Phytates are compounds found in many plant foods, especially in beans and whole grains. Although phytates are linked with health benefits, they can also block the absorption of non-heme iron (the type of iron found in beans and other plant sources). To see how eating these phytate-rich foods affects nutrition status, scientists in Iowa assigned 28 non-anemic young women to either a high phytate (lots of whole grains, beans, nuts, and tofu) or low phytate (refined grains, eggs, and cheese, avoiding high phytate foods) diet for eight weeks, then tested their iron levels. After consuming a high phytate diet for 8 weeks, there was a 41% increase in serum iron response (measured by area under the curve). This indicates that “habitual consumption of [a high phytate] diet can reduce the negative effect of phytate on non-heme iron absorption among young women with sub-optimal iron stores.”
Journal of Nutrition. 2015 Aug;145(8):1735-9. (Armah SM et al.)

Palmitic acid (found in palm oil, shortening, butter, and red meat) is a type of saturated fat prevalent in the Western diet, while oleic acid (found in olive oil) is a type of monounsaturated fat prevalent in the Mediterranean diet. In a small study, researchers at the University of Vermont fed 16 adults either a diet high in palmitic acid or a diet high in oleic acid and low in palmitic acid to see how food choices affect the inflammatory response of various cells. All adults spent 3 weeks in each diet group, serving as their own control.  Although insulin sensitivity was not affected in this experiment, the scientists found that changing the diet to include more oleic acid and less palmitic acid was able to lower activation of certain cell signaling proteins (including TLR4 and NLRP3) that are associated with inflammation, oxidation and poor insulin signaling. These results suggest that shifting from a Western diet to a Mediterranean style diet (with greater proportions of oleic acid) may help fight inflammation.
Journal of Nutritional Biochemistry. 2015 Aug 1. pii: S0955-2863(15)00178-3. (Kien CL et al.)

Whole grains (like rye, oats, and whole wheat) have a strong history in traditional Scandinavian cuisine, but as in other regions, the food landscape is changing and refined grains have replaced some traditional foods. To see how eating whole grains relates to mortality, researchers analyzed the diets of over 120,000 people in Denmark, Norway, and Sweden.  The scientists found that those who ate the most whole grains had significantly lower risk of death from all causes. When analyzing individual whole grains, the researchers found significantly lower mortality rates in those who ate the most whole grain breakfast cereals, whole grain bread, oats, rye (only statistically significant for men), and whole wheat. These findings support existing evidence that whole grains may contribute to longevity.
British Journal of Nutrition. 2015 July 23:1-16. (Johnsen NF et al.) [Epub ahead of print]

In a small Italian study, researchers assigned 25 healthy adults to a Mediterranean meal (pasta, chicken breast, salad, bread, and an apple) prepared either with or without olive oil, then measured their cholesterol and blood sugar. After 30 days, the participants switched groups and ate the other meal, serving as their own control. The scientists found that 2 hours after eating, the meal without olive oil was associated with higher glucose and insulin levels, as well as higher “bad cholesterol” (LDL-C). In the second part of the experiment, the participants were assigned to a Mediterranean meal prepared with either olive oil or corn oil, switching groups after a 30 day washout period. Their blood sugar and cholesterol was tested after the meals as well. Two hours after eating, the meals with olive oil were associated with a lower increase in blood sugar and improved markers of blood sugar control (such as lower DPP, and higher GLP1 & GIP), as well as a smaller increase in “bad cholesterol” (LDL-C and oxidized LDL). These experiments indicate that meals with olive oil can help regulate blood sugar, and may help improve cholesterol.
Nutrition & Diabetes. 2015 July 20;5:e172. [Epub ahead of print.] (Violi F et al.)

