a 16% increased risk of type 2 diabetes. The researchers note that “plant-based diets need not completely exclude animal foods,” as those with the highest healthy plant based diet scores averaged 4 servings of animal foods per day, compared to 5-6 servings per day in those with the lowest scores. 
PLoS Medicine. 2016 Jun 14;13(6):e1002039. (Satija A et al.)

Plant Based Diets Can Better Feed a Growing Population, without Deforestation

Forests are an important harbor of biodiversity and carbon storage, so cutting into forests to create more cropland could be very harmful to the ecosystem. To see how we can feed a growing world without cutting into forests, Austrian researchers analyzed 500 different scenarios with varying levels of cropland expansion, dietary patterns, and crop yields.  They found that “a large range of options exist to feed a no-deforestation world,” by 2050, but greatly varied based on what types of foods we’d choose to eat. For example, their models found that if the current North American diet (lots of meat and highly processed foods) continues to expand globally, only 15% of the scenarios involving this eating pattern are feasible. However, “all vegan scenarios and 94% of the vegetarian scenarios are feasible,” indicating the overall sustainability of plant based diets.
Nature Communication. 2016 Apr 19;7:11382. (Erb KH et al.)

Pulses May Help Aid Weight Loss

Dietary changes are a key target in obesity prevention programs, so many foods are being studied for their affect on body weight. To see if eating more pulses (the food group that includes beans, peas, lentils, and chickpeas) might help reduce obesity, researchers analyzed 21 randomized control trials looking at pulses’ role in weight, body fat, and waist circumference in overweight and obese adults. Diets that included dietary pulses did not significantly reduce waist circumference. There was a trend in reduction of body fat (-0.34%), but it was not significant as well. Overall, the researchers found that those eating about 1 serving of pulses per day lost, on average, about 0.75 pounds over six weeks. Not surprisingly, results were stronger in weight loss diets (3.8 pounds over 6 weeks) than weight maintenance diets (0.6 pounds over 6 weeks). Although the weight loss was small, this study indicates that a modest serving of pulses may help produce weight loss, even without cutting calories.
The American Journal of Clinical Nutrition. 2016 Mar 30. [Epub Ahead of Print] (Kim SJ et al.)