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.)

Primary open-angle glaucoma is an eye disease that can lead to irreversible vision loss. Because there is currently no cure for this disease, scientists are very interested in preventive measures, including diet. In a study analyzing over 100,000 health professionals, Harvard researchers found that those eating 1.45 servings of green leafy vegetables per day had an 18% lower risk of developing primary open-angle glaucoma than those only eating 0.31 servings of leafy greens per day. Dietary nitrate (a nutrient found in green leafy vegetables), was also significantly related to a lower risk of primary open-angle glaucoma.
JAMA Opthalmology. 2016 Jan 14:1-11. (Kang JH et al.) [Epub ahead of print]

Spanish researchers randomly assigned 239 adults (half with metabolic syndrome, half without) to either a Mediterranean diet, or a low fat, high complex carbohydrate diet (with foods like pasta and cereals) for two years. They found that the Mediterranean diet was able to “restore potentially beneficial members of the gut microbiota,” in patients both with and without metabolic syndrome. The low fat, high complex carbohydrate diet did not result in as many positive changes in gut microbiota as the Mediterranean diet did, although some beneficial changes still occurred.
The Journal of Nutritional Biochemistry. 2016 Jan;27:27-31. (Haro C et al.)

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.)

Maintaining a healthy weight and optimal nutrition can be a struggle for patients with celiac disease, but nutritious diets can help. In a small Italian study, researchers assigned 39 celiac patients to a Mediterranean gluten-free diet. The scientists found that celiac patients following a gluten free diet based on the Mediterranean diet improved their nutritional status, without inducing overweight or obesity. In fact, two of the four malnourished celiac patients were able to reach a healthy BMI, without becoming overweight or obese.
European Journal of Clinical Nutrition. 2016 Jan;70(1):23-7. (Barone M et al.)

In a small study, Spanish researchers randomly assigned 20 obese men to either a Mediterranean diet, or a low fat, high complex carbohydrate diet (with foods like pasta and cereals) for a year. After a year on their respective diets, both groups saw increases in various gut microbes that are thought to be protective against type 2 diabetes (Roseburia and Parabacteroides  distasonis for Med diet, and Prevotella and Faecalibacterium prausnitzii for low fat, high complex carb diet). The Mediterranean diet group also increased their insulin sensitivity over the year, meaning that their bodies better respond to insulin.
The Journal of Clinical Endocrinology and Metabolism. 2016 Jan;101(1):233-42. (Haro C et al.)

To see how diet during pregnancy affects the risk of childhood obesity, researchers analyzed data from over 1,800 mother-child pairs. They found that children were less likely to have a high waist circumference (a measure of abdominal obesity) at age 4 if their mothers were most closely following a Mediterranean diet during pregnancy. However, the researchers found no significant relationship between the expectant mothers’ diet and the subsequent BMI of their children in early childhood.
Pediatric Obesity. 2016 Jan 13. (Fernandez-Barres S) [Epub ahead of print]

Healthy food choices can be an important way to help prevent gestational diabetes, a type of diabetes that occurs during pregnancy. To learn more about types of foods that might be helpful or harmful, Harvard researchers analyzed the diets and health outcomes of over 15,000 women. They found that replacing two servings per week of potatoes with whole grains lowered the risk of gestational diabetes by 12% (compared to 10% for replacing potatoes with legumes, and 9% for replacing potatoes with other vegetables).
British Medical Journal. 2016 Jan 12;h6898. (Bao W et al.)

While most nutrition studies focus on food and nutrients, traditions and culture can also be used to enrich wellness. To see how changing the menu at nursing homes to reflect more culturally tailored meals affects dementia patients, Norwegian researchers conducted in-depth interviews with family members and nurses of patients at six nursing homes, spanning three cultural groups: Sami (or Lapps), Norwegian, and Black South African. According to the researchers, “Familiar tastes and smells awoke pleasant memories in patients and boosted their sense of well-being, identity and belonging, even producing words in those who usually did not speak.” They concluded that “traditional food further improves patients’ appetite, nutritional intake and quality of life.”
Journal of Clinical Nursing. 2016 Jan 11. [Epub ahead of print] (Hanssen I et al.)

Obesity prevalence among U.S. immigrant children, particularly those from Mexico, is high, so researchers are trying to understand how diet plays a role. Pennsylvania researchers analyzed the diet quality of Mexican immigrant mothers and their children across multiple generations. They found that first generation American children were more likely to abandon their traditional Mexican diet for more American foods (like fast food and highly processed foods), significantly lowering the nutritional quality of their diet. This suggests that encouraging families to cook with traditional ingredients, and encouraging retailers and farms to offer these traditional ingredients, may be a good strategy to improve the health of immigrant populations.
Social Science & Medicine. 2015 Dec 21;150:212-220. (Dondero M et al.)

Researchers in Seattle created a Mexican Diet Score to assess how traditional Mexican diets are related to insulin resistance and inflammation. Higher Mexican Diet Scores indicate eating more traditional Mexican foods, such as corn tortillas, beans, soup, fruits, vegetables, whole grains, and Mexican cheese, and lower levels of added sugars, refined grains, and added fats. In a study of nearly 500 healthy, post-menopausal women of Mexican descent, the researchers found that those most closely following a traditional Mexican diet had 23% lower levels of hsCRP (a measure of inflammation), and 15% lower insulin levels (indicating healthy blood sugar regulation) than those not following a traditional Mexican diet. In the overweight and obese women, a low Mexican diet score was also linked with higher insulin resistance. The researchers concluded that “greater adherence to traditional Mexican diets… could be beneficial in reducing the risk of obesity-related systemic inflammation and insulin resistance for women of Mexican descent.”
The Journal of Nutrition. 2015 Dec;145(12):2732-40. (Santiago-Torres M et al.)

Whole grains are a classic centerpiece to the morning meal for many families, but students may especially benefit from this practice. Researchers collected data from nearly 700 elementary school students in Kansas (average age = 7.5) to see how eating breakfast relates to standardized test scores. They found that while breakfast eaters scored significantly higher in all test areas, what the students ate made a big difference. Greater servings of whole grains were significantly related to higher scores in reading comprehension and fluency and math, while fruit juice was significantly correlated with lower math and reading comprehension and fluency scores.  
Journal of the American College of Nutrition. 2015 Dec 23:1-8 [Epub ahead of print] (Ptomey LT et al.)