Evidence is mounting that the healthiest diets are built around a variety of minimally processed, whole foods, and can’t be reduced to specific nutrients. To determine saturated fat’s role in heart disease risk, researchers from California reviewed the existing literature about saturated fats, polyunsaturated fats, carbohydrates, and heart disease. The scientists found that when saturated fat (found mostly in red meat and milk fat) is replaced with polyunsaturated fat (found mostly in nuts, seeds, and fish), heart disease risk decreases. However, when saturated fat is replaced with sugary refined carbohydrates, heart disease risk remains the same, if not worsens. The researchers also note a small, yet growing body of research that dairy fat (especially in fermented dairy, like yogurt), may be neutral (or even decrease risk) for heart disease. The researchers concluded that “overall dietary patterns emphasizing vegetables, fish, nuts, and whole versus processed grains form the basis of heart-healthy eating, and should supersede a focus on macronutrient composition.”
Annual Review of Nutrition. 2015 July 17;35:517-43. (Siri-Tarino PW et al.) [Epub]

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.)

Group activities (such as team building exercises) among co-workers can help improve employee performance, but new research suggests that even the simple act of breaking bread together can also have positive effects. To study how shared workplace meals affect job performance and cooperation, Cornell researchers surveyed 244 fire department officers, and visited 13 firehouses for in-person interviews. They found that cooking together and eating together were both significantly linked with better measures of work-group performance, and in some instances, better unit-level performance. There was no significant relationship between eating and cooking together and cooperative behavior, although better cooperative behavior was related to better work-group performance.
Human Performance. 2015 July 10;28(4):281-306. (Kniffin KM et al.)

While most whole grains are naturally gluten free (like quinoa, millet, and rice), many gluten-free packaged foods are made with refined, starchy flours, such as potato flour or white rice flour. To see how gluten free products stack up, researchers analyzed the nutrition on over 3200 food products in Australia, comparing the health of gluten free items to items containing gluten. Gluten free products were found to have significantly less protein across all major food groups, and gluten free pasta was found to be significantly less healthful than regular pasta (based on the Australian government’s “Health Star Rating”). Other than that, the researchers found no significant health differences between gluten free (GF) and gluten-containing products, concluding that “the consumption of GF products is unlikely to confer health benefits, unless there is clear evidence of gluten intolerance.”
British Journal of Nutrition. 2015 Jun 29:1-7. [Epub ahead of print]. (Wu JH et al.)

It seems that comfort foods like refined sweets might not be so comforting in the long run. Scientists in New York analyzed the eating patterns of nearly 70,000 women without depression across the U.S. , then tracked their health records over three years to see how diet relates to developing depression. The researchers found that both refined grains and added sugars were significantly tied to a higher risk of developing depression over the three year study, while fiber, vegetables, fruit (excluding juice), and lactose (a sugar found in milk) was linked with a significantly lower risk of depression. A higher intake of whole grains was also related to a lower risk of depression, although this relationship was not statistically significant. Overall, foods that contributed to a high glycemic index diet were associated with increased odds of developing depression. 
American Journal of Clinical Nutrition. 2015 Jun 24. [Epub ahead of print] (Gangwisch JE et al.)

Spicy foods are prominent in many traditional cultures throughout the world. To see if spicy food consumption is related to death risk, scientists asked over 487,000 Chinese adults about their spicy food intake, and then monitored their death rates over the next 7 years. Compared to those eating spicy foods (mostly chilli peppers) less than once per week, those eating spicy foods once or twice a week had a 10% lower risk of death from all causes, while those eating spicy foods 3-7 times per week had a 14% lower risk of death from all causes. Spicy foods were also linked with a lower risk of death from cancer, heart disease, and respiratory disease, specifically. This association might possibly be related to capsaicin, a beneficial compound in chilli peppers that has antioxidant properties.
British Medical Journal. 2015 August 4;351:h3942. (Lv J et al.) 

Given the prevalence of large portion sizes and high caloric meals at restaurants, cooking more meals at home may be a helpful strategy to eat healthier. In a study of more than 9,500 adults, researchers analyzed the relationship between the frequency of home-cooked dinners, and diet quality. Those who cooked dinner 6-7 days per week had a better diet quality than those who cooked dinner at home 0-1 nights per week, averaging 1g more fiber, 16g fewer sugars, 5g less fat, and 137 fewer calories per day. There was no significant relationship between home-cooked dinners and body weight. The researchers conclude that “if a person or someone in their household cooks dinner frequently, regardless of whether or not they are trying to lose weight, diet quality improves.”
Public Health Nutrition. 2015 Jun;18(8):1397-406. (Wolfson JA et al.)