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Vegetarian Diets Linked with Weight Loss

To determine if vegetarian diets might be useful for weight loss, Harvard researchers analyzed results from 12 different clinical trials encompassing 1,151 people. Those assigned to vegetarian diets lost 4.5 pounds more compared to those assigned to a non-vegetarian control diet, regardless of whether or not calories were restricted. Participants assigned to vegan diets (excluding all animal products) lost more weight (5.6 pounds) than those assigned to lacto-ovo vegetarian diets (3.2 pounds). The diets ranged from 9 weeks to 74 weeks, with a median duration of 18 weeks. The scientists conclude that “Vegetarian diets appeared to have significant benefits on weight reduction compared to non-vegetarian diets.”
Journal of General Internal Medicine. 2016 Jan;31(1):109-16. (Huang RY et al.)

Vegan Diets Linked with Lower Risk of Prostate Cancer

Over a quarter of cancer cases in men are prostate cancer, so dietary strategies to prevent prostate cancer could benefit many. To study this relationship, scientists analyzed the diet and prostate cancer diagnoses in a group of over 26,000 men for nearly 8 years. They found that vegan diets (diets that exclude all animal products, including dairy and eggs) were linked with a 35% lower risk of prostate cancer than non-vegetarian diets that included meat, poultry, fish, dairy, and eggs. Other vegetarian diets (that include dairy and eggs) did not show a statistically significant protective effect.
American Journal of Clinical Nutrition. 2016 Jan;103(1):153-60. (Tantamango-Bartley Y et al.)

Mediterranean and Vegetarian Diets May Benefit Gut Microbiome

Eating a variety of healthy plant foods is one of the best ways to nurture our friendly gut bacteria, and new research suggests that Mediterranean and vegetarian diets may be useful models. Scientists analyzed the eating patterns and gut bacteria of 153 Italian adults. They found that those most closely following a Mediterranean diet or vegetarian/vegan diet had higher levels of short chain fecal acids, a compound associated with many health benefits. On the other hand, those not following a Mediterranean diet had higher levels of urinary trimethylamine oxide, a potential risk factor for heart disease. The researchers also noted that both vegetarian/vegans and those on a Mediterranean diet scored highly on the Healthy Food Diversity Index, meaning that these eating styles could be a useful blueprint for people wanting to incorporate a variety of nutritious foods into their diet.
Gut. 2015 Sept 28. [Epub ahead of print] (De Filippis F et al.)

Plant Based Diets with Olive Oil Cost Less than USDA MyPlate Diet

Traditional plant-centered diets (such as the Mediterranean diet) are based on affordable local specialties and garden vegetables. To see if traditional ways of getting healthy meals on the table stand up to modern food economics, researchers calculated the cost of a 7-day meal plan for an economical version of the USDA MyPlate guidelines, and compared it to that of a plant-based diet with olive oil. They found that choosing a plant-based diet, instead of the budget MyPlate diet, could save $746.46 per person per year, and provide vastly more servings of vegetables, fruits, and whole grains.
Journal of Hunger & Environmental Nutrition. 2015 Sept 23. [Epub ahead of print] (MM Flynna et al.)

Beans Just as Filling as Meat

Pulses, the food group that includes beans, peas, chickpeas, and lentils, are central to traditional cuisines around the world, and are an especially important source of nutrients in plant-based diets. In a small study, researchers at the University of Minnesota fed 28 adults either a bean-based “meatloaf” (17g protein, 12g fiber) or a beef-based meatloaf (26g protein, 3g fiber) to compare how beans and meat affect fullness. The two meals had equal calories, fat, and weight. One week later, the adults changed groups and were given the other meatloaf, serving as their own control. The scientists found no significant differences in appetite or food intake at the next meal between the two different meatloaves, suggesting that beans are just as satiating as beef, possibly due to their fiber and protein content. However, the bean group did experience moderate gas and bloating.
Journal of Food Science. 2015 Sep;80(9):2088-93. (Bonnema AL et al.)

Eating Fish May Prevent Depression

Fish is well known for its place in many of the healthiest diets around the world. To determine the link between eating fish and depression risk, Chinese scientists reviewed 26 studies of over 150,000 people. The researchers concluded that “high fish consumption can reduce the risk of depression.”  
Journal of Epidemiology and Community Health. 2015 Sep 10. pii: jech-2015-206278. [Epub ahead of print.] (Li Fu et al.)

Vegetarian Diets Linked with More Calorie Burning

Weight is thought to be managed largely by balancing calories eaten with calories burned, so researchers are studying why some people tend to burn calories more easily than others. In an Italian study, researchers recruited 52 adults (half vegetarian, half not) and matched each group by age, BMI, and gender. All of the vegetarians had been following their diet for at least 3 years. After adjusting for age, BMI, exercise, and other lifestyle factors, the scientists found that the vegetarians had a significantly higher resting energy expenditure, meaning that their bodies burned more calories at rest. Of the different dietary components studied, higher intake of vegetable fats (oils, nuts, seeds) were most closely associated with the significantly higher resting energy expenditure seen in vegetarians. 
Nutrients. 2015 Jul 17;7(7):5933-47. (Montalcini T et al.)


Soy is Just as Filling As Beef

Soy foods, such as tofu, have anchored traditional Asian diets for centuries. In a small study, researchers at the University of Missouri fed 21 adults either a beef based lunch or a soy based lunch for two different days in a week to compare how different protein sources affect fullness. The two meals were matched for calories, macronutrients (carbohydrates, protein, fat) and fiber, and were the same serving size. One to two weeks later, the adults changed groups and were given the other meals, serving as their own control. The scientists found no significant differences in appetite, satiety or food intake at the next meal between the beef based meal or the soy based meal. As communities begin to embrace sustainable food systems and shift red meat to a smaller portion of the plate, soy proteins, like tofu, may offer an attractive alternative.
Journal of Nutrition. 2015 May;145(5):1010-6. (Douglas SM et al.)

Plant-Based Diets May Reduce Colorectal Cancer Risk

Colorectal cancer is the leading cause of cancer mortality, so learning more about dietary prevention is an important area of research. Scientists at Loma Linda University in California analyzed food patterns and health data from over 77,000 adults for an average of 7 years. After controlling for demographic and lifestyle factors (including age, smoking, physical activity, and family history), the researchers found that those who ate vegetarian diets had an approximately 20% lower risk of colorectal cancer compared with nonvegetarians. Researchers also found that pesco-vegetarians in particular (vegetarians who eat fish) had a much lower risk of colorectal cancer. These results support other studies linking the Mediterranean diet (a plant-based diet that features fish) with a decreased risk for colorectal cancer.
JAMA Internal Medicine. 2015 March 9. [Epub ahead of print] (Orlich MJ et al.)

Plant-based Diets Improve Heart Disease Markers in Overweight Kids

Plant-based diets have proven effective at reducing heart disease markers in adults, but with a large proportion of overweight and obese children, experts wonder if dietary interventions are effective on kids as well. In a small study in the Midwestern US, twenty-eight overweight and obese children (average age = 15) and their parents were assigned to either a plant-based vegan (no animal products at all), no-added fat diet (with only moderate avocado and nuts) or an American Heart Association diet (high in fruits, vegetables, and whole grains, but also includes low fat dairy, some plant oils, lean meat and fish, and permits some refined grains) for four weeks. The plant-based group significantly improved nine different risk factors of heart disease (including improved blood pressure, cholesterol, and weight), while the American Heart Association Diet significantly improved four risk factors.
The Journal of Pediatrics. 2015 Feb 11. [Epub ahead of print] (Macknin M et al.)

Avocados Help Lower Cholesterol

Avocados are the perfect example of how delicious healthy eating can be! Researchers assigned 45 overweight and obese adults to one of three cholesterol lowering diets: a lower fat (24% calories from fat) diet, a moderate fat (34% calories from fat) diet with one avocado per day, and a moderate fat (34% calories from fat) diet with sunflower and canola oils. Those on the avocado diet lowered their “bad cholesterol” significantly more than those on the other diets. Additionally, the avocado group was the only group to significantly decrease LDL particle number (a risk factor for heart disease) and improve the ratio of LDL to HDL (the gap between “bad” and “good” cholesterol). 
Journal of the American Heart Association. 2015 Jan 7 (Wang L et al.).

Healthy Diet with Whole Grains, Fruits, Vegetables, and Dairy Contains Friendly Microbes

Microbes are important for our digestive health, and researchers still have much to learn about how different foods impact our gut microbiome. In this study, researchers cooked 3 days worth of food from 3 different diets (a typical American diet with lots of convenience foods; a USDA recommended healthy diet with whole grains, fruits, vegetables, dairy, and lean meats; and a vegan diet consisting only of plant foods) and then analyzed the microbes present in the foods. The USDA recommended healthy diet was shown to have the highest total microorganisms. However, it was also the only meal plan that included yogurt, a non-heat-treated fermented food well known for its probiotic content.
PeerJ. 2014 Dec 9;(2):e659. doi:10.7717/peerj.659 (Lang JM et al.